AWT Spring 2022 Analyst

the ANALYST The Voice of the Water Treatment Industry

Volume 29 Number 2

1300 Piccard Drive, Suite LL 14 • Rockville, MD 20850

Spring 2022

How Changes in Water Management Programs Could Present New Opportunities for Water Treaters Innovations and Solutions Pioneering the Transition Toward More Sustainable Wastewater Treatment Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring?

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System Practical Tips for Troubleshooting Wastewater Pretreatment Systems Volume 29 Number 2 Spring 2022

Special Feature, pg.72 Published by

Cover The evaporation pond at Xcel Energy's Cherokee Station.

Photo courtesy of Xcel Energy/Burns & McDonnell.

Spring 2022

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Volume 29

Number 2

How Changes in Water Management Programs Could Present New Opportunities for Water Treaters Matt Freije, HC Info

Water Management Program (WMP) performance data and trends indicate changes may be needed in the strategy for reducing the risk of Legionella and other pathogens in building water systems, and that water treaters will be instrumental in the implementation of the improved strategies. Changes needed to improve the performance of WMPs will allow water treaters to expand their contribution to public health and grow their businesses.

14 Innovations and Solutions Pioneering the Transition Toward More Sustainable Wastewater Treatment Chandler Mancuso, CWT, Omya, Inc.

The wastewater treatment industry has a major opportunity to develop more environmentally friendly treatment approaches and to be an integral part of a circular economy. Innovations in treatment technologies are becoming increasingly tailored to achieving the energy-neutral and energy-reduction targets set by many wastewater facilities across the globe.

24 Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring?

Jeff Bates, IDEXX Laboratories

Water treaters have several choices when testing premise plumbing for bacteriological parameters. Among these choices is whether to test for all Legionella species or for the primary pathogenic bacterium, L. pneumophila. This choice mirrors an ongoing discussion in the scientific community: whether monitoring for L. pneumophila or Legionella species is more protective of public health. The answer to this question has practical implications for water treaters, including what tests they use and how they report results to their customers.

36 Areas to Consider When Designing a Near-ZLD Wastewater Treatment System

Paul T. Brandt, P.E., and Bryan D. Hansen, P.E., Burns & McDonnell; Jason Miller and Adam Kortan, Xcel Energy Xcel’s Cherokee Generating Station was recently given new discharge permit limits for chlorides, sulfates, total inorganic nitrogen, and other constituents for the plant’s common outfall. Meeting the new chloride and sulfate concentrations became the limiting factor for technology selection and compliance. A near-zero liquid discharge wastewater treatment system was determined to be the best compliance option.

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Calendar of Events

5

President’s Message

6

Message From the President-Elect

67 Industry Notes 69 Discovering AWT 72 Amplify AWT 75 CWT Spotlight 77 Making a Splash 79 Capital Eyes 80 Tales From the Waterside 83 Beyond Water 88 T.U.T.O.R. 95 Business Notes 96 Membership Benefits 98 Advertising Index

52 Practical Tips for Troubleshooting Wastewater Pretreatment Systems Amanda Meitz, Biosolutions, LLC

Water treatment professionals working at food or manufacturing facilities where they already provide water treatment or clean-in-place chemistries may become effective contributors to the wastewater pretreatment system. An important role for water treatment personnel can be in helping management understand that the pretreatment system is not only a cost center but potentially a (admittedly) small revenue source. Evaluating the influent and performance of the pretreatment system can assist in targeting specific production areas where investment in system improvements can be justified.

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the ANALYST Volume 29 Number 2

1300 Piccard Drive, Suite LL 14 Rockville, MD 20850 (301) 740-1421 • (301) 990-9771 (fax) www.awt.org

2022 AWT Board of Directors President

Matt Jensen, CWT

Calendar of Events Association Events 2022 Business Owners Meeting

Secretary

September 20, 2022 Pan Pacific Vancouver Hotel Vancouver, Canada

Treasurer

2022 Annual Convention & Exposition

President-Elect

Stephen C. Hallier, CWT Noah Baskin

September 21–24, 2022 Vancouver Convention Centre Vancouver, Canada

John D. Caloritis, CWT

Immediate Past President

Michael Bourgeois, CWT

Directors

Mark Coldren, CWT Tammy Faber, MBA Kyle Rossi, CWT Fred Shurtz

2023 Annual Convention & Exposition

Ex-Officio Supplier Representative

Pam Simmons

Past Presidents

Jack Altschuler John Baum, CWT R. Trace Blackmore, CWT, LEED AP Michael Bourgeois, CWT D.C. “Chuck” Brandvold, CWT Thomas Brandvold, CWT Brent W. Chettle, CWT Dennis Clayton Bernadette Combs, CWT, LEED AP Matt Copthorne, CWT James R. Datesh John E. Davies, CWT Jay Farmerie, CWT Gary Glenna Charles D. Hamrick Jr., CWT Joseph M. Hannigan Jr., CWT

Mark R. Juhl Brian Jutzi, CWT Bruce T. Ketrick Jr., CWT Bruce T. Ketrick Sr., CWT Ron Knestaut Robert D. Lee, CWT Mark T. Lewis, CWT Steven MacCarthy, CWT Anthony J. McNamara, CWT James Mulloy Alfred Nickels Scott W. Olson, CWT William E. Pearson II, CWT William C. Smith Marc Vermeulen, CWT David Wagenfuhr Casey Walton, B.Ch.E, CWT Larry A. Webb

Staff

Executive Director Heidi J. Zimmerman, CAE Deputy Executive Director Sara L. Wood, MBA, CAE Member Services Director Angela Pike Vice President, Meetings Grace L. Jan, CMP, CAE Meetings Coordinator Caroline Bentley Meetings Planner Tim Foley Exhibits and Sponsorship Manager Brandon Lawrence Senior Director, Creative Services/Marketing Jennifer Olivares Marketing Coordinator Mary Claire Gordon Managing Editor Lynne Agoston Director of Accounting Services Dawn Rosenfeld

October 4–7, 2023 Amway Grand Hotel and Grand Rapids Convention Center Grand Rapids, Michigan

Also, please note that the following AWT committees meet on a monthly basis. All times shown are Eastern Time. To become active in one of these committees, please contact us at (301) 740-1421.

Second Tuesday of each month, 11:00 am—Legislative/Regulatory Committee Second Tuesday of each month, 2:30 pm—Convention Committee Second Wednesday of each month, 11:00 am—Business Resources Committee Second Friday of each month, 10:00 am—Special Projects Subcommittee Second Friday of each month, 11:00 am—Cooling Subcommittee Second Friday of each month, 2:00 pm—Pretreatment Subcommittee Third Monday of each month, 9:00 am—Certification Committee Third Monday of each month, 3:30 pm—Young Professionals Task Force Third Tuesday of each month, 3:00 pm—Education Committee Third Friday of each month, 9:00 am—Boiler Subcommittee Third Friday of each month, 10:00 am—Technical Committee Quarterly (call for meeting dates), 11:00 am—Wastewater Subcommittee

Other Industry Events

AWWA, Annual Conference & Expo, June 12–15, 2022, San Antonio, Texas ASHRAE, Annual Conference, June 25–29, 2022, Toronto, Canada BOMA, International Conference and Expo, June 25–29, 2022, Nashville, Tennessee ASHE, Annual Convention & Expo, July 17–20, 2022, Boston, Massachusetts ACS, Fall National Meeting & Expo, August 21–25, 2022, Chicago, Illinois WEFTEC, Annual Exhibition and Conference, October 8–12, 2022, New Orleans, Louisiana IWC, Annual Conference, November 6–10, 2022, Orlando, Florida RETA, Annual Convention, November 7–10, 2022, Reno, Nevada

The Analyst Staff

Publisher, Heidi J. Zimmerman, CAE Managing Editor, Lynne Agoston Technical Editor Michael Henley, mdhenleywater@gmail.com, (303) 324-9507 Advertising Sales Manager Carol Nettles, carol@adboomadvertising.com

The Analyst is published quarterly as the official publication of the Association of Water Technologies. Copyright 2022 by the Association of Water Technologies. Materials may not be reproduced without written permission. Contents of the articles are the sole opinions of the author and do not necessarily express the policies and opinions of the publisher, editor or AWT. Authors are responsible for ensuring that the articles are properly released for classification and proprietary information. All advertising will be subject to publisher’s approval, and advertisers will agree to indemnify and relieve publisher of loss or claims resulting from advertising contents. Editorial material in the Analyst may be reproduced in whole or part with prior written permission. Request permission by writing to: Managing Editor, the Analyst, 1300 Piccard Drive, Suite LL 14, Rockville, MD 20850, USA. Annual subscription rate is $100 per year in the U.S. (4 issues).

Please add $25 for Canada and Mexico. International subscriptions are $200 in U.S. funds.

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the ANALYST Volume 29 Number 2

President’s Message

By Matt Jensen, CWT

CWT If you’re not already a CWT, now is the time to start on the path to becoming certified. The CWT designation is the water treatment industry's definitive standard. There is no other credential that gives you the professional credibility you deserve. Visit the AWT website at www. awt.org for more information.

I was fortunate to attend the recent AWT training seminar in Cleveland, Ohio. What a fantastic event! I was so excited to see the high attendance, the collaboration, and the many friends I’ve been fortunate to make through my years being involved with AWT. This year, AWT was pleased to offer our newest training program, ASSE 12080, which was very well received by its attendees. This course, which AWT will offer once per year, prepares you to sit for the ASSE certification exam. Passing the exam will result in becoming a certified Legionella Water Safety and Management Specialist.

AWT Bylaws and the Amplify Campaign Very soon you will receive the draft bylaws. As you know, AWT has been working to address the sustainability of the association through our Amplify campaign.

The culmination of this campaign and these discussions will be a bylaws vote later this year. As a reminder, the two current proposals are to change the cap on water treatment company members to 500 employees or fewer and to add an individual membership category.

The Fundamentals and Applications session is a must for anyone with six months to two years of experience.

The session is very interactive and brings the mechanical room into the classroom. It focuses on real-world examples that we have all faced and allows plenty of time for a question-and-answer period.

To ensure maximum participation in the bylaws vote, we will be live-streaming the annual membership meeting this year from Vancouver. Each water treatment company member is entitled to one vote. Our online system will allow electronic voting on the bylaws, so be sure to participate. Your vote matters!

The Water Treatment Training session is also incredible!

The amount of material they pack into just a few days is amazing. I’ve been in the industry for years and always walk away learning a few new things. I would like to thank all of AWT’s hardworking and dedicated volunteers who donate their time, knowledge, and expertise to these seminars. These programs would not be possible without them.

Thank you for the opportunity to serve. I can be reached at president@awt.org.

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Message From the President-Elect

By Steve Hallier, CWT

Registration is now open for the 2022 AWT Annual Convention & Exposition, September 21–24, 2022, in Vancouver, British Columbia, Canada! It’s shaping up to be a memorable event! As COVID travel requirements are changing frequently, please make sure to check the AWT website for the most up-to-date information.

Silent Auction I’m also looking forward to seeing our friends from Pure Water for the World, which is doing incredible work in Haiti and Honduras. Pure Water for the World was recently named a finalist for the 2022 Classy Awards, which recognizes today’s most innovative charitable organizations. And thanks to the generosity of AWT members, the truck we funded is on its way to Honduras!

AWT Business Owners Meeting The AWT Business Owners Meeting will again be held in conjunction with the Annual Convention & Exposition on September 20. Our theme this year is Thriving in Uncertainty. It is safe to say that most AWT leaders and owners feel like they are “striving” in uncertainty with so many external forces we must deal with, from supply chain issues to record high inflation to a challenging employment market. Often, we end up doing just enough to get by—we “strive.” Thriving is different than striving. It is effort spent in the execution of a strategy that is clear and inspiring, not just to owners and leaders but to the employees and prospective employees as well. During this meeting you will hear from panels of your peers on topics such as developing your leadership team, living your core values, the metrics you should be tracking, and how to measure true profitability. You won’t want to miss this meeting!

We will once again have a silent auction during the convention. You’ll be able to bid on items that you use at work every day, plus some fun and unique things too.

And you’ll do this all while raising money for a great cause. Be sure to sign up!

Convention ROI We know that going to the Annual Convention & Exposition is an investment—both in time and dollars.

There is an actual cost to travel, plus time away from the office. You may think to yourself that you’ll skip this year, but I would argue that you can’t afford to miss it! While I always learn a lot in the sessions and from walking the exhibit hall, I learn even more just by speaking with my colleagues in the industry. Plus, I always come back refreshed and re-engaged in our industry.

As we continue to plan the 2022 Annual Convention, I welcome your feedback. I can be reached at steve@wetsolutionsinc.com. Thank you for the opportunity, and I look forward to serving you!

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How Changes in Water Management Programs Could Present New Opportunities for Water Treaters Matt Freije, HC Info

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New opportunities for water treaters could be just around the corner. Water Management Program (WMP) performance data and trends indicate changes may be needed in the strategy for reducing the risk of Legionella and other pathogens in building water systems, and that water treaters will be instrumental in the implementation of the improved strategies.

Water treaters already have a leading role in ASHRAE Standard 188 (1) WMPs—setting up water management plans for facilities, collecting samples tested for Legionella or other pathogens, and providing remediation equipment and services. Changes needed to improve the performance of WMPs will allow water treaters to expand their contribution to public health and grow their businesses.

Keys to WMP Success in Reducing Risk

If the premise of ASHRAE Standard 188 is sound, then fully implementing a comprehensive WMP will reduce the risk of legionellosis. Many facilities claim to have a WMP, but how many of them are comprehensive and fully implemented?

Out of the total number of facilities that should have a WMP per the risk factors outlined in ASHRAE 188, the percentage that have developed a comprehensive WMP is unknown and difficult to determine based on a simple survey, in part because, if asked, some facilities would report having a comprehensive WMP—probably in good conscience, believing they do—when in fact they have policies rather than control measures, or control measures that are ineffective, inadequate, or nonspecific.

According to research funded by the Water Research Foundation (2), the percentage of facilities with comprehensive WMPs is likely very low. Only 50% of education and hospitality facility managers surveyed had heard of ASHRAE 188. Awareness was even lower among multifamily facility managers—less than 30% knew that domestic (potable) water systems have conditions favorable to Legionella growth or had even heard of water management plans.

Since the percentage of facilities that have comprehensive WMPs is unknown, we attempted to answer a different question, one for which we have data to study: Of the facilities that have comprehensive WMPs, what percentage are fully implementing them?

Control measures determine the degree of comprehensiveness and implementation. To reduce the risk of disease caused by Legionella and other pathogens in building water systems, steps must be taken to control growth and transmission factors such as temperature, chemistry, flow, and biofilm. Control measures are thus the most important element of WMPs. The purpose of all other WMP elements—flow diagrams, list of team members, risk/hazard analysis, verification procedures, and validation methods—is to support the development and implementation of effective control measures.

Data Analyzed to Determine WMP Implementation and Effectiveness

To determine the degree to which facilities that have comprehensive WMPs are implementing them, the following metrics were analyzed for WMPs that had been active in a cloud-based WMP software application A for at least 12 months as of June 16, 2021:

Control measures must be included for all water systems and devices that present a significant risk. Measures for those devices must be specific, effective, and implemented. Such a monitoring program is designed to show whether each control measure has been adequately implemented, while WMP validation indicates the effectiveness of all control measures for a given system.

Control Measure (CM) compliance, based on the percentage of CMs with “OK” (i.e., up-to-date) verification status. It is reasonable to assume the facilities had comprehensive CMs based on the software’s defaults, but a limitation of this study is that WMP teams could have deactivated some of the software’s default CMs that apply to their facilities, making their WMPs less than comprehensive.

Facility Compliance

Number of Legionella and other microbial tests.

Even if the premise of ASHRAE 188 is sound, the standard will never significantly reduce legionellosis unless a high percentage of facilities fully implement a comprehensive WMP.

Number of domestic water temperature and disinfectant tests.

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How Changes in Water Management Programs Could Present New Opportunities for Water Treaters

per site in the recent 12 months (Table B) indicates fewer than 10% of the properties were sampling more than twice yearly.

The above metrics were compared with domestic water Legionella positivity.

Control Measure Compliance

Only 19% of the 908 WMPs that qualified for the study had CM verification compliance of greater than (>) 80% (Table A). Since some facilities may not be using the software’s CM verification tool, the percentage was calculated also for facilities with CM compliance > 0%.

Even in the unlikely scenario that all facilities with 0% compliance were not using the cloud-based software’s verification tool, still only one-third of remaining group had CM verification compliance > 80%.

Table B: Domestic Water Legionella Test, Results Recorded in Recent 12 Months

% of All Sites**

% of Sites with CM OK% > 0

0

41.96%

N.A.

0.5–49%

26.43%

45.54%

50–79%

12.44%

21.44%

80–94%

9.69%

16.70%

95–100%

9.47%

16.32%

100.00%

100.00%

Legionella Tests in Recent 12 Months

Sites

Percentage of Sites

0

755

83%

1–9

31

3%

10–19

36

4%

20–39

36

4%

40+

50

6% 100%

Table A: Percentage of WMPs with “OK” CM Status CM Compliance %OK*

continued

Comparison of CM Data and Legionella Positivity

Facilities with higher CM compliance generally performed more tests for Legionella, other microbes, temperatures, and disinfectants than did facilities with lower CM compliance (Table C). In short, facilities that kept up with their control measures also performed more tests.

Notes: * As of the end of the study period, rather than the average over the life of the WMP. ** Excluding WMPs activated for less than 12 months.

Importantly, Table C also indicates facilities that implemented control measures and performed tests were likely to have lower Legionella positivity. Legionella positivity was not considered for the 0% CM compliance group because that group’s number of Legionella tests was too low to make a reliable comparison. For all other groups, the average domestic water Legionella positivity decreased with increasing CM compliance and generally with increasing numbers of temperature and disinfectant tests.

Domestic Water Legionella Tests

Only 264 sites (29%) had recorded Legionella test results for domestic (potable) water, and of those, only 153 sites (17%) had recorded results in the recent 12 months.

Since at least 10 samples are typically needed from domestic water systems, the number of results recorded

Table C: Comparison of CM Compliance With Number of Tests and Domestic Water Legionella Positivity in WMPs Active > 12 Months CM Compliance % OK*

Legionella**

Other Microbial**

Temperature**

Disinfectants**

Legionella % Positive in DW ***

0

0.81

0.14

1.44

2.98

NA

0.5–49%

5.62

2.21

8.18

12.05

24.03%

50–79%

7.21

1.54

33.99

7.95

21.40%

80–94%

17.36

7.82

26.77

32.50

16.88%

95–100%

33.16

23.67

51.53

33.84

14.98%

Notes: *As of the end of the study period, rather than the average over the life of the WMP. ** Average number of tests in recent 12 months. *** For the life of the WMP, excluding sites with fewer than six domestic water test results total.

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How Changes in Water Management Programs Could Present New Opportunities for Water Treaters

continued

Supplementing Legionella Testing

A limitation of this study is that some facilities may have performed tests for Legionella, other microbes, temperatures, or disinfectants without recording the results in the cloud-based WMP software, but that would not likely affect the trends shown in Table C.

Monitoring parameters that can be measured continuously, automatically, and inexpensively can fill in gaps left by the following limitations of Legionella testing: 1. Most facilities are unable or unwilling to devote the time and money needed to perform an adequate number of Legionella tests (Table B).

Implications of the Performance Data

The data outlined in Table C indicates that the premise of ASHRAE Standard 188 is sound—implementing comprehensive control measures can reduce domestic water Legionella positivity.

2. With current technologies and cost, Legionella testing cannot be performed automatically or frequently. Getting test results only once or twice a year, or even monthly, is not enough.

The reality is, however, that a very low percentage of facilities are fully implementing comprehensive WMPs, which is likely why reported cases of legionellosis have not decreased since ASHRAE Standard 188 was released. If WMPs were required by law in more states, or by insurance carriers for liability policies, a much higher percentage of facilities would develop WMPs. However, since enforcing full implementation of comprehensive control measures is not feasible, such requirements will not likely be enough to significantly reduce cases of waterborne illness caused by domestic water systems.

3. Legionella tests alert facilities of Legionella but not to factors that lead to its growth. If the sampling and laboratory analysis are performed properly, Legionella test results show the cumulative and combined effect of various factors, such as temperatures, disinfectant levels, flow, and biofilm, as well as system design.

Seeing the “bottom line” for various factors is important, but for effective prevention, facilities must frequently monitor key factors instead of waiting months between Legionella tests to find out the cumulative and combined effect of them. This aligns with ASHRAE 188 and CDC recommendations (3–5) to monitor Legionella growth factors.

What could really move the prevention needle is requiring WMPs and making them easier. Busy facility personnel—like all of us—are more likely to do what does not take much time, effort, money, or expertise.

4. Legionella tests do not alert facilities to conditions caused by incidents such as water main breaks or water pressure shock that, if not effectively managed, could result in pathogen growth or release.

Automation is the key to making WMPs easy but effective. Automated monitoring, alerts, reporting, documentation—and to some extent even remediation—will require less time by facility personnel and less help from outside experts. As technologies improve, an increasing number of the key WMP elements—control measures, monitoring, and remediation—will ideally become fully automated and continuous.

5. Few individuals have the expertise and objectivity to respond to Legionella findings with remediation that effectively reduces the bacteria without overspending, damaging equipment, or increasing another hazard.

Automated monitoring would make WMPs more protective. As someone who wants to lower their blood sugar levels will be more conscience of their eating habits if they test their levels daily, facilities need frequent test results to be motivated to implement control measures.

Seeing inadequate test results for temperatures, disinfectants, water age, or other parameters will make applicable control measures or corrective actions climb their priority list.

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The Next Steps

Water treaters will likely have a key role in the steps needed to make WMPs easier and more effective: Studies to correlate pathogens to parameters that can be measured continuously, automatically, and inexpensively. Much is known about the effect of temperatures and certain disinfectants on Legionella.

Studying relationships between various pathogens and additional parameters will provide opportunities the ANALYST Volume 29 Number 2

How Changes in Water Management Programs Could Present New Opportunities for Water Treaters

continued

Territorial Health Officials on a project funded by CDC grant CDCRFA-OT18-1802, https://astho.org/Programs/Environmental-Health/ Documents/Legionella-Communications-Factsheet/.

to gather more data points for a fuller picture. Data sharing and collaborative research can reduce the time needed to find such correlations.

3. CDC (2017). “Developing a Water Management Program to Reduce Legionella Growth & Spread in Buildings: A Practical Guide to Implementing Industry Standards,” Centers for Disease Control and Prevention, Atlanta, Georgia, https://www.cdc.gov/legionella/maintenance/wmp-toolkit.html.

Water-related artificial intelligence technologies and improved sensors to automate continuous monitoring of parameters.

4. CDC (2018). “Healthcare Facility Water Management Program Checklist,” Centers for Disease Control and Prevention, Atlanta, Georgia, https://www.cdc.gov/HAI/pdfs/Water-Management-Checklist-P.pdf.

5. CDC (2021). “Controlling Legionella in Potable Water Systems. Legionella Control Toolkit,” Centers for Disease Control and Prevention, Atlanta, Georgia, https://www.cdc.gov/legionella/downloads/Control-Toolkit-Potable-Water.pdf.

Implementation of Internet of Things (IoT) in smart domestic water system equipment to make automatic adjustments based on parameter readings.

Endnote

A LAMPS is a cloud-based WMP software application developed and provided by HC Info.

In the years to come, water treaters will still help facilities set up WMPs. The water treaters with knowledge about automation technologies will have a greater role, helping their customers make WMPs easier and more preventive.

References

1. ASHRAE (2021). “Standard 188: Legionellosis: Risk Management for Building Water Systems,” American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, Georgia.

2. ASDWA/ASTHO (2021). “Legionella Communications Factsheet: A Guide for Health Agency Staff,” Association of State Drinking Water Administrators in partnership with the Association of State and

Matt Freije is the founder and CEO of HC Info and the content director for LAMPS, its cloud-based software for water management programs. He is a Certified Water Specialist and an approved ASSE 12080 instructor. Mr. Freije has provided Legionella education and information since 1995.

He can be contacted at mfreije@hcinfo.com.

This article is based on a paper presented by the author at the 2021 AWT Annual Convention & Exposition, which was conducted September 22–25, 2021, in Providence, Rhode Island.

Ask for Legiolert and deliver more accurate Legionella results The Legiolert® Test is a more accurate culture test for Legionella pneumophila Spread plate methods are notoriously inaccurate, with up to tenfold variability in results for the same sample.1 Multiple peer-reviewed studies have confirmed that the Legiolert Test provides more accurate and consistent results.2–5

See the difference the Legiolert Test can make at idexx.com/legiolertdifference.

References

1. Lucas CE, Taylor TH Jr, Fields BS. Accuracy and precision of Legionella isolation by US laboratories in the ELITE program pilot study. Water Res. 2011;45(15):4428–4436. doi:10.1016/j.watres.2011.05.030 2. Petrisek R, Hall J. Evaluation of a most probable number method for the enumeration of Legionella pneumophila from North American potable and nonpotable water samples. J Water Health. 2018;16(1):25–33. doi:10.2166/wh.2017.118 3. Spies K, Pleischl S, Lange B, et al. Comparison of the Legiolert/Quanti-Tray MPN test for the enumeration of Legionella pneumophila from potable water samples with the German regulatory requirements methods ISO 11731-2 and ISO 11731. Int J Hyg Environ Health.

2018;221(7):1047–1053.doi:10.1016/j.ijheh.2018.07.006 4. Sartory DP, Spies K, Lange B, Schneider S, Langer B. Evaluation of a most probable number method for the enumeration of Legionella pneumophila from potable and related water samples. Lett Appl Microbiol. 2017;64(4):271–275. doi:10.1111/lam.12719 5. Barrette I. Comparison of Legiolert and a conventional culture method for detection of Legionella pneumophila from cooling towers in Québec. J AOAC Int. 2019;102(4):1235–1240. doi:10.5740/jaoacint.18-0245

© 2021 IDEXX Laboratories, Inc. All rights reserved. • 2485785-01 • All ®/TM marks are owned by IDEXX Laboratories, Inc. or its affiliates in the United States and/or other countries. The IDEXX Privacy Policy is available at idexx.com.

2485785-01 AWT Summer 2021.indd 1

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Innovations and Solutions Pioneering the Transition Toward More Sustainable Wastewater Treatment Chandler Mancuso, CWT, Omya, Inc.

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Abstract

The responsibilities of wastewater treatment facilities are evolving beyond simply providing satisfactory effluent water quality. The wastewater treatment industry has a major opportunity to develop more environmentally friendly treatment approaches and to be an integral part of a circular economy. As this new approach to wastewater treatment gains traction, innovations in treatment technologies are becoming increasingly tailored to achieving the energy-neutral and energy-reduction targets set by many wastewater facilities across the globe.

The bulk of innovations supporting the transition to more sustainable wastewater treatment can be divided into three major categories: energy-efficient treatment technologies, energy recovery technologies, and digital solutions.

Emerging technologies such as the membrane-aerated biofilm reactor (MABR) and anaerobic membrane bioreactor (AnMBR) are allowing wastewater plants to achieve equal or better effluent water quality with lower energy consumption in comparison to traditional treatment practices. Anaerobic digestion, microbial fuel cells, and microalgae systems are all adaptions that can allow the wastewater plant to convert chemical energy in the system to usable electrical energy to power other treatment processes or sell to another consumer. Digital solutions personalized to the wastewater treatment market are allowing plants to get more accurate data faster, liberating personnel to better understand how the system is performing and what changes can be made to optimize the system’s performance. While all of these innovations come with their challenges, they are pioneering a more sustainable wastewater treatment industry and showcasing the changing drivers of the market.

Introduction

Historically, innovations in wastewater treatment were centered around the need for improved treatment performance because of evolving environmental regulations and emerging contaminants. While these are still drivers of innovation in several realms of the industry, the maturing concept of the water-energy nexus has shifted much of the focus to the energy consumption associated with wastewater treatment processes. Municipal wastewater treatment plants in the United States alone consume 30 terawatt hours of electricity annually, for

15

an annual total of $2 billion (1). This amount is higher than the annual electricity consumption of the entire country of Ireland, which the U.S. Energy Information Administration estimated to be 28 terawatt hours in 2019 (2). Additionally, electricity costs typically consume 25% to 40% of a wastewater utility’s operating budgets, depending on the size of the utility and the treatment plant design (3, 4).

In addition to the increasing energy costs to operate a wastewater treatment plant, the labeling of wastewater treatment plants as a contributor to global greenhouse gas emissions and the acceleration of the global environmental crisis has further intensified the urgency to improve energy efficiency in wastewater facilities. The U.S. Department of Energy has listed six strategic pillars to address the water-energy nexus, which includes the need to “optimize the energy efficiency of water management, treatment, distribution, and end use systems (5).”

In response to the strong initiative to improve the energy efficiency of wastewater treatment processes, the market is embracing the technological innovations that have been developed, and many plants around the country are setting “zero energy,” “energy neutral,” and energy reduction goals (6). Most of the energy reduction is being achieved through three major avenues: energy-efficient treatment technologies, energy recovery technologies, and digital solutions. The purpose of this article is to provide examples of advancements from each pathway listed and highlight the transforming mindset that wastewater treatment plants should be viewed more holistically as a resource asset and vehicle for protecting the environment.

Energy-Efficient Treatment Technologies

The activated sludge process has long been a dominant component of biological wastewater treatment. It is still largely an effective process for removing biodegradable organic pollutants as well as nutrients, especially when combined with more contemporary technologies, but the process is energy intensive. As shown in Figure 1, aeration is responsible for over half of the electricity required to run an activated sludge system (7). Therefore, technologies focused on reducing aeration requirements can translate into significant energy conservation for a treatment facility.

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continued

provide energy savings and expanded treatment capacity to plants with existing conventional infrastructure (10).

One technology gaining rapid traction, especially in developing wastewater markets, is the membrane aerated biofilm reactor (MABR). In the traditional activated sludge process, air is introduced into the water through diffusers or surface agitators to provide oxygen to the microorganisms suspended in the mixed liquor. In the MABR process, biofilm grows on a membrane, and oxygen is supplied directly to the microorganisms via diffusion through the membrane. This allows for a much more direct delivery of oxygen to the aerobic bacteria. The passive, direct supply of oxygen can reduce the energy use associated with aeration by 90%, according to a major manufacturer of MABR systems (8). Additionally, anoxic bacteria develop on the outside perimeter of the biofilm since the bulk water is absent of oxygen. This allows nitrification and denitrification to take place in the same tank, reducing the space requirement to achieve total nitrogen removal. The sessile bacteria also make the system more capable of tolerating variable wastewater compositions in comparison to the traditional activated sludge process where the microorganisms are suspended in the water column (9). Hybrid systems combining a conventional system with MABR technology are being studied as an opportunity to

Figure 1: Electricity requirements for activated sludge wastewater treatment.

Figure 2 (11) illustrates how MABR treatment technology works.

Figure 2: Depiction of MABR technology.

Source: Fluence Corp.

Another method for reducing the energy costs of aeration is to avoid it altogether and use anoxic and anaerobic treatment processes for contaminant removal. Anaerobic treatment has historically been depopularized due to the instability and temperature sensitivity of its operation, inefficiency treating wastes with low concentrations of organic contaminants, and generally lower effluent quality in comparison to aerobic systems (12). However, the considerably lower sludge production and absence of aeration make anaerobic treatment more intriguing to those with energy efficiency in mind.

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A technology that is accelerating the adoption of anaerobic treatment is AnMBR. The membrane separating the sludge from the treated effluent is the foundation of the MBR technology and the fulcrum to the acceptance of anaerobic treatment for more applications. It provides better effluent water quality than other anaerobic technologies and makes anaerobic treatment more suitable for low-strength wastewaters that contain modest levels of organic contamination, like municipal wastewater (13). Similar to an MABR, AnMBRs have demonstrated superior operational stability and resiliency compared to activated sludge treatment, making them better candidates for more extreme wastewaters (14). However, many applications still challenge the suitability of AnMBRs. Membrane fouling is a common nuisance with AnMBR systems, and the need to clean them frequently can increase energy and chemical costs (15). Gas recovery in anaerobic treatment systems, to be discussed in more detail later, is temperature sensitive, so plants in northern climates with low winter temperatures would have to heat their system to achieve optimal gas recovery, again increasing energy requirements (16). Nonetheless,

continued

continued advancements are making the operations of AnMBR systems more manageable under various treatment conditions, and more widespread use of anaerobic treatment technologies is expected in the coming years and decades.

While the cost of membranes is rapidly decreasing and the cost of energy is steadily increasing, the high cost of membranes may in some instances be financially prohibitive in adopting membrane-based technologies such as MABR and AnMBR (17). However, these cost trends are expected to continue, making membrane-based technologies increasingly more economical. Additionally, the costs to install and operate a treatment technology are highly system specific, including but not limited to the following: wastewater volume, wastewater matrix, local energy and material costs, target effluent requirements, and specific treatment design. Therefore, it is hard to generalize the relative costs of each treatment system.

Table A (9, 14, 15, 17) summarizes a high-level comparison of a traditional activated sludge design to innovative technologies such as MABR and AnMBR.

Table A: Comparison between conventional activated sludge and recently developed technologies: MABR and AnMBR Technology

Conventional Activated Sludge Treatment •

Advantages

•

• • Limitations

•

•

Key Applications

MABR

Anaerobic MBR

Very well studied and understood method of wastewater treatment Simple and lower-cost equipment

• •

Smaller space requirement Significantly reduced energy costs Simultaneous nitrification and denitrification Improved process resilience

•

Large space requirement Aeration and pumping are highly energy intensive Poor ability to cope with highly variable influent wastewater

•

High cost of membranes can drive up CAPEX and extend ROI Lack of familiarity with the systems due to its recent emergence

•

Centralized, low-strength, and consistent wastewaters, such as municipal wastewaters collected from large cities

•

Decentralized wastewater markets Geographies where energy costs are high Plants that need to add capacity with little available space Plants with a total nitrogen (N) limit

•

• •

•

• • •

• •

• • •

• •

Opportunity for energy reduction and recovery Significant sludge reduction over aerated technologies High process resiliency and effluent quality by anaerobic treatment standards Poor nutrient removal compared to aerated technologies Membrane fouling can be a challenge Temperature limitations High cost of membrane can drive up CAPEX and extend ROI High-strength wastes with good opportunities for biogas recovery Warm wastewaters and climates Plants with less stringent nutrient requirements

Notes: ROI = return on investment; CAPEX = capital expenditure Table sources: References 9, 14, 15, 17

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Energy Recovery Technologies

continued

Figure 3: Depiction of microbial fuel cell technology.

Source: Aquacycl

In addition to technologies that allow wastewater plants to reduce their energy demand, plants can also implement processes that capture and recover chemical energy from the process and transform it into usable energy as electricity or heat. Currently, the most common form of energy recovery in wastewater treatment facilities is anaerobic digestion (18). Anaerobic treatment, as previously mentioned, is already of interest due to reductions in sludge volume and energy demand when used as an alternative to aerobic processes.

Moreover, the biogas produced from the microorganisms during anaerobic digestion is 60 to 70% methane, which can be isolated and used to provide the plant with electricity and heat (19). Most plants implementing anaerobic processes send the sludge from the wastewater system to an anaerobic digester as a means of sludge management and biogas production, but biogas can also be recovered from other anaerobic processes within the treatment train if the methane yield is high enough. As mentioned in the previous section, there are operational barriers with the practical implementation of anaerobic digestion, but many municipal and industrial wastewater plants have successfully implemented it into their treatment regimens.

A concept that is recently being entertained as a practical, large-scale wastewater treatment technology is microbial fuel cells. The idea behind microbial fuel cells is that when some microorganisms break down pollutants in the wastewater, electrons are generated (20). When the electron-emitting microbes are in close proximity to an electrode, the electrical energy from the produced electrons can be collected and used (21). While the concept has been around for decades, only recent advances in research have allowed the technology to achieve commercial scale. While this technology is still in the very early stages of commercialization, modeling studies suggest that microbial fuel cells could be capable of providing energy-neutral wastewater treatment in instances of higher strength wastes, as the microbial activity required to degrade high concentrations of contaminants may produce enough electrical energy to satisfy the system’s own energy requirements (22). Figure 3 (23) illustrates the microbial fuel cell technology.

18

Systems fostering the use of algae in wastewater treatment have also recently entered the market as a developing solution to both the growing interest in resource and energy recovery as well as tightening nutrient discharge limitations. Algae are capable of working somewhat symbiotically with bacteria in wastewater systems. Bacteria produce carbon dioxide during cellular respiration, which algae use, along with the nutrients found in the wastewater stream, to grow.

Conversely, the photosynthetic algae can serve as an oxygen source for the bacteria. Since the algae serve as a source of oxygen, reliance on aeration for aerobic bacteria cultivation is reduced, cutting energy demand (24). Not only are algae known to be effective at removing nutrients and heavy metals from wastewaters, but the algae can also be harvested and used as a raw material source for biofuels or fertilizers (25). As with most emerging technologies, algae-based wastewater treatment technologies come with challenges, such as improving harvesting methods and better understanding the dynamics between the algae and bacteria present in the wastewater systems (26, 27).

Digital Solutions

While the water and wastewater industries have consistently lagged behind other industries in the adoption of digital solutions, there is a obvious trend of increased adoption of these technologies, and the expectation is that the trend will continue for years to come (28). There is a clear interest in using digital solutions to provide enhanced visibility into system operations and to uncover the ANALYST Volume 29 Number 2

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Innovations and Solutions Pioneering the Transition Toward More Sustainable Wastewater Treatment

continued

ways to reduce operating expenses, including energy usage. Digital solutions come with varying levels of sophistication, or layers, as outlined by the Smart Water Networks Forum (SWAN) (29). The levels are outlined here:

platform. This data centralization, combined with the data sorting and reporting tools often present in the software, makes it easier for system operators and managers to understand what changes are necessary to improve system operations.

1. Physical layer

Layer 5 is the most advanced layer and the home of truly powerful software solutions for the industry. These solutions take sensor data and use them to model system operations, predict future outcomes, or interpret what can be changed to enhance operational efficiency. In this layer lie technologies like “digital twins,” a virtual copy of a system created through the interpretation of data collected from the real system (32). This digital twin can be used to simulate future operation conditions, run theoretical scenarios, and learn what changes can be made to improve a specific function in the process.

2. Sensing and control layer 3. Collection and communication layer 4. Data management and display layer 5. Data fusion and analysis layer The physical layer is of course the data-less element that must exist in order for digital solutions to be warranted.

While sensing and control equipment have been used in the industry for decades, innovative solutions continue to improve the accuracy of the collected data as well as extend the breadth of parameters being monitored automatically and remotely. A notable example in the wastewater treatment industry is the proliferation of new technologies for microbial detection as alternatives to plate counts (30).

Cellular, Wi-Fi, and other common communication networks are frequently used in the wastewater industry to send data from sensors to data management and analysis software, but systematic digitization has induced an evolution of Layer 3 to produce networks that suit a variety of needs. For example, Low-Power-Wide-Area Networks (LPWANs) may be applicable to wastewater utilities looking to centralize comparably small amounts of data being retrieved from sensors that are geographically far apart (31).

Layer 4 has grown in abundance in recent years, with many companies offering software suites that allow for the integration of sensors collecting data on chemical concentrations and wastewater parameters into one

20

All of the layers, directly or indirectly, can help system operators and managers make the necessary changes and improvements to a treatment system to make it more effective and energy efficient. As the industry grows into the digital age, adversity will present itself in the forms of data security, inability to achieve universal adoption in the workforce, and difficulty in achieving compatible solutions to meet specific needs (33, 34).

Conclusion

In the wastewater treatment industry, the needs of the customer are trending beyond traditional selling points such as improved water quality, reduced chemical costs, reduced labor intensity, and exceptional technical support. While these benefits are still paramount, there is a growing realization that the wastewater treatment decision can also play an important role in energy conservation and environmental sustainability.

This reality is beginning to realign the priorities of the industry and drive the innovations entering the market.

As the industry navigates this paradigm shift, it is critical that suppliers continue to meet the needs of the market and evolve to assist treatment plant owners and operators in meeting these goals.

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7. Alkhafaji, A.; Alkhalidi, A.; Amano, R. ( June 2018). “Effect of Water Column Height on the Aeration Efficiency Using Pulsating Air Flow (Graph),” Jordan Journal of Mechanical and Industrial Engineering 12(1), pp. 45–50, https://www.researchgate.net/publication/327307908_Effect_ of_Water_Column_Height_on_the_Aeration_Efficiency_Using_Pulsating_Air_Flow.

References

1. Arzbaecher, C.; Parmenter, K.; Ehrhard, R.; Murphy, J. (2013).

“Electricity Use and Management in the Municipal Water Supply and Wastewater Industries,” Electric Power Research Institute, Palo Alto, California; Water Research Foundation, Denver, Colorado, https://www. waterrf.org/resource/electricity-use-and-management-municipal-water-supply-and-wastewater-industries.

8. Fluence (March 3, 2021). “What Is MABR?” Fluence Corp., White Plains, New York, https://www.fluencecorp.com/what-is-mabr/.

9. WaterWorld (Sept. 1, 2017). “The Rise of MABR Technology: Is the Future Bubbleless?” WaterWorld Wastewater, https://www.waterworld.com/ international/wastewater/article/16201158/the-rise-of-mabr-technologyis-the-future-bubbleless.

2. EIA (2019). “Electricity,” U.S. Energy Information Administration, https://www.eia.gov/international/data/world/electricity/electricity-consumption?pd=2&p=0000002&u=0&f=A&v=mapbubble&a=-&i=none&vo=value&t=C&g=0000000000000000000000000000 0000000000000000000001&l=249-ruvvvvvfvtvnvv1vrvvvvfvvvvvvfvvvou20evvvvvvvvvvnvvvs0008&s=31553280000 0&e=1546300800000&.

10. Lynch, J. (Feb. 23, 2021). “MABR Technology Could Optimize Wastewater Treatment, Say Researchers,” Treatment Plant Operator Magazine, https://www.tpomag.com/online_exclusives/2021/02/ mabr-technology-could-optimize-wastewater-treatment-say-researchers.

3. EPA (2013). “Energy Efficiency in Water and Wastewater Facilities: A Guide to Developing and Implementing Greenhouse Gas Reduction Programs,” U.S. Environmental Protection Agency, Washington, D.C., https://www.epa.gov/sites/production/files/2015-08/documents/ wastewater-guide.pdf.

11. Fluence ( July 22, 2021). “MABR Technology (Illustration),” Fluence Corp., White Plains, New York, https://www.fluencecorp.com/.

4. Gandiglio, M. et al. (October 2017). “Enhancing the Energy Efficiency of Wastewater Treatment Plants through Co-digestion and Fuel Cell Systems,” Frontiers in Environmental Science, https://www.frontiersin. org/articles/10.3389/fenvs.2017.00070/full#h5.

5. DOE ( July 2014). “The Water-Energy Nexus: Challenges and Opportunities,” U.S. Department of Energy, Washington, D.C., https://www. energy.gov/sites/default/files/2014/07/f17/Water%20Energy%20 Nexus%20Executive%20Summary%20July%202014.pdf.

12. Jimenez, J.A.; Bott, C.B. (2013). “Overview and Challenges of Anaerobic Wastewater Treatment: Is there a Place for it in Our Future?”, Proceedings of the Water Environment Federation, 2013(3), pp. 14–29, https://doi.org/1 0.2175/193864713813503080.

13. Wang, K.M.; Martin Garcia, N.; Soares, A.; Jefferson, B.; McAdam, E.J. (2018). “Comparison of Fouling between Aerobic and Anaerobic MBR Treating Municipal Wastewater,” H2Open Journal 1(2), pp. 131–159, https://doi.org/10.2166/h2oj.2018.109.

14. Dvorak, L.; Gomez, M.; Dolina, J.; Cernin, A. (Nov. 6, 2015) “Anaerobic Membrane Bioreactors—a Mini Review with Emphasis on Industrial Wastewater Treatment: Applications, Limitations and Perspectives,” Desalination and Water Treatment, https://www.tandfonline.com/doi/ citedby/10.1080/19443994.2015.1100879?scroll=top&needAccess=true.

6. Tarallo, S.; Shaw, A.; Zamenski, E.; et al. (2015). ”Demonstrated Energy Neutrality Leadership: A Study of Five Champions of Change,” Water Environment Research Foundation, Alexandria, Virginia, https://www. waterrf.org/system/files/resource/2019-07/ENER1C12b_0.pdf.

15. Velasco, P.; Jegatheesan, V.; Othman, M. (Dec. 17, 2018). “Recovery of Dissolved Methane from Anaerobic Membrane Bioreactor Using Degassing Membrane Contactors,” Frontiers in Environmental Science, https://www.frontiersin.org/articles/10.3389/fenvs.2018.00151/full.

16. Umble, A. (March 18-19, 2015). “Anaerobic MBR: Challenges and Opportunities,” symposium presentation, Hydrogen, Hydrocarbons and Bioproduct Precursors from Wastewaters, Washington, D.C.

Wastewater Treatment: DAF Innovation

17. Eoin, C.; Eoin, S.; Shanahan, J.; Semmens, M. (August 2008) “Comparative Economic Analysis of Full Scale MABR Configurations,” North American Membrane Research Conference, https://www.researchgate. net/publication/268806531_Title_Comparative_economic_analysis_of_ full_scale_MABR_configurations.

US Patents #8431022 & #9962631

The T²-Max® DAF Thickener handles high mixed solids flows without sacrificing separation performance.

18. EPA (accessed June 15, 2020). “Types of Anaerobic Digesters,” U.S. Environmental Protection Agency, Washington, D.C., https://www.epa. gov/anaerobic-digestion/types-anaerobic-digesters.

19. Vutai, V.; Lu, M.; Ma, X. (September 2016). “The Role of Anaerobic Digestion in Wastewater Management,” Journal of the Air & Waste Management Association, https://pubs.awma.org/flip/EM-Sept-2016/vutai. pdf.

20. Kundu, P.P.; Dutta, K. (2018). Progress and Recent Trends in Microbial Fuel Cells, Elsevier B.V., Amsterdam, the Netherlands, https://doi. org/10.1016/C2016-0-04695-8.

The HD²XLRator® DAF design encompasses the full array of newly advanced technological innovations.

21. Roy, S.; Marzorati, S.; Schievano, A.; Pant, D. (2017). “Microbial Fuel Cells,” Encyclopedia of Sustainable Technologies, pp. 245–259, https://www. sciencedirect.com/science/article/pii/B9780124095489101228.

22. Stoll, Z.; Dolfing, J.; Xu, P. (2018). ”Minimum Performance Requirements for Microbial Fuel Cells to Achieve Energy-Neutral Wastewater Treatment,” Water 10(3), p. 243, https://doi.org/10.3390/w10030243.

23. Aquacycl LLC. (2018). Aq-MFC [Illustration]. https://www.aquacycl. com/.

The Nx²JEM® DAF utilizes key hydraulic flow and laminar engineering principals to achieve high volume separation.

24. Arashiro, L. (Aug. 10, 2021). “Microalgae as a Sustainable Alternative for Wastewater Treatment,” International Water Association, London, England, https://iwa-network.org/microalgae-sustainable-alternative-wastewater-treatment/.

25. Abdel-Raouf, N.; Al-Homaidan, A.A.; Ibraheem, I. B.M. (2012).

“Microalgae and Wastewater Treatment,” Saudi Journal of Biological Sciences 19(3), pp. 257-275, https://www.sciencedirect.com/science/article/ pii/S1319562X12000332?via%3Dihub.

Contact PEWE at: 360-798-9268 www.pewe-usa.com

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26. Thompson, K. ( June 2021). “Trends and Developments in the Algae Wastewater Treatment Market,” GWI Water Data, Global Water Intelligence, Oxford, England, www.gwiwaterdata.com.

continued

Chandler Mancuso’s educational background includes a bachelor’s degree in environmental science and a master’s degree in chemistry, both from Oakland University in Rochester, Michigan. He has also earned his Certified Water Technologist and LEED Green Associate designations, and in 2020, he was selected for Water and Waste Digest’s 2020 Young Professionals Award. He is published in the industry journal Water Environment Research and has delivered technical presentations at several industry conferences. He now works for Omya Inc. and has more than five years of research and application experience in wastewater treatment, specializing in chemical treatment applications. Mr. Mancuso can be reached at chandler.mancuso@omya.com.

27. Higgins, B.T.; Gennity, I.; Fitzgerald, P.S.; Ceballos, S.J.; Fiehn, O.; VanderGheynst, J.S. (2018). “Algal-Bacterial Synergy in Treatment of Winery Wastewater,” npj Clean Water, 1, article no. 6, https://doi. org/10.1038/s41545-018-0005-y.

28. GWI ( June 2021). “Utility Market Forecast,” GWI Water Data. Global Water Intelligence, Oxford, England, www.gwiwaterdata.com.

29. SWAN (2021). “A Layered View of Smart Water Networks,” The Smart Water Networks Forum, Sussex, England, https://www.swan-forum.com/ swan-tools/a-layered-view/.

30. GWI ( June 2018). “Water Quality and Physical Parameters: The Rationale for Measurement,” GWI Water Data, Global Water Intelligence, Oxford, England, www.gwiwaterdata.com.

31. Nye, J. (March 16, 2017). “The Future of Water Management,” Water Online, https://www.wateronline.com/doc/the-future-of-water-management-0001.

32. WaterWorld (April 1, 2020). “Digital Twins for Managing Water Infrastructure,” WaterWorld Smart Water Utility, https://www. waterworld.com/water-utility-management/smart-water-utility/ article/14173219/digital-twins-for-managing-water-infrastructure.

33. Jiminez, M. (Aug. 7, 2018). “The Impact of Digitalisation on the Water Sector: An Interview with Rebekah Eggers,” International Water Association, London, England, https://iwa-network.org/the-real-impact-of-digitalisation-on-the-water-sector/.

This article is based on a paper presented by the author at the 2021 AWT Annual Convention & Exposition, which was conducted September 22–25, 2021, in Providence, Rhode Island.

34. Vesey, J.; Vairavamoorthy, K. ( January 2020). “Seizing the Digital Opportunity for Water,” Water Online, https://vertassets.blob.core. windows.net/download/e10f2c5c/e10f2c5c-a000-4b2b-a389-fb1c20f9b3a1/20_01_wol_digitalization_ebook.pdf.

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Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring?

Jeff Bates, IDEXX Laboratories

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Introduction

Association of Water Technologies (AWT) Position Statement and Guidance Document, “... Legionella testing is the only direct or “active” way (currently) to validate program effectiveness ...” (13).

Reducing Legionella risk is a key objective for the water treatment industry. Since the development of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 188 in 2015, many water treaters have realized they are in a unique position to work with building owners to minimize the risk of Legionnaires’ disease for building occupants. Both water treaters and the scientific community have become increasingly aware of the serious nature of this risk.

Water treaters have several choices when testing premise plumbing for bacteriological parameters. Among these choices is whether to test for all Legionella species or for the primary pathogenic bacterium, L. pneumophila. This choice mirrors an ongoing discussion in the scientific community: whether monitoring for L. pneumophila or Legionella species is more protective of public health.

The answer to this question has practical implications for water treaters, including what tests they use and how they report results to their customers. If the goal of Legionella sampling is to validate that a WPM is effectively reducing the risk of Legionnaires’ disease, it is important for water treaters to base their decisions on the most recent data and scientific consensus to ensure that goal is being met.

In the United States, Legionella pneumophila is the number one cause of reportable waterborne disease outbreaks, and the incidence of the disease increased six-fold from 2000 to 2018 (1). Despite our increasing understanding of the risk, experts have suggested that the number of cases of Legionnaires’ disease is 8 to 10 times higher than what is currently reported in the United States (2–6).

Expert Commentary

The risk posed by Legionella and Legionnaires’ disease is likely to increase moving forward. Legionella is an opportunistic pathogen, and individuals with lung damage are more likely to be susceptible. Increases in respiratory viral infections from the COVID-19 pandemic have drastically increased the number of individuals considered to be at risk for Legionnaires’ disease.

Outbreaks and new data continue to make headlines: a recent Morbidity and Mortality Weekly Report from the Centers for Disease Control and Prevention (CDC) revealed that all deaths resulting from treated recreational water outbreaks from 2015 to 2019 in the United States were due to Legionnaires’ disease, many of them hotel- or resort-related (7). In addition, outbreaks have recently been reported in Missouri, Indianapolis, and New Jersey, to name a few (8–10).

While the risk of Legionnaires’ disease is serious, the CDC indicates it is preventable with better water management. Water Management Programs (WMPs) reduce the risk of Legionnaires’ disease by minimizing the growth and transmission of Legionella in building water systems. While each water management plan should be unique to a specific building, experts recognize that every water management plan should be verified and validated, and that testing for Legionella is an effective way to perform validation (11, 12). As suggested by the 25

Recent research, scientific discussion, and regulatory bodies are increasingly aligning on L. pneumophila as the target of choice. As an example, the National Academies of Science, Engineering, and Medicine recently hosted a discussion of their consensus study on Legionella with a panel comprising members who served on the NASEM Committee on Management of Legionella in Water Systems (14). The panel agreed that targeting L. pneumophila for routine monitoring is supported by current science, highlighting that almost all clinical cases are associated with L. pneumophila, and that focusing monitoring on L. pneumophila can enable more frequent, cost-effective monitoring. A key conclusion of this discussion was that the scientific community clearly understands the serious risk to public health that L. pneumophila poses, whereas the public health benefit of controlling other Legionella species is less clear. The panel stressed that current science supports focusing on the pathogenic species, L. pneumophila, since it is critical to public health not to miss any L. pneumophila in building water systems.

ASHRAE adopts a similar stance in Guideline 12-2020: Managing the Risk of Legionellosis Associated with Building Water Systems (11). That document, which is used as a supplement to Standard 188, states: the ANALYST Volume 29 Number 2

Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

The disease causing potential of various other Legionella species, serogroups, and subtypes in all populations has not been established … Microbial testing that indicates a large presence of a Legionella strain with low disease-causing potential may represent little or no potential for disease in humans, while a smaller presence of a Legionella strain with established disease-causing potential, such as Legionella pneumophila serogroup 1, may represent a relatively higher potential for disease in humans.

Indeed, there is already precedent for focusing on the most pathogenic species in a genus despite the unknown virulence of other species. Walker and McDermott’s (15) recent publication in the Journal of AOAC International noted that Pseudomonas aeruginosa is the target of testing in hospitals, especially in the United Kingdom, even though other species of Pseudomonas may cause infections. Given this precedent, it is unclear why Legionella testing would follow a different model.

In a summary of Legionella control in France in the Annals of Infectious Disease and Epidemiology, Dr. Hartemann, former chair of the European Committee on Emerging and Newly Identified Health Risks, also advocates for an approach that targets L. pneumophila (16). After 10 years of monitoring for Legionella species, France amended its regulations to focus only on L. pneumophila, based on the limited number of cases of legionellosis linked to other species. The results of this decision will be discussed in more detail below, but one benefit cited was a “drastic decrease in unnecessary disinfections.”

specifies L. pneumophila as the pathogen of concern, not Legionella species.

L. pneumophila was also included in the third, fourth, and the draft of the fifth Contaminant Candidate List (CCL) from the EPA, which identifies chemical and microbial contaminants for potential future regulation under the Safe Drinking Water Act (SDWA) (18). In the draft of the fifth and most recent CCL, L. pneumophila was ranked as the second most dangerous microbial contaminant based on its ability to cause drinking water outbreaks, its occurrence in drinking water, and its potential health effects. L. pneumophila ranked higher than E. coli. The EPA also summarized its methodology for including various microbial contaminants in the drafted CCL document. Notably, the decision to include L. pneumophila was based on outbreak data from the CDC, which will be presented in more detail below. The EPA specifically lists L. pneumophila and not Legionella species, describing L. pneumophila as the “primary pathogenic bacterium.” At this time, it is unclear whether testing for Legionella will be federally required in the future, but the EPA has given a strong indication that any federal regulation would likely target L. pneumophila and not Legionella species.

The Causative Agent of Legionnaires’ Disease

Because the decision to monitor for L. pneumophila or Legionella species has important implications for water treaters, they should consider not just scientific commentary or review, but also examine data and reports on Legionnaires’ disease. The data present a clear picture of the risk of monitoring for all Legionella species versus L. pneumophila. Reviewing the data can effectively answer the question: “will monitoring only for L. pneumophila cause us to miss a significant amount of disease-causing Legionella?”

Beyond France, regulatory bodies in Canada and the United States recognize L. pneumophila as the proper target for Legionella risk mitigation. Quebec requires that cooling towers be routinely monitored for L. pneumophila, not Legionella species. While the United States does not yet have comprehensive Legionella regulations, the U.S. Environmental Protection Agency (EPA) has treatment techniques to address waterborne pathogens. Recently, the EPA has requested comments on whether L. pneumophila should be included in the fifth update of the Unregulated Contaminant Monitoring Rule (UCMR) and, in parallel, is considering updates to the Surface Water Treatment Rule that may include managing L. pneumophila (17). In both cases, the agency

In the United States, the CDC maintains data on outbreaks caused by Legionella between 1973 and 2019, including retrospective investigations into outbreaks that occurred prior to the 1976 American Legion convention outbreak at the Bellevue-Stratford Hotel in Philadelphia.

Of the 596 outbreaks recorded during that timeframe, only eight were reported to be associated exclusively with a known non-pneumophila species (19). Only seven hospitalizations and 11 deaths were associated 26

the ANALYST Volume 29 Number 2

Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

known to be an urgent and still unmet health risk that needs to be monitored and mitigated.

with non-pneumophila outbreaks, and the last identified non-pneumophila outbreak occurred in 2006. L. pneumophila, however, has been associated with at least 543 outbreaks over the same period. Those outbreaks caused over 1,700 hospitalizations and 371 deaths, which of course significantly undercounts the true toll of Legionnaires’ disease in the United States, as it does not consider sporadic and unreported cases. Statistically, L. pneumophila represents the true threat to public health, while the impact of non-pneumophila species is significantly less. Data from the Centers for Disease Control (CDC) show that other pathogens, like P. aeruginosa, pose a much more serious threat than non-pneumophila Legionella species (20).

Impact of Diagnostic Tests

It is important to consider these data in the context of minimizing risk in building water and cooling tower systems. Is testing systems for pathogens that have only caused eight outbreaks over the past 44 years, the last of which occurred 15 years ago, a valuable use of a water treater’s time and customers’ resources? A pragmatic approach to minimizing risk would focus efforts on the most significant threat.

The data from Europe paint a similar picture. The European Centre for Disease Control and Prevention (ECDC) monitors individual cases of Legionnaires’ disease in addition to outbreaks. The species of Legionella associated with each case is often confirmed by clinical culture. Only 2% of culture-confirmed cases reported from 2009 to 2015 were associated with a known non-pneumophila species (21). Importantly, 1% of these culture-confirmed cases were associated with Legionella longbeachae, which is primarily associated with potting soil, and is therefore not relevant to water-testing decisions. Therefore, less than 1.5% of culture-confirmed cases of Legionnaire’s disease in Europe were caused by non-pneumophila species that colonize water systems. In comparison, L. pneumophila caused 96% of culture-confirmed cases over the same period.

The implications of these data for water treaters are the same: L. pneumophila represents a serious threat to public health, while the true threat from non-pneumophila species is unknown and may be less serious than other non-Legionella waterborne pathogens. Said differently, the risk posed by Legionella species is an interesting question that merits further study, but L. pneumophila is 27

A common critique of data on Legionnaires’ disease is related to the method of diagnosis. The urinary antigen test (UAT) is a common method of diagnosis that only detects infections caused by L. pneumophila serogroup 1. It has been suggested that the use of this test skews the data towards L. pneumophila. However, a recent study by Julien Beauté and colleagues from the ECDC showed that only 45% of culture-confirmed cases in Europe were also ascertained by UAT. The study still found that 98% of those cases were caused by L. pneumophila (22). Denmark also provides an interesting case study: 80 to 90% of cases of Legionnaires’ disease are initially diagnosed by PCR, which detects cases caused by all Legionella species. However, the data on which species cause disease are the same. In 2020, 93% of cases diagnosed by PCR were found to be caused by L. pneumophila, and only two cases could be culture confirmed for a non-pneumophila species. (23) These figures account for the bias introduced by the UAT and reach the same conclusion—that L. pneumophila causes the overwhelming majority of disease.

The study by Beauté and colleagues also provides important data on the importance of L. pneumophila as a causative agent in different settings. Water treaters may question whether it is more important to monitor for non-pneumophila species in healthcare settings. The study illustrated that the proportion of cases caused by L. pneumophila is greater, and statistically equivalent, in healthcare-acquired cases as it is in community-acquired cases of Legionnaires’ disease (22). These data suggest that L. pneumophila is the appropriate target for water treaters in hospitals, nursing homes, and other general healthcare settings, in addition to hotels and other non-healthcare buildings.

The combined data support the emerging consensus that L. pneumophila is an appropriate target for risk mitigation efforts. Infections from non-pneumophila species represent a minimal portion of Legionnaires’ disease infections, and likely present a lower risk than other, non-Legionella pathogens. Water treaters can be confident that a validation testing strategy that targets L. pneumophila is aligned with the current data and science. the ANALYST Volume 29 Number 2

Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

These data also support the conclusion that non-pneumophila Legionella species are less virulent than L. pneumophila. The NASEM report on the Management of Legionella in Water Systems reviews several characteristics of L. pneumophila that may cause it to be more likely to cause disease in humans (1). This conclusion is further supported by empirical evidence. One study identified that non-pneumophila Legionella species made up 47% of isolates from cooling towers in the United States (24), but zero cooling tower outbreaks in the United States were attributable to species other than L. pneumophila (19).

Legionella regulation was first implemented in 1999.

As mentioned above, after 10 years of monitoring for all Legionella species, the legislation was amended to mandate testing only for L. pneumophila (16). In addition to avoiding unnecessary remediation, this approach has also been more successful than regulations that require testing and remediation for all Legionella species.

Germany and Italy both require testing for all Legionella species, and Legionnaires’ disease incidence increased 413% in Germany and 269% in Italy from 2009 to 2017 (Figure 1). Though France also reported an increased incidence, it was far less, at 147% (27, 28).

Experience From the Field

These data rebut the common argument that non-pneumophila Legionella species ought to serve as an indicator of the presence of L. pneumophila since the data show that focusing specifically on the pathogen of concern has in fact improved health outcomes. Monitoring should focus on the specific bacteria that present the highest risk to achieve the best outcomes for public health.

At the smallest scale, the city of Garland, Texas, implemented a regulation to test cooling towers in multifamily housing units for L. pneumophila in 2005 (25). Over the next 10 years, the number of cooling towers that tested positive declined steadily to zero. Due to the low number of annual cases and the fact that cases may originate from non-cooling tower sources, interpreting data by clinical cases is complicated. However, the fact that there were no reported cases of legionellosis in Garland in 2015, after several years of one to three reported cases, is a positive development. The data from Garland mirror the experience in Quebec, which also mandates that cooling towers be routinely tested for L. pneumophila.

Since the implementation of that regulation, the number of cooling towers with contamination above the action limits has dropped by 50% (26).

Regulations focusing on L. pneumophila may lead to better risk management and public health outcomes in several ways. When recommending focusing Legionella testing on L. pneumophila, the World Health Organization (WHO) suggested that “when a microbiological parameter is defined taxonomically, the parameter is much less prone to ambiguous results” (29). In practice, this means that focusing on L. pneumophila can eliminate unnecessary actions and uncertainty around how to react to a non-pneumophila positive result, and resources can be applied to mitigate the known health risk. It is also important to note that every disinfection comes with its own health risks, not to mention incremental damage to equipment. A strategy that minimizes unnecessary disinfection is therefore also important to public health. Focusing monitoring on L. pneumophila can both maximize public health benefits and eliminate the risks and costs associated with disinfections related to non-pneumophila Legionella species.

All these data support Legionella testing strategies that focus on L. pneumophila. Based on these and similar data, certain jurisdictions have decided to implement regulations that require testing only for L. pneumophila.

These regulations have been shown to be more successful than regulations that target all Legionella species.

The most prominent example of the impact of testing only for L. pneumophila comes from France, where

“The most prominent example of the impact of testing only for L. pneumophila comes from France, where Legionella regulation was first implemented in 1999.”

28

the ANALYST Volume 29 Number 2

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Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

Figure 1: Legionnaires’ disease incidence in France, Germany, and Italy, indexed to 2009.

The confluence of all these findings should make water treaters confident in adopting a testing strategy that targets L. pneumophila. This approach has been recommended in recent discussions with scientific experts and in peer-reviewed studies, the data show that Legionnaires’ disease from non-pneumophila Legionella species is a much less significant threat than disease from L. pneumophila and is likely even less significant than other waterborne pathogens, such as P. aeruginosa.

Testing specifically for L. pneumophila also has been demonstrated to be effective and successful in multiple geographies. Based on this evidence, the more appropriate question facing water treaters may be “when should Legionella testing include non-pneumophila species?”

Testing in Places Giving Immunosuppressive Therapy

Research has shown that patients undergoing immunosuppressive therapy are more likely to be at risk for non-pneumophila Legionella infections (30). This suggests that periodic or regular testing for non-pneumophila Legionella species in healthcare facility areas where this type of patient may be exposed to aerosols could be

beneficial. Examples would include areas where residential patients are receiving chemotherapy, or areas housing transplant patients. It is important to note that this type of monitoring does not need to extend to healthcare facilities that do not house patients receiving immunosuppressive therapy since more than 98% of nosocomial or healthcare-acquired Legionnaires’ disease is caused by L. pneumophila (22).

Methodological Considerations

For years, the only testing method available for Legionella was a traditional spread plate culture. This method recovers both L. pneumophila and some other Legionella species, so it has always been relatively simple to report results for all Legionella species detected. Recently, several new Legionella tests have been introduced. Many of these methods are not culture-based, and AWT suggests a culture-based test may be preferred for WMPs (13).

However, there is now a culture-based alternative to the traditional spread plate method. This method, a liquid culture method, has been compared to traditional spread plate methods in several peer-reviewed publications, most recently by researchers at the EPA (31–41).

“Focusing monitoring on L. pneumophila can both maximize public health benefits and eliminate the risks and costs associated with disinfections related to non-pneumophila Legionella species.”

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Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

“Many water treaters may be hesitant to change their existing practices, but this new choice facing water treaters requires them to rethink their testing in order to better protect their customers and their own reputations.”

Conclusions

All these studies found that liquid culture was at least as sensitive for L. pneumophila as traditional spread plate methods, and the majority (including EPA research by Boczek et al. (41)) found that liquid culture was more sensitive, meaning it is less likely to miss dangerous L. pneumophila amplifications than the traditional method.

This supports earlier research demonstrating that traditional spread plate methods are notoriously inaccurate (42). Notably, all the research on liquid culture has demonstrated it has very low false positive rates, well below what is generally considered acceptable for microbiological methods.

These findings change the calculus for water treaters.

Previously, water treaters could simply request data on all Legionella species “just to be safe.” Today, water treaters must decide between requesting a test that has been shown to be more likely to find L. pneumophila, if it exists in a water system, or a test that may miss L. pneumophila but may find other species. Based on the data, the choice should be clear—it is more important to find L. pneumophila, a known, dangerous pathogen, than to potentially find other Legionella species.

Many water treaters may be hesitant to change their existing practices, but this new choice facing water treaters requires them to rethink their testing in order to better protect their customers and their own reputations. Current practices are not working, as evidenced by the continuously rising rates of Legionnaires’ disease incidence. While rising rates are a result of many factors, and targeting L. pneumophila alone cannot be expected to reverse these trends, the data clearly show that it would be a positive change and contribute to better risk management.

32

Understanding that testing for L. pneumophila is recommended by experts, supported by clinical data, and is more effective in practice can have important implications for water treaters. Focusing on L. pneumophila also allows water treaters to do just that—focus. Water treaters reduce risk in hundreds or thousands of buildings, and time spent unnecessarily remediating one building for a non-pneumophila species might mean time not spent identifying and remediating a serious and life-threatening L. pneumophila amplification in another.

While it may seem harmless to simply collect information on another, related pathogen of uncertain risk, it is a dangerous allocation of resource away from an urgent threat to customers’ businesses. Missing growth of L. pneumophila creates serious risk; focusing resources on L. pneumophila specifically minimizes that risk.

It is critical for water treaters to align their programs and practices with the latest scientific thinking, data, and conclusions. The available literature and data demonstrate that L. pneumophila is the primary causative agent of Legionnaires’ disease, that the risk posed by non-pneumophila Legionella species is unknown and likely less significant than the threat from other waterborne pathogens, and that focusing testing on L. pneumophila leads to improved health outcomes, and therefore reduced risk for customers.

the ANALYST Volume 29 Number 2

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Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

References

1. National Academies of Sciences, Engineering, and Medicine (2020).

Management of Legionella in Water Systems, The National Academies Press, Washington, D.C., https://doi.org/10.17226/25474.

2. Dooling, K.L.; Toews, K.-A.; Hicks, L.A.; Garrison, L.E.; Bachaus, B.; Zansky, S., Carpenter, L. R., Schaffner, B., Parker, E., Petit, S., Thomas, A., Thomas, S., Mansmann, R., Morin, C., White, B., & Langley. G. E. (2015). Active bacterial core surveillance for legionellosis—United States, 2011–2013. Morbidity and Mortality Weekly Report, 64(42):1190-1193.

3. Mercante, J.W.; Winchell, J.M. (2015). “Current and Emerging Legionella Diagnostics for Laboratory and Outbreak Investigations,” Clinical Microbiology Reviews 28(1), pp. 95-133.

4. Phin, N.; Parry-Ford, F.; Harrison, T.; Stagg, H. R.; Zhang, N.; Kumar, K.; Lortholary, O.; Zumla, A.; Abubakar, I. (2014). “Epidemiology and Clinical Management of Legionnaires’ disease,” Lancet Infectious Diseases, 14:1011-1021.

5. St-Martin, G.; Uldum, S.; Mølbak, K. (2013). “Incidence and Prognostic Factors for Legionnaires’ disease in Denmark, 1993-2006,” ISRN Epidemiology, volume 2013, Article ID 847283, 8 pages.

6. von Baum, H.; Ewig, S.; Marre, R.; Suttorp, N.; Gonschior, S.; Welte, T.; Lück, C. (2008). “Community-Acquired Legionella pneumonia: New Insights from the German Competence Network for Community-Acquired Pneumonia,” Report for the Competence Network for Community Acquired Pneumonia Study Group, Clinical Infectious Diseases, 46, pp.

1356-1364.

7. Hlavsa, M.C.; Aluko, S.K.; Miller, A.D.; et al. (2021). “Outbreaks Associated with Treated Recreational Water—United States, 2015–2019,” Morbidity and Mortality Weekly Report, 70, pp. 733–738, http://dx.doi. org/10.15585/mmwr.mm7020a1.

8. Jones, K. (April 16, 2021). “Two Cases of Legionnaires' Disease Linked to Macon (Missouri) Hotel,” KOMU-8, Macon, Missouri, https://www. komu.com/news/midmissourinews/two-cases-of-legionnaires-diseaselinked-to-macon-hotel/article_ba67654e-9f07-11eb-aefb-d7ca60d407f5. html.

9. WTHR.com staff. (April 12, 2021). “Indianapolis Healthplex Closes after Some Members Get Legionnaires' disease,” WTHR, Indianapolis, Indiana, https://www.wthr.com/article/news/local/indianapolis-healthplex-closes-after-some-members-get-legionnaires-disease/531-28d1f2aaf4e9-4326-8f81-b98993a522a5.

10. Persichilli, J.M. (March 2, 2021). “NJ Department of Health Investigating Cluster of Legionnaires’ Disease Cases in Union County,” Press Release, New Jersey Department of Health, https://www.nj.gov/health/news/2021/ approved/20210302a.shtml (accessed June 1, 2021).

11. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (2020). “Guideline 12-2020— Managing the Risk of Legionellosis Associated with Building Water Systems, https://www. techstreet.com/ashrae/standards/guideline-12-2020-managing-the-risk-of-legionellosis-associated-with-building-water-systems?product_id=2111422#jumps.

17. EPA (March 11, 2021). “Revisions to the Unregulated Contaminant Monitoring Rule for Public Water Systems,” Public Meeting. Regulations. gov, https://www.regulations.gov/document/EPAHQ-OW-2020-0530-0001.

18. EPA ( July 19, 2021). “Drinking Water Contaminant Candidate List 5—Draft,” Regulations.gov, https://www.regulations.gov/document/ EPA-HQ-OW-2018-0594-0031.

19. 19.CDC ( July 9, 2021). “National Outbreak Reporting System,” Centers for Disease Control and Prevention, Atlanta, Georgia.

20. CDC (2019). “Antibiotic Resistance Threats in the United States,” Centers for Disease Control and Prevention, Atlanta, Georgia, http://dx. doi.org/10.15620/cdc:82532.

21. European Centre for Disease Prevention and Control (2011-2017).

“Surveillance Report: Legionnaires’ Disease in Europe (Years 2009– 2015),” European Centre for Disease Prevention and Control, Stockholm, Sweden, https://www.ecdc.europa.eu/en/legionnaires-disease/surveillance-and-disease-data/surveillance.

22. Beauté, J.; Plachouras, D.; Sandin, S.; Giesecke, J.; Sparén, P. (2020).

“Healthcare-Associated Legionnaires’ Disease, Europe, 2008−2017,” Emerging Infectious Diseases 26(10), pp. 2309–2318, https://doi. org/10.3201/eid2610.181889.

23. Statens Serum Institut (SSI). (2021). “No 18 – 2021,” EPI-NEWS, https://en.ssi.dk/news/epi-news/2021/no-18---2021.

24. Llewellyn, A.C.; Lucas, C.E.; Roberts, S.E.; Brown, E.W.; Nayak, B.S.; Raphael, B.H.; Winchell, J.M. (2017). “Distribution of Legionella and Bacterial Community Composition among Regionally Diverse U.S. Cooling Towers,” PLoS One, 12, https://doi.org/10.1371/journal. pone.0189937.

25. Whitney, E. A.; Blake, S.; Berkelman, R.L. (2017). “Implementation of a Legionella Ordinance for Multifamily Housing, Garland, Texas,” Journal of Public Health Management and Practice, 23(6), 601–607. https://doi. org/10.1097/PHH.0000000000000518.

26. Racine, P.; Smith, P.; Elliott, S. (Sept. 28, 2018). “Key Factors in Legionella Control and the Positive Impact of Regulations for Water Treatment Professionals,” paper presented at 2018 Annual AWT Convention, Tampa, Florida.

27. European Centre for Disease Prevention and Control (2017-2021).

“Surveillance Report: Annual Epidemiological Report for 2015-2019: Legionnaires’ Disease,” European Centre for Disease Prevention and Control, Stockholm, Sweden, https://www.ecdc.europa.eu/en/legionnaires-disease/surveillance-and-disease-data/surveillance.

28. European Centre for Disease Prevention and Control (2014). “Surveillance Report: Annual Epidemiological Report for 2012-2013: Respiratory Tract Infections,” European Centre for Disease Prevention and Control, Stockholm, Sweden, https://www.ecdc.europa.eu/en/legionnaires-disease/ surveillance-and-disease-data/surveillance.

29. WHO (2017). “Drinking Water Parameter Cooperation Project Support to the revision of Annex I Council Directive 98/83/EC on the Quality of Water Intended for Human Consumption (Drinking Water Directive) Recommendations,” World Health Organization Regional Office for Europe, Bonn, Germany, https://ec.europa.eu/environment/water/ water-drink/pdf/WHO_parameter_report.pdf.

12. CDC ( Jan. 11, 2021). “Toolkit for Controlling Legionella in Common Sources of Exposure,” Centers for Disease Control and Prevention, Atlanta, Georgia, https://www.cdc.gov/legionella/downloads/Control-Toolkit-All-Modules.pdf.

13. AWT (2019). “Legionella 2019: A Position Statement and Guidance Document,” Association of Water Technologies, Rockville, Maryland, https://www.awt.org/pub/?id=035C2942-03BE-3BFF-08C34C686FB7395C.

30. Muder, R.R.; Yu, L.V. (2002). “Infection Due to Legionella Species Other than L. pneumophila,” Clinical Infectious Diseases 35(8), pp. 990-998, https://doi.org/10.1086/342884.

14. NASEM (Dec. 10, 2020). “Management of Legionella in Water Systems— Follow Up Event,” National Academies of Sciences, Engineering, and Medicine, Washington, D.C., https://www.nationalacademies.org/ event/12-10-2020/management-of-legionella-in-water-systems-follow-up-event.

15. Walker, J.T.; McDermott, P.M. (2021). “Confirming the Presence of Legionella pneumophila in Your Water System: A Review of Current Legionella Testing Methods,” Journal of AOAC International, 1-13, https:// doi.org/10.1093/jaoacint/qsab003.

16. Hartemann, P. (2018). “Evolution of Legionella Control in France 1998–2018,” Annals of Infectious Disease and Epidemiology 3(3), p. 1035.

34

31. Sartory, D.; Spies, K.; Lange, B.; Schneider, S.; Langer, B. (2017).

“Evaluation of a Most Probable Number Method for the Enumeration of Legionella pneumophila from Potable and Related Water Samples,” Letters in Applied Microbiology, 64, pp. 271-275, https://doi.org/10.1111/ lam.12719.

32. Spies, K.; Pleischl, S.; Lange, B.; Langer, B.; Hübner, I.; Jurzik, L.; Luden, K.; Exner, M. (2018). “Comparison of the Legiolert™/Quanti-Tray® MPN Test for the Enumeration of Legionella pneumophila from Potable Water Samples with the German Regulatory Requirements Methods ISO 11731-2 and ISO 11731,” International Journal of Hygiene and Environmental Health 221(7), pp. 1047–1053, https://doi.org/10.1016/j. ijheh.2018.07.006.

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Is Testing for Legionella pneumophila or Legionella Species Better for Routine Monitoring? continued

33. Petrisek, R.: Hall, J. (2018). “Evaluation of a most Probable Number Method for the Enumeration of Legionella pneumophila from North American Potable and Nonpotable Water Samples,” Journal of Water and Health 16(1), pp. 25-33, https://doi.org/10.2166/wh.2017.118.

41. Boczek, L.A.; Tang, M.; Formal, C.; Lytle, D.; Ryu, H. (2021). Comparison of Two Culture Methods for the Enumeration of Legionella pneumophila from Potable Water Samples,” Journal of Water Health 19(3), pp. 468–477, https://doi.org/10.2166/wh.2021.051.

34. Rech, M.M.; Swalla, B.M.; Dobranic, J.K. (2018). “Evaluation of Legiolert for Quantification of Legionella pneumophila from Non-potable Water,” Current Microbiology, 75, pp. 1282-1289, accessible at https://doi. org/10.1007/s00284-018-1522-0.

35. Barrette, I. (2019). “Comparison of Legiolert and a Conventional Culture Method for Detection of Legionella pneumophila from Cooling Towers in Québec,”, Journal of AOAC International 102(4), pp. 1235-1240, accessible at https://doi.org/10.5740/jaoacint.18-0245.

36. Scaturro, M.; Buffoni, M.; Girolamo, A.; Cristino, S.; Girolamini, L..; Mazzotta, M.; Sabattini, M.A.; Zaccaro, C.; Chetti, L.; Laboratory, M.A.; Bella, A.; Rota, M.C.; Ricci, M.L. (2020). “Performance of Legiolert Test versus ISO 11731 to Confirm Legionella pneumophila Contamination in Potable Water Samples,” Pathogens, 9, accessible at https://doi. org/10.3390/pathogens9090690.

37. Inoue, H.; Baba, M.; Tayama, S. (2020). “Evaluation of Legiolert for Quantification of Legionella pneumophila from Bath Water Samples,” Biocontrol Science 25(3), pp. 179-182, https://doi.org/10.4265/bio.25.179.

38. Monteiro, S.N.; Robalo, A.M.; Santos, R.J. (2021). “Evaluation of Legiolert™ for the Detection of Legionella pneumophila and Comparison with Spread-Plate Culture and qPCR Methods,” Current Microbiology, 78, pp. 1792–1797. https://doi.org/10.1007/s00284-021-02436-6.

39. Checa, J.; Carbonell, I.; Manero, N.; Marti, I. (2021). “Comparative Study of Legiolert with ISO 11731-1998 Standard Method-Conclusions from a Public Health Laboratory,” Journal of Microbiological Methods, 186, https:// doi.org/10.1016/j.mimet.2021.106242.

42. Lucas, C. E.; Taylor, T.H., Jr.; Fields, B.S. (2011). “Accuracy and Precision of Legionella Isolation by U.S. Laboratories in the ELITE Program Pilot Study,” Water Research 45(15), pp. 4428–4436, https://doi.org/10.1016/j. watres.2011.05.030.

Jeff Bates is the strategic marketing manager for Premise Water at IDEXX. In his role, he is responsible for promoting testing for waterborne pathogens in premise plumbing systems globally and the IDEXX culture tests Legiolert and Pseudalert. He holds a bachelor’s degree in environmental studies from Middlebury College and received his MBA from the Darden School of Business at the University of Virginia. Mr. Bates can be contacted at Jeff-Bates@idexx.com.

This article is based on a paper presented by the author at the 2021 AWT Annual Convention & Exposition, which was conducted September 22–25, 2021, in Providence, Rhode Island.

40. McCuin, R.M.; Bartrand, T.A.; Clancy, J.L. (2021). “Legionella pneumophila Recovery Using Legiolert and a Traditional Culture Method. AWWA Water Science, e1228, https://doi.org/10.1002/aws2.1228.

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the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System Paul T. Brandt, P.E., and Bryan D. Hansen, P.E., Burns & McDonnell; Jason Miller and Adam Kortan, Xcel Energy

Abstract

Xcel’s Cherokee Generating Station was recently given new discharge permit limits for chlorides, sulfates, total inorganic nitrogen (TIN), and other constituents for the plant’s common outfall. Meeting the new chloride and sulfate concentrations became the limiting factor for technology selection and compliance. A near-zero liquid discharge (ZLD) wastewater treatment system was determined to be the best compliance option. Various options were evaluated to help select the most economical treatment configuration. The selected technology is currently under construction.

Introduction

will be returned to the plant for reuse, and concentrated brine will be routed to new evaporation ponds. Various options were evaluated in an initial study phase to help select the most economical treatment configuration, including the following aspects: Makeup water softening.

High-efficiency reverse osmosis (HERO).

Nanofiltration (NF).

Closed-circuit RO.

Cherokee Generating Station, located in Denver, Colorado, and operated by Xcel Energy as Public Service Company of Colorado, is a steam electric generation station that consists of one 335-megawatt (MW) unit burning natural gas in a boiler originally designed to burn coal (Unit 4), a 2 x 1 natural-gas-fired combined cycle producing 612 MW (Units 5, 6, and 7), and a unit converted to a synchronous condenser (Unit 2) providing electric grid stability service. Two other units at the plant are permanently retired (Units 1 and 3), but still have structures that collect stormwater that ultimately combines with other plant wastewater and stormwater across the site.

Forward osmosis.

Wastewater produced at the plant includes cooling tower blowdown, reverse osmosis (RO) system reject, stormwater, and other miscellaneous plant wastewaters.

The plant has treated wastewater prior to discharge for approximately 20 years with clarification followed by polishing ponds for additional solids settling, resulting in a treated effluent suitable for discharge. In 2019, the plant was given new National Pollutant Discharge Elimination System (NPDES)/Colorado Discharge Permit System (CPDS) permit limits for chlorides, sulfates, TIN, and other constituents for the plant’s common outfall to the South Platte River. The permit requires compliance with the new limits beginning in early 2022.

Evaporation ponds.

Ultra-high-pressure RO. Membrane electrodialysis.

Osmotically enhanced RO. Mechanical vapor recompression evaporator.

Forced circulation crystallizer.

Alternative thermal evaporator designs.

Waste heat cooling tower.

Bypass evaporator spray dryer.

Operational changes.

Discharge to a nearby publicly owned treatment works (POTW) facility.

Due to the new NPDES limits, Xcel Energy, with the assistance of the engineering company,A determined that a near-ZLD wastewater treatment system was the best option for the plant to replace the existing conventional clarification system. Treated water from the new system 37

The wastewater treatment project was designed in 2019, with construction beginning in 2020 and completed in late 2021. Startup and commissioning activities began in late 2021 and continued into early 2022. This article will cover the following aspects of the initial study and detailed design phases of the wastewater treatment system: Study phase options considered and drivers for the near ZLD system selected. the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

“The worst-case wastewater quality was considered during the study phase for sizing and selection of the wastewater treatment equipment.”

Process description and design considerations/ limitations of equipment selected.

A methodical approach to evaporation pond selection/ sizing.

Operational changes to reduce wastewater flow requiring treatment.

residual chlorine neutralization, and polishing ponds for suspended solids removal. After treatment, all process wastewater and stormwater discharges through a common outfall to the South Platte River.

Challenges of elevated total organic carbon (TOC) in wastewater, its effects on selected wastewater equipment, and TOC removal methods evaluated.

Summary/conclusions and key next steps.

Study Phase

The existing Cherokee Power Plant receives makeup water from a variety of sources. These include Copeland Reservoir (Clear Creek), the South Platt River (York Street and South Diversion), Denver Water POTW Reuse, and Denver Water potable. Makeup water quality from the different sources was considered as part of the study evaluation. Some source waters are typically only available during portions of the year (Copeland Reservoir and South Platte River). Xcel must take some wastewater from the Denver Water Reuse in the winter months as the primary users of this tertiary treated wastewater are golf courses that do not need water in the winter months.

Xcel recently received its renewed CPDS wastewater discharge permit for Cherokee Generating Station.

The revised CDPS permit requires the plant to comply with more stringent discharge requirements beginning in 2022. Its revised permit resulted in more stringent limitations on temperature, E. coli, selenium, TIN, chloride, and sulfate, and a new requirement to measure cooling water intake flow. Cherokee will not be capable of meeting the new constituent discharge limits with the existing wastewater treatment system. Through evaluation of the water quality data available and discussions with Xcel, the revised permit limits for TIN, chloride, and sulfate were identified as the constituents of concern.

The other permit revisions were determined to be nonconsequential. Table A summarizes the key permit limits that impact the plant.

Compliance for the new TIN limits was required by end of 2021, whereas compliance for the new chloride and sulfate limits is required by the end of 2022. Xcel decided that the wastewater treatment solution should be in service by October 31, 2021, allowing for time to start up and commission the new equipment before the new TIN limits take effect.

The plant essentially uses Copeland Reservoir water in the summer months and Denver Water Reuse water in the winter months. The worst-case wastewater quality was considered during the study phase for sizing and selection of the wastewater treatment equipment.

All process wastewater and stormwater are currently passed through a wastewater treatment system that includes metals precipitation, bisulfite addition for Table A: Key New Permit Limits for Cherokee Station Parameter

Old Limit

New Limit

Unit

Type

Condition

Temperature

Report

Varies by Month

°C

7-day average

Begin 1/1/2031

TIN

20

10

mg/L as N

Daily maximum

Begin 1/1/2022

Chloride

Report

250

mg/L

30-day average

Begin 1/1/2023

Sulfate

Report

533

mg/L

30-day average

Begin 1/1/2023

38

the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

Compliance options were evaluated during the study phase. The flow rate for the new wastewater treatment equipment was estimated to be 1.5 million gallons per day (MGD) for process wastewater. This included wastewater flows from various sources, including cooling tower blowdown, boiler blowdown, and quench water, heat recovery steam generator (HRSG) blowdown and quench water, service water cooling tower blowdown, and stormwater. The 1.5 MGD treatment was selected as a representative wastewater flow rate based on Xcel’s historical data monitoring wastewater discharge flows.

A wide variety of approaches for complying with the more stringent permit limits was considered during the study phase. These approaches were organized into four compliance approach categories, as listed here:

approaches were narrowed down to four options for comparison: 1. NF and RO treating just process wastewater.

2. NF and RO treating process wastewater and stormwater.

3. Separation of stormwater from process wastewater and treating process wastewater with NF and RO. 4. Discharging all process wastewater and stormwater to Denver Metro.

During the project execution phase of the project, the flow rate for the new wastewater treatment equipment was revisited. Xcel had been investigating operating the cooling towers at higher cycles of concentration, reducing the cooling tower blowdown. Xcel had also discovered and eliminated other miscellaneous wastewater flows being treated. In the end, a treatment rate of approximately 1.0 MGD (700 gallons per minute [gpm]) was selected as the design basis for the new wastewater treatment system.

1. Cooling Tower Makeup Pretreatment a. Cold lime softening b. NF softening 2. Wastewater Treatment Volume Reduction a. HERO b. NF c. Closed circuit RO d. Forward osmosis e. Ultra-high-pressure RO f. Membrane electrodialysis g. Osmotically enhanced RO

The compliance option selected was a combination of technologies resulting in a near-ZLD treatment system.

Treatment for compliance with the new chloride and sulfate discharge limits proved to be the most challenging aspect for the new wastewater treatment system.

Dissolved chloride salts are very soluble and difficult to precipitate out from solution. Membrane-based and thermal-based treatment options were favored because of the difficulty in treating and reducing/removing chlorides from the wastewater. Both types of technologies allow for reuse of the treated water in the plant, effectively reducing the amount of makeup water required. The net present cost, including total installed costs and annual operating costs, was calculated for each alternative. In the end, the membrane-based alternatives were more economical than the thermal-based treatment options.

3. Evaporation Technologies a. Traditional evaporator b. Crystallizer c. Modular evaporator d. Thermal evaporator/crystallizer e. Evaporation ponds f. Waste heat cooling towers g. Bypass evaporator spray dryer 4. Operational Changes a. Decommission Unit 4 earlier b. Reduce cooling tower cycles of concentration c. Increase cooling tower cycles of concentration

Detailed Design Considerations

The wastewater technology selected was chosen from three primary wastewater treatment vendor offerings: 1. conventional softening clarification coupled with multiple RO passes; 2. ultrafiltration coupled with HERO; and 3. high-rate softening clarification followed by multimedia filters and close-circuit RO.

In most cases, a single-compliance approach was not sufficient to meet the revised CDPS limits, so multiple compliance approaches were partnered to create overall treatment solutions. These potential compliance 39

the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

“Treatment for compliance with the new chloride and sulfate discharge limits proved to be the most challenging aspect for the new wastewater treatment system.”

The wastewater treatment system ultimately selected and designed includes equalization ponds, high-rate softening clarification, multimedia filtration, closed-circuit RO with 98% recovery of wastewater for treated water reuse, evaporation ponds for concentrated brine, stormwater conveyance and detention systems, and filter press for sludge dewatering (existing filter press reused). The system was designed to operate in two modes—either 24-hour yearly average flow of 350 gpm or maximum design flow of 700 gpm—utilizing a control valve adjust inlet flowrate. Key drivers for selection of the wastewater treatment system included optimization and utilization of existing water treatment building space available, equipment capital cost, total installed cost, wastewater quality performance guarantees for discharge of effluent as required, and minimization of RO reject flow rate given evaporation pond sizes.

The process description for this system begins with collecting various plant wastewater and stormwater flows into an existing lift station, which will be retrofitted with larger pumps to adequately handle rerouted stormwater flows. The preliminary process flow diagram is shown in Figure 1. The lift station pumps wastewater to a network of two equalization ponds. The equalization ponds allow for wastewater equalization to dampen fluctuations in wastewater pH and other water-quality parameters, as well as provide some storage of wastewater for ease of scheduling wastewater treatment system operation for set periods of time.

Figure 1: Xcel Cherokee wastewater treatment preliminary process flow diagram.

3

2

1

5

4

6

7

8

9

10

11

12

13

15

14

LEGEND: BLUE = EXISTING EQUIPMENT OR FLOW PATH

NW Reservoir

U7 Storm Water

U7 Cooling Tower

RED = NEW EQUIPMENT OR FLOW PATH

West Storm Water Pond 0.5 Acre

Clear Creek / Copeland Denver Metro / Reuse / S. Platte

U7 Process Drains

U4 Process Drains

U4 Cooling Tower

~7 COC

U1-4 Service Water Towers

U1-4 Storm Water

A

NOTES: 1. NC = NORMALLY CLOSED 2. AUXILIARY (WASTEWATER) COOLING TOWER NO LONGER REQUIRED. 3. BISULFITE INJECTION REQUIRED TO TREAT RESIDUAL CHLORINE ONLY IN EVENT NW RESERVOIR OVERFLOWS.

B

South Side Storm Water Pond

~6 COC

C

U7 RO System

Emergency Overflow Pond 0.4 Acre (Relined)

Millimeters

U4 RO System

D

Scale For Microfilming

Bisulfite Injection [3] E

CB-20

Lift Station A

Existing WWT Plant

1.1MGD 764gpm Inches

EQ Pond ~3 Acre, 10' 10 MGal

NC F

Evap Pond ~3.8 Acre

11gpm Reject

MMF, NF, RO

753gpm Perm.

1MGal Treated Tank

#1 #2 #3 #4

-

Polishing Ponds 2x ~2 Acre (Relined)

RO Makeup Cooling Tower Makeup NW Reservoir Discharge to River

NC

98.5% Rec

G

Outfall 001a

H

PRELIMINARY - NOT FOR CONSTRUCTION

Wastewater is pumped from the equalization ponds to the head of the wastewater treatment process—the highrate softening clarifier. Following clarification, wastewater overflows to a clearwell tank, where it is then pumped through multimedia filters to a filtered water tank, which serves as the feed tank to the closed-circuit RO membranes.

PFD-003 Permeate from the RO skids is directed to a break tank with forwarding pumps to the treated water storage tank for reuse in the plant.

CHEROKEE GENERATING STATION PROCESS FLOW DIAGRAM SOLUTION #3 - MMF + NF + RO

project

B

05/03/19 LEE

A

04/12/19 LEE

no.

date

by

BDH

OWNER COMMENTS INCORPORATED

BDH

ISSUED FOR REVIEW

ckd

9785 MAROON CIRCLE CENTENNTIAL, CO 80112 303-721-9292

description

no.

date

by

ckd

description

40

designed L. ELLINGSON

detailed L. ELLINGSON

the ANALYST Volume 29 Number 2

contract

N/A

113103

drawing sheet file

1

of

1

rev.

B

sheets

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Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

“Evaporation pond size was a key design consideration, given the limited existing space at the Cherokee facility.”

The RO reject stream is directed to either of two evaporation ponds. Backwash from the multimedia filters is directed to temporary storage in a backwash wastewater tank and is then directed back to the head of the process.

A portion of sludge from the high-rate clarifier is recirculated back to the clarifier to maintain adequate solids in the clarifier, with the sludge ultimately being pumped to sludge holding tanks and the existing filter press for dewatering and removal by truck.

Existing ancillary support systems for compressed air and potable water were upgraded as part of the project.

A new clean-in-place (CIP) system was also provided for periodic maintenance cleanings of the RO system.

Evaporation pond size was a key design consideration, given the limited existing space at the Cherokee facility.

As discussed in the following text, two evaporation ponds were ultimately determined to be required, with their size driven directly by the flow rate of the RO reject stream.

Closed-circuit RO recovery rate was a key consideration, given the destination of closed-circuit RO reject in the evaporation ponds and no additional space for evaporation being available due to equalization ponds also being required to capture miscellaneous stormwater reroutes and plant wastewater flows for treatment. The evaporation pond sizing assumed a maximum closed-circuit RO reject flowrate of only 2% of the incoming wastewater at a maximum design flowrate of 700 gpm. Conservatism was built into the maximum 700 gpm flow rate as the plant will not operate under this condition continuously for long periods of time. In addition, the 700-gpm maximum wastewater flow rate is expected to be even more conservative following additional operational changes to reduce cooling tower blowdown and the possibility of retiring the Unit 4 boiler, as discussed later in the article.

RO system considerations are similar whether the system is more standard performance RO or higher performance closed-circuit RO. However, there are some 42

differences required for RO. In particular, the following are important design parameters that had to be carefully evaluated to confirm RO performance (guaranteed 98% recovery rate) under all operating conditions: TOC and fouling potential, as discussed later.

Design temperature, with higher temperatures (104 °F and above) resulting in lower recovery rates. The RO original equipment manufacturer (OEM) provided recovery rate temperature correction curves for higher temperature operations.

Potential maximum silica concentration in wastewater necessitated the provision of a magnesium chloride chemical feed system to the high-rate clarifier.

This chemical feed is expected to be required only periodically if silica concentration is sufficiently high and magnesium concentration is also on the lower end of the design range.

Optional two-pass operation of RO systems was included in the design. This functionality provides extra contingency on producing even higher purity water than the normal single-pass operation for cases when treated permeate cannot be used in the plant and must be discharged to the plant outfall. When the system operates in this mode, permeate from the first pass is sent to the CIP tank and then fed to the RO skid designated as the second-pass skid. Operating in this two-pass mode results in reduced capacity, as each of the 3 x 50% RO skids is only rated for 350 gpm. However, this mode is only expected to be used when the plant is not operational and the equalization ponds are full.

Management of treated water reuse in the plant was a key consideration that led to the wastewater treatment system classification as near-ZLD. A one-million-gallon treated RO permeate water storage tank was provided with forwarding pumps to feed various existing plant water users. The treated water users in the existing Cherokee plant include makeup water for the Unit 4 and Unit 7 RO systems, Units 5 and 6 the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

Evaporation Pond Sizing

evaporative cooler makeup water tank, and makeup to three cooling towers.

When the plant is operational most of a given year, there will be limited or no discharge on average. When the plant is shut down for extended periods, stormwater flows still need to be treated by the wastewater treatment system, so there is some potential for discharge.

Thus, classification as zero liquid discharge could not be achieved for this system. Additional flexibility was designed into the system to allow treated water to be pumped from the storage tank to the equalization ponds for additional storage, drained from the tank to the outfall, or for permeate to be pumped directly to the outfall.

Stormwater management was found to be a key limitation for the overall system during the design. Following a detailed review of stormwater flow and concentration timing following reroutes, it was found that significantly larger lift station pumps were required to adequately handle pumping duty during the peak flow of design storm events. Although the plant has an emergency spill pond that can receive overflow from the lift station under certain scenarios, discharge from the spill pond is to be normally avoided and requires special correspondence with permitting agencies prior to discharge. The equalization and evaporation ponds also had to be designed with suitable design storm events in mind.

Evaporation ponds for RO reject were required to be located somewhat remotely from the wastewater treatment building given the layout of the existing plant site. Although the high-pressure recirculation pumps provided with the RO skids produce more than adequate pressure for RO reject to be pumped a significant distance and elevation away, the standard OEM design is to ramp down the recirculation pump and throttle RO reject flow to reduce discharge pressure to near atmospheric for discharge to building drains or trenches. As such, careful coordination was required between the OEM RO system and the interconnecting piping design to ensure adequate pressure would be maintained to pump reject to the evaporation ponds and that pressure instrumentation would be provided to permit suitable start-up tuning and operations.

43

Sizing of the evaporation ponds considered numerous factors, including historical/projected unit operating hours; number of units in operation; space available for new ponds; surface area; water volume; wastewater salinity; and site ambient conditions, such as wind speed, precipitation, and evaporation rates. Three potential operating scenarios were evaluated—minimum, typical, and maximum capacity. Each scenario involved different combinations of units operating and offline. The primary difference was in the length of time each unit was projected to be operating.

Annual average evaporation rates using pan evaporation data for the area was calculated and then adjusted by a factor to account for the elevated salinity levels of the wastewater in the evaporation ponds. At higher salinity levels, the evaporation rate is reduced.

Nine potential pond sizes were evaluated in addition to combinations of various ponds. A time-weighted analysis was performed to determine how long each evaporation pond or combination of ponds would fill up over time.

This analysis determined several potential pond combinations that could receive the wastewater from the plant and not run out of volume. The final evaporation pond sizes and locations were determined from this effort.

Operational Challenges

Xcel identified several potential areas where they could reduce wastewater flows from the plant. The main areas were the Unit 4 and Unit 7 cooling towers that could operate at higher cycles of concentration and reduce blowdown. In addition, the plant has service water cooling towers that are used to reject heat from balance of plant loads outside of the boiler and the HRSG. The service water cooling towers were operating in nearly a once-through cooling mode that generated a lot of wastewater for treatment. Heat loads were shifted from the Unit 1/2/3 service water tower to the Unit 4 service water tower, which is more efficient and reduced the quantity of wastewater generated.

The plant also investigated other areas where excess wastewater was being generated, and reduced or eliminated many of these sources. For example, the plant found one valve that was leaking, creating additional process wastewater for treatment. The valve was replaced, the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

which consequently reduced the volume of wastewater generated for treatment. Unit 4 is scheduled to retire in the near future, which will also reduce the quantity of wastewater generated at the plant.

grouped into three large categories: treatment of incoming wastewater to remove TOC, acceptance of increased CIP operations, and fouling risk mitigation by modifications to source water and RO equipment.

Elevated TOC Considerations

TOC treatment with granular activated carbon (GAC) adsorption on the incoming wastewater was investigated in detail by both the engineering company and the wastewater treatment system OEM. GAC is a well-established means of removing TOC from water. The process itself is relatively simple and is like filtration processes that involve multiple vessels in parallel service. The chief difference is that the activated carbon adsorbs TOC, rather than simple physical filtration impingement, and thereby requires replacement of carbon media once exhausted, as compared to backwashing for removal of accumulated solids.

TOC is a known potential foulant to RO membranes but is not always a significant consideration in wastewater treatment design, as it relates to steam electric power plants. TOC is generally associated with surface water sources. It can also be found in significant concentrations in gray water, or as in the case of the Xcel Cherokee plant, even POTW discharge, which is one of the makeup water sources to the plant for a portion of the year.

During detailed design of the wastewater treatment project, TOC was flagged as a possible concern, but no historical data was available on the plant wastewater TOC content. Xcel Energy requested historical data on the city of Denver POTW wastewater source, and the data was analyzed by the engineering companyA to find an average TOC concentration of 8 to 10 parts per million (ppm). In addition, Cherokee plant staff worked to obtain and analyze wastewater samples from the cooling towers for analysis while the plant was accepting Copeland reservoir water as makeup. The plant wastewater samples showed a TOC concentration of approximately 25 to 30 ppm on average, indicating the effect of cooling tower cycle up of the influent TOC. Considering cooling tower cycles of about four to five cycles at the time of the wastewater samples, the Copeland source water average TOC concentration was calculated to be similar to the city of Denver POTW value of 8 to 10 ppm.

The closed-circuit RO maximum acceptable TOC value to avoid performance impacts due to significant fouling specified by the OEMB is 5 ppm, with 3 ppm or less indicated as optimal. Thus, the expected influent wastewater TOC concentration of 25 ppm has the potential to cause significant fouling in the RO systems, thereby impacting recovery rate and likely putting the evaporation ponds at risk of overflow due to additional reject wastewater production. As such, Xcel Energy, the engineering company, and OEM began a detailed study of options to mitigate the TOC issue. The options for addressing TOC investigated for the Xcel Cherokee system can be

The rate of exhaustion of GAC media is determined by laboratory testing or piloting of a given GAC product/ media until breakthrough of organics is detected on the effluent water. Xcel Energy supplied both the OEM testing laboratory and an independent testing laboratory coordinated by the engineering company with wastewater samples in fall 2020 for the purpose of GAC testing on the Xcel Cherokee specific plant wastewater.

It is important to test multiple carbon types and sources during such laboratory testing to ensure an adequate data set, and to identify any carbon lines, which would be expected to perform better than others.

Both the OEM laboratory and independent laboratory coordinated by the engineering firm found relatively rapid GAC exhaustion rates across various product lines of GAC, indicating very frequent replacement of GAC media would be required to adequately remove TOC below the target levels of less than 3 ppm. Media replacement was calculated to be required every 3.5 to 4.5 days at the maximum design flow of 700 gpm, given the GAC tested adsorbed between 2.09 and 2.48 pounds of TOC for every 100 pounds of GAC. Table B presents a comparison of GAC treatment and increased CIP frequency costs.

Higher frequency CIP operations to remove potential TOC fouling from the RO membranes were also considered rather than removing TOC from the wastewater via active treatment equipment. The engineering company contacted membrane suppliers regarding recommendations and technical background on TOC fouling of

44

the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

membranes. In general, membrane fouling potential depends on what type of organic molecules make up the TOC content in the wastewater. TOC concentration alone does not provide enough information to predict the fouling rate of the membranes, how receptive the membranes are to cleaning, nor the level of rejection of TOC through the membranes.

Different types of organic molecules have general fouling potential as follows: Simple alcohols (e.g., ethanol) are low molecular weight (MW) alkanes and do not damage the RO membranes or foul it.

On the contrary, higher MW organics that are larger than approximately 9 Angstroms tend to foul membranes while having 99% or greater rejection rates. Designing RO systems upfront with lower average flux of approximately 12 gallons per square foot per day (gfd) can be helpful in reducing the fouling potential for higher TOC applications. It is worth noting that to achieve higher rejection of smaller MW organic molecules, very consistent cross-linking across the entire membrane roll is required. This is difficult to consistently achieve in practice, depending on manufacturing methods, as the membrane polymer material is cast onto the polysulfone backing material at a rather high speed.

Pilot testing of wastewater with given RO membranes, which also includes CIP trials, is the best method for completely understanding the expected performance of membranes with the specific organics in the wastewater stream. However, pilot testing was unable to be completed due to project schedule constraints. Instead, Xcel Energy determined that an evaluation of the system performance would have to be made during initial startup and operations, as well as operationally tested during that time, with any measures to reduce fouling risk taken in advance.

Oils and greases are typically very significant foulants if present in concentrations above their respective solubility limits and are nearly impossible to clean from membranes.

Organic solvents are generally a concern when present in greater than trace amounts. They typically and irreversibly soften the polysulfone backing layer of membranes.

Antifoaming agents and surfactants are typically a fouling concern and can also be difficult to clean from membranes.

Cationic flocculant aids tend to foul and are very difficult or nearly impossible to clean from membranes.

Aldehydes may be a fouling concern if any unreacted amines are present in the RO membrane.

Overall, TOC, which comes from natural organic matter, tends to be larger and more complex (e.g., tannins) with higher MW values. RO membranes consist of a crosslinked polymer matrix that contains interstitial spaces with approximate diameters generally in the 4 to 6 Angstrom range. Smaller or intermediate MW (MW of approximately 60 to 150 grams per mole [gm/mol]) organic molecules in the 4 to 8 Angstrom size range tend to have lower rejections rates in the 70 to 75% range but do not tend to foul membranes, as the molecules are small enough to pass through the membrane interstitial spaces.

Given past engineering company experience on a source water treatment project involving poor quality and high-TOC bayou water that included higher MW TOC with the highest fouling potential, assumptions were made to determine the cost of running CIP operations more frequently at Xcel Cherokee to remove TOC fouling to compare with the cost of TOC removal via other means already discussed. The engineering company conservatively assumed CIP would be required once per week and that full membrane replacements would be required every two years. Table B presents a comparison of GAC treatment and increased CIP frequency costs.

A change in plant makeup water source was also considered by the engineering company, given the difference in makeup water sources available at the Cherokee plant. Although the concentration of TOC in both the Copeland Reservoir surface water source and the city of Denver POTW treated effluent water source are relatively similar, the characteristics and size of the organic molecules comprising the TOC is expected to be significantly different.

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the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

“Capital and operating costs for a GAC treatment system were evaluated by the engineering company to be substantially higher than even rather frequent CIP operations.”

Although Xcel Energy and the engineering company were unable to have a TOC speciation performed on the plant wastewater due to difficulty finding laboratories that could perform the analysis, the level of treatment involved in the POTW effluent water as compared to the Copeland reservoir surface water very likely results in much smaller MW organics comprising the TOC content of the POTW effluent. Thus, the POTW effluent is expected to result in RO membrane fouling that is easier to clean as compared to larger MW organics expected in the Copeland reservoir surface water. As such, the engineers recommended, and Xcel Energy agreed, that switching to city of Denver POTW effluent year-round was advisable to mitigate the potential for RO fouling.

The rejection rate of TOC from the closed-circuit RO membranes was also considered in the recommendation to switch plant makeup water sources. Given the expected influent wastewater TOC concentration of 25 to 30 ppm, and assuming 75% rejection of TOC through the RO, the effluent TOC concentration would be in the 6 to 8 ppm range, which is very similar to the concentration of TOC in the plant makeup water from the city of Denver POTW. Since the treated water will be reused in the plant as makeup water to boiler demineralized makeup water systems involving RO, as well as cooling tower makeup water, the TOC concentration of the RO permeate quality being similar or better than the plant makeup water is an important consideration. In addition, when the RO permeate must be discharged under rare circumstances, the plant does not have an NPDES discharge permit limit value for TOC, so the TOC concentration in the discharge would not be a concern, even if the actual rejection rate of TOC is found to be lower during actual system operation.

RO membranes rated for high-TOC waters are available from a few membrane suppliers. The upfront cost of these membranes is somewhat higher, and testing is recommended to confirm their actual performance with a given water prior to investing the capital for a full set of membranes for multiple RO passes and/or redundant trains. Due to the lack of sufficient project schedule for piloting of higher TOC membranes, Xcel Energy and the RO OEM agreed to install higher TOC membranes

in one of the three RO skids with more standard higher TOC membranes in the other RO skids. The performance of the high-TOC rated membranes relative to the standard membranes will be evaluated during initial system startup and operations to determine if high TOC membranes are a worthwhile investment for all the RO trains.

Capital and operating costs for a GAC treatment system were evaluated by the engineering company to be substantially higher than even rather frequent CIP operations. This led Xcel Energy to determine that installation of a GAC treatment upfront without first evaluating how the system would perform was not economically advisable. However, provisions were made for inclusion of a removable flanged spool that could be replaced in the future to make installation of piping to and from a future GAC treatment simpler if this step was later found to be recommended. Table B compares the costs of GAC treatment/removal of TOC and higher frequency CIP operations with reduction in membrane life. The table presents the following data: New GAC filters with operation at the minimum wastewater design flow rate of 350 gpm (first row).

New GAC filters with operation at the maximum wastewater design flow rate of 700 gpm (second row).

Estimated additional operating costs for increased RO membrane replacements and CIP cleanings (third row). More frequent CIP will reduce membrane life.

Note that this operations & maintenance (O&M) cost is only for the incremental additional cost above and beyond the base operating costs for the rest of the wastewater treatment system, not the total expected wastewater treatment system O&M cost.

46

the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

Table B: Comparison of GAC Treatment and Increased CIP Option Costs Capital

O&M

NPV

Total Levelized Cost

Option

Viable

(2020$)

(2020$)

(2020$)

$/yr (2020$)

New GAC filters; regular RO operation; minimum GAC replacement

Yes

$1,225,000

$1,390,000

$23,461,000

$2,045,000

New GAC filters; regular RO operation; maximum GAC replacement

Yes

$1,225,000

$3,849,000

$62,801,000

$5,475,000

No GAC; increased CIP; membrane replacements

Yes

$0.00

$242,000

$3,878,000

$338,000

The selected solution for high TOC was to operate CIP more frequently and replace RO membranes more often, as needed. This was determined, given the considerations described above, which show that the use of GAC treatment upfront was a higher capital and O&M cost option that might not be required and should only be implemented following confirmation of the original wastewater treatment system performance. Xcel made the decision to help mitigate the risk of TOC fouling by also switching the plant makeup water source to the city of Denver POTW effluent year-round. The wastewater treatment system OEM also agreed to supply one set of higher TOC rated RO membranes for testing during the startup and initial operational period. The frequency of CIP washes as well as the effectiveness of various CIP solutions (e.g., high pH, low pH) will be determined during system startup and initial operations, and adjustments to cleaning solution and frequency will be made as required.

Summary and Conclusions

Selection and design of a new wastewater treatment system for discharge permit compliance needs to consider a wide variety of factors, including treatment rate, optimization of existing plant operations, planned future unit operations, and sources of plant makeup and water quality for each source.

Equalization of inlet wastewater not only helps balance out the required system treatment rate, but it also reduces variability in the wastewater quality from different wastewater streams.

Knowing the potential makeup water sources and seasonal variability in the use of these sources, as well as the variability in the quality of each source, is required to determine a reasonable design basis for the wastewater treatment system design.

A combination of various treatment technologies is likely required to achieve the overall project objectives in the most economical way.

Selection of the wastewater treatment technology should be based on a new present cost analysis, including cost of equipment, installation cost, and annual operating costs levelized out over the life of the project.

Sizing of evaporation ponds should consider ambient conditions, precipitation, evaporation, and realistic operating conditions, as well as salinity of the wastewater.

System design should consider operational flexibility with adequate equipment redundancy as needed to provide reliable operation.

Optimization of existing plant operations can reduce the required volume of wastewater for treatment, subsequently reducing the cost of wastewater treatment.

Knowing projected unit operating hours per year can also reduce the size of the required wastewater treatment system by not oversizing equipment for unlikely operating conditions (e.g., designing the wastewater system for full flow operation for 24 hours/ day of the year is overkill).

47

System design should provide operational contingencies (e.g., when the system needs to run but not return recovered water to the plant). Make sure the treated wastewater can be discharged.

Management of how stormwater is handled needs to be integrated into the system design.

the ANALYST Volume 29 Number 2

Areas to Consider When Designing a Near-ZLD Wastewater Treatment System continued

“Depending on the initial performance evaluation during startup, procurement of higher TOC-rated membranes may be warranted, assuming performance is notably improved over standard membrane offerings.”

or on the plant wastewater stream prior to the newly installed treatment system (which would be a lower flow/ higher TOC concentration application).

Endnotes

A Burns & McDonnell is the engineering company referred to throughout the text.

B Suez Water Technologies and Solutions is the OEM mentioned in the text.

Obtain full water-quality analysis of each potential makeup water source as early as possible to help identify potential design considerations, like elevated TOC.

Key Next Steps

The important next steps for the Xcel Cherokee near-ZLD wastewater treatment system includes a successful system startup and initial operational tuning to meet performance guarantees and permit limits, led by the OEM onsite startup team, with engineering company support. Education of Xcel Energy operators during this process and a successful turnover from the OEM startup team to Xcel Energy operations is of paramount importance. Another key next step will be managing the use of treated water reused in the plant against the possible need for discharge to the outfall as well as managing evaporation pond levels, depending on actual evaporation rates and environmental factors.

Paul T. Brandt, P.E., is a senior chemical engineer with Burns & McDonnell. His 14 years of power industry experience includes water and wastewater aspects of various system,s such as physical/chemical/biological treatment with ZLD for wet scrubber blowdown, demineralized water treatment, air quality control equipment, bottom ash handling, and CCR pond closures. Mr. Brandt can be reached at pbrandt@burnsmcd.com.

Bryan D. Hansen, P.E., is a senior associate chemical engineer for Burns & McDonnell in the Energy Division. Mr. Hansen has 30 years of experience working on projects involving water/wastewater treatment process design and air pollution control equipment process design. Mr. Hansen graduated from the University of Missouri-Columbia in 1991. He can be contacted at bhansen@burnsmcd.com.

Another crucial future step will be evaluating the suitable CIP frequency and various chemical solution performances, given the potential for TOC to foul the RO membranes. Depending on the initial performance evaluation during startup, procurement of higher TOC-rated membranes may be warranted, assuming performance is notably improved over standard membrane offerings.

A membrane autopsy report is also planned on fouled membranes—both standard and higher-TOC varieties— during startup to confirm the primary foulants and failure mechanism.

Another possible future evaluation step would be a new study and possible capital project to remove TOC should the RO cleaning frequency turn out to be overly burdensome for the Xcel Energy operations team. This study would need to consider whether TOC treatment would be best installed on the incoming plant makeup water (which would be a higher flow lower TOC application) 48

Jason Miller is a system chemist at Xcel Energy’s Cherokee Station in Denver. He also is the Class A industrial wastewater operator in charge at the Cherokee Station and the Valmont Station (Boulder, Colorado). Mr. Miller has 20 years of experience in coal/HRSG/nuclear boiler water chemistry. He has a B.S. in applied science and technology (BSAST) in nuclear engineering technology from Thomas Edison State College. Mr. Miller may be reached at jason.r.miller@xcelenergy.com.

Adam Kortan is a chemist at Xcel Energy where he is responsible for management of the boiler water, cooling water, and wastewater programs of the Cherokee Station power plant in Denver. Mr. Kortan holds a bachelor’s degree in chemistry from Grinnell College and a master’s degree in materials science from Colorado School of Mines. He may be contacted at Adam.M.Kortan@xcelenergy.com.

This paper was originally presented at the International Water Conference, which was conducted November 7–10, 2021, in Scottsdale, Arizona. More information about the IWC and future meetings is available at www.eswp.com.

The article is published with the permission of the IWC.

the ANALYST Volume 29 Number 2

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“The water safety and management plan should include procedures and monitoring to ensure that hot water systems are circulating and fulfill the balancing requirements set forth in ASHRAE Standard 188 Section 8.”

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the ANALYST Volume 29 Number 2

Practical Tips for Troubleshooting Wastewater Pretreatment Systems Amanda Meitz, Biosolutions, LLC

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Introduction

Water treatment professionals working at food or manufacturing facilities where they already provide water treatment or clean-in-place chemistries may become effective contributors to the wastewater pretreatment system. Plant personnel who work in manufacturing, food, beverage, and chemical plants are deeply engaged in producing the many products the rest of us consume or use daily and often take for granted. An important role for water treatment personnel can be in helping management understand that the pretreatment system is not only a cost center but potentially a (admittedly) small revenue source.

Evaluating the influent and performance of the pretreatment system can assist in targeting specific production areas where investment in system improvements can be justified.

The purpose of pretreatment systems at production plants is to protect the publicly funded water resource recovery facilities (WRRF) from highly concentrated waste effluent these facilities are not normally designed to treat. The U.S. Environmental Protection Agency (EPA) lists a group of conditions that require pretreatment facilities be built and maintained that are often monitored by pretreatment coordinators who work for the receiving WRRF. This article includes suggestions for evaluating unit operations and calculating nutrient ratios, hydraulic retention time, and sludge age or mean cell retention time. It also includes photomicrographs of helpful and less desirable microbes. At the end of the article, there is a glossary of useful terms associated with wastewater treatment.

Problems—not meeting discharge requirements?

Odor?

High operating cost?

Are one or more of the unit operations not working as well as they should?

These are examples of the types of technical information that representatives routinely develop for cooling or heating applications. They are also relevant to examine when researching operational problems with a wastewater pretreatment system.

2. Obtain the discharge requirements for the pretreatment system—state or federal National Pollution Discharge Elimination System (NPDES) permit or the permit from the WRRF. These are the requirements for successful operation and may provide a structure for operational improvements in production areas or at the pretreatment facility. Discharge under an NPDES permit for biochemical oxygen demand (BOD) may be 20 to 30 milligrams per liter (mg/L). Discharge permitted by a large WRRF may be 500 mg/L BOD, or not specified, or expressed as pounds per day (lb/day), with substantial surcharges required for BOD more than the listed lb/day.

3. Obtain a schematic of the piping from the waste sources to the effluent point where it leaves the plant. It may be your sketch, or it may be from the engineers’ drawings of the plant design. Note that unless the pretreatment system is new, the engineers’ drawings may need to be updated because components have been added or modified.

Describe the Existing System

When troubleshooting a wastewater system, begin with a description of the current system. This will help the water treatment professional to better understand system operations, the types of treatment equipment, and where problems may occur. Here are action steps for understanding the system:

4. Fill out a chart to help think about the working parts of the system. Some equipment will be there; other equipment may be different or absent. Table A provides a guide.

1. Survey for available information as you investigate for possible solutions. Here are examples of questions to consider:

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continued

Table A: Typical Unit Operations Sometimes Found at Pretreatment Facilities Unit Operation

Goal/Purpose of Equipment

Product

DAF

Oil separation

Oil for sale or convert to diesel

Oil Skimmer

Oil separation

Oil

Screens

Large solids removal

Grit, generally goes to landfill

Filters

Smaller solids removal

Grit, to landfill

pH adjustment

Put pH into biological range

pH 6–8 water

Equilibration tank

Mix high/low concentrations, high/low pH or dilute

Wastewater for further processing

Anaerobic lagoon

Process high concentration BOD to methane for cogen plant

Organic acids, CO2, CH4

Activated sludge tank

Convert soluble BOD to biomass.

Nitrification, NH3 NO2 NO3

RAS and WAS Decrease NH3 toxicity

Anoxic tank

Denitrification, NO3 N2

Soluble N removal

Clarifier

Separate solids from liquids

Sludge—RAS or WAS Water that meets requirements

UF or RO membranes

Separate solids from liquids

WAS Water that meets requirements

Sand filters

Solids removal, polishing

Low TSS water to discharge

Chlorination

Disinfection

Low microbial numbers to discharge

Dechlorination

Remove chlorine

Less toxicity for stream organisms

UV treatment

Disinfection

Low microbial numbers to discharge

Sludge thickening tank

DecantActivated sludge SolidsFurther processing

Decant for reprocessing Solids to sludge cake typically

Sludge press

Sludge cake

Potential use as fertilizer, or landfill

Sludge vacuum filter

Sludge cake

Potential use as fertilizer, or landfill

Look for Sustainability Opportunities Look for opportunities early in the treatment process to reclaim raw materials before they go to the wastewater treatment process. Beneficial uses include animal feed supplements, fuel, fertilizer, or possibly other uses.

Keeping track of the material that is reclaimed can help provide justification for process improvements, such as capital equipment that will allow more of the raw materials to be included in the products, which will alleviate the load at the pretreatment facility.

rebuilding or replacing crucial separation equipment so that more of the raw material arrives in the most desirable products.

For example, a chemical plant purchases soybean oil that escapes being incorporated into the various plastic intermediate products the plant sells. The diluted oil arrives in a tank at the pretreatment facility, where it can be skimmed off the top of the water layer that forms below and stored in totes. For a few years, the plant had a customer who was able to use a product made from the reclaimed oil. Alternatively, the soybean oil could be sold as a feedstock for conversion to diesel fuel. Documenting the volume of reclaimed oil can provide a justification for equipment improvements in the process, such as

54

Check Performance of Unit and Overall Operations Checking the performance of the unit operation before and after the device may be helpful. Sometimes good performance is obvious—for example, before and after the dissolved air flotation (DAF) are quite different with respect to visible oil. However, the sludge press may be making a low solids cake that may be improved by fixing the sludge press. Checking unit operations by analyzing oil/grease concentrations before and after the DAF or the percent (%) solids before and after the sludge press can be worth the cost of analysis.

Activated sludge tanks have two purposes: 1. to convert dissolved organic material into microbial cells, which can be separated from the water; and 2. to convert excess ammonia into nitrite and subsequently nitrate in a process called nitrification. The result is that nitric acid is produced and alkalinity may decrease. the ANALYST Volume 29 Number 2

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continued

multiplying by 60 minutes per hour (m/h) provides the SOUR in milligrams DO per hour per gram of MLSS or MVSS. Results can vary between systems receiving low influent loads of recalcitrant molecules and high concentrations of labile molecules.

Alkalinity can be tested on activated sludge supernatants that are not achieving nitrification goals. (Put a few hundred milliliters in a container and wait for the solids to settle. Use the supernatant as your sample for the alkalinity test.) Calcium carbonate, sodium bicarbonate, calcium hydroxide, or sodium hydroxide are sometimes used to increase alkalinity. Operators of wastewater package plants often carry a bag in their trucks in case the nitric acid produced is impacting metabolism and microbial growth. For pretreatment systems that require supplementation with nitrogen, nitrification may be an indication that less N needs to be supplied.

Table B lists examples of problems that may arise in wastewater pretreatment systems and suggested actions to correct the issue.

Table B: Symptoms, Possible Causes, Possible Remediation Opportunities

Dissolved oxygen (DO). The suggested DO level is 2 to 3 mg/L in the activated sludge. If DO increases and is not related to winter temperatures when the solubility of oxygen increases and metabolism decreases, look for a reason. Here are some areas to consider: Is the food:microorganism (F:M) ratio lower than it was previously?

Was a high-strength waste removed upstream?

Did production decrease?

Symptom

Cause (Example)

Fix

Low pH

Phosphoric acid, beverages

pH adjustment system

High pH

Alkaline waste or cleaners

Review raw materials and cleaning procedures

Foam

Surfactants

Review cleaning procedures

Foam

Bulking bacteria

Waste more, chlorinate RAS temporarily

Foam

Sludge age too long or short

Evaluate influent, effluent BOD

Low DO

Lost raw materials?

Review production

High DO

Production improvements? pH excursions?

Other reasons for decreased metabolism

Decrease air flow Document, follow up Document, follow up

Use Laboratory Resources

Do pH excursions or toxic compounds contribute to potential toxicity?

If DO remains high, it may be time to evaluate energy consumption at the air compressors for potential savings and turning down the air. Cases of increases in DO in the aeration tank have been correlated with stalked protozoans that stopped filtering or protozoans that have formed cysts (resting structures that metabolize slowly or not at all). Cysts are formed when environmental conditions are not appropriate for growth.

Specific Oxygen Uptake Rate (SOUR). SOUR can be used to evaluate microbial population activity. Activated sludge is pre-aerated to oxygen saturation and placed in a BOD bottle with a DO probe. At timed intervals of 30 seconds or 1 minute, the DO is noted, and a plot is made of DO versus time over a period of 15 minutes. Points are plotted and the straight portion of the line is used to calculate the slope, which is the oxygen uptake rate per minute. Dividing by the MLSS or MLVSS in grams and 55

Laboratory resources may include facilities at the pretreatment facility, local commercial or WRRF laboratories, or others able to do additional procedures.

BOD has been used for evaluation of biodegradability by extending the incubation time and monitoring candidate surfactants at candidate concentrations over 30 days instead of the usual 5-day incubation period. Variations using respirometry apparatus are also possible.

Toxicity testing of specific wastes can be evaluated by adding the candidate toxicants at several concentrations to freshly collected activated sludge aliquots in the lab.

Samples are aerated, and aerobic plate counts are done over several timeframes to compare with the untreated control. For labile (unstable and constantly changing) wastes, the treated samples may produce more bacteria than the control, and metabolism may increase if supplemented with additional waste.

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Expand Horizons

If your clients trust you with their chemistry, you may be able to find clues concerning whether a waste is likely to be biodegradable. The “Knowledge Base” biochemistry is a starting point.

Knowledge Base

This summary of the major biological polymers is to provide a framework for thought and discussion.

Carbon, nitrogen, and phosphorous are the most common elements in plants, animals, and microbes.

Sulfur, calcium, magnesium, iron, sodium, potassium, and various metals are needed in lower concentrations.

Carbon is about 50% of the dry weight of cellular material. Nitrogen is about 14% of bacterial cells dry weight, and phosphorous about 3%. Figure 1 shows the structure of lactose.

Figure 1: Structure of lactose, a disaccharide composed of glucose (ring on the right), and galactose (ring on the left).

O

HO

1

R

H

OH

H

H

O

H

R

C

C

N

C

H

OH

H

OH

N H OH

Sugars contain carbon, oxygen, and hydrogen. They may be three, four, five, six, or more carbons with numerous OH groups attached above or below the plane of the ring(s). They can be connected in chains (i.e., polysaccharides). The lactose molecule shown is glucose and galactose connected between the number 4 carbon of the glucose and the first carbon of the galactose. Severing the 1-4 link requires the enzyme lactase, a protein.

People who are lactose intolerant lack this enzyme, and bacteria in the intestine ferment the ingested lactose, producing gas and acid that cause diarrhea.

Sugars are a large and diverse class of biological chemicals. Enzymes specific to the various types of bonds are necessary to break the bonds. Energy stored in the chemical bonds is recovered through the Krebs cycle

56

O

N —C — C

—

H

R

O

N —C — C

α

O

β

OH

Proteins are polymers of 20 different amino acids. The amino group (NH 2) is on one end and the acid (COOH) on the other. Variation is in the R group (Figure 2, left), which may be hydrogen, methyl, alkyl, amino, or ring structures. Amino acids are assembled in chains (polymers) by removing a water molecule from two amino acids. The process is repeated with subsequent coiling and folding of the polymer until large structures, such as muscles or enzymes, are formed.

H

O 4

(citric acid cycle) and some other biochemical pathways some bacteria have. Sugars may also be parts of larger molecules, such as DNA and RNA, where ribose (five carbon) sugars alternated with phosphate form the “sides” of the helical ladder and connect to the purines and pyrimidines that form the “rungs” of the helical ladder.

Figure 2: The figure shows the removal of water from the amino end of one amino acid and the hydroxide OH from the second amino acid to produce a dipeptide.

CH2OH

CH2OH

continued

H

H Peptide Bond

OH

H O C OH

+ H2 O

Lipids (polymers of hydrocarbons) (Figure 3) are associated with the highest energy (calories) or adenosine triphosphate (ATP) per gram. They may be part of glycolipids (sugar-containing lipids), phospholipids, and other molecules that make cell membranes or other structures. Lipids lack nitrogen but are routinely associated with proteins that do contain nitrogen. When body fat is metabolized, an enzyme starts at the COOH end and cuts two carbon segments off, leaving a COOH unit on the end of the chain, which is shorter by two carbons.

The two-carbon piece is further metabolized by the citric acid cycle, the process that generates the intermediates that generate ATP.

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continued

For food and beverage plants, the production waste is routinely biodegradable, and problems are usually associated with a pretreatment system that is overloaded.

Often, production increases with concurrent increases in wastewater but insufficient enlargement of the pretreatment system.

Figure 3: Examples of lipids.

Saturated Fatty Acid

HO

O

H

H

H

H

H

H

H

H

H

H

H

C

C

C

C

C

C

C

C

C

C

C

C

H

H

H

H

H

H

H

H

H

H

H

H

Unsaturated Fatty Acid

HO

H

H

H

H

C

C

C

C

C

H

H

H

H

H

H

H

C

C

O

H

C

H

C

H

H

C

H

H

C

H

H

H

H

H

Figure 4: Possible chemical structure of lignin, the woody part of plants.

OCH3

H2COH HC

H2COH

H3CO

H2COH O

CH

CH HC

HC

O

H3CO

H2COH

O

HC

HC

HC

HC

CO

(OCH3)

O

H3CO

OCH3

HC

15

12

HC 8

CH HCOH

H2COH

6

HC

O

O

HC

HC

7 OH

O

O 19

CH

OH

O

HCOH

OCH3

H2COH

OCH3

CH C

H3CO

O

OH

OCH3

14b

HC

13 b

OCH3

CH

OH

6b

14a

OCH3

H2COH

H2COH OCH3

HCOH

O

11 H3CO

OCH3

CH

HC

OH

CH

CH2

CH2

HC

13a

H2COH O

O

OC

OCH3

HC CH

H3CO

OCH3

HCOH

10

OCH3

OH

HC

O H2C CH

5

H2COH

17

O

O H2COH

9

OCH3

O

H2COH

O

HCO(C6H10O5 )nH

O

HC

18

CH

0.5

OH

4

HC

1/2 H2COH

3

CH

H2COH

O

1/2 HCO

HC

OCH3

H3CO

OH OCH3

1

H2COH

16

2

H2COH CO CH2

OH

HCOH

CO CH2

H2COH

20

H2COH CH CH 14c

O

13c

OCH3

O

OCH3

OCH3

Recalcitrant molecules are resistant to microbial degradation. Proteins and sugars are readily digested and are labile molecules. Cellulose, from which paper is made, is less easily degraded by microbes and requires the enzyme cellulase, which not all microbes produce and people lack. Cellulose consists of polymerized glucose molecules in β 1-4 linkages that, together with some other sugar-based molecules, combine into fibrils and form plant cell walls. Lignin from trees 57

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and woody plants is among the most recalcitrant natural material, and longer degradation times are needed to rot wood. Wood degradation is heavily dependent on various fungi. A schematic of lignin is shown in Figure 4, with numerous phenolic structures and multiple side chains that interconnect.

Of the human-synthesized molecules, some notable recalcitrant molecules have been made, including methyl tertiary butyl ether (MTBE), the gasoline additive that replaced lead for a few years before it was found in groundwater and its use was stopped. Dioxin and various polychlorinated biphenyls (PCBs) were used as insulators for electric grids and are monitored periodically.

Recently, per and polyfluoroalkyl substances (PFAS) used as water repellants and fire suppressants have been found in well waters and are being monitored. The EPA has set Health Advisory Limits (HAL) for some of the PFAS contaminants, and there is the likelihood that regulatory limits will be coming either at the federal, state, or local levels. The ubiquitous recalcitrant molecules are the various plastics that we routinely use once and send to landfills or leave as litter that may subsequently arrive in waterways.

continued

Recalcitrant molecules may be characterized as having substantial branching and cross linking or contain fluorine or chlorine as part of a larger molecule. Other recalcitrant compounds are made of multiple ring structures, including rings with resonance bonding, such as benzene. Notice the various sidechains on the multiple benzene rings in the lignin structure shown in Figure 4, and notice the cross linking.

Microscopy

In the late 1960s and early 1970s, Colin Curds, then curator of zoology at the British Museum of Natural History, sampled about 200 wastewater treatment plants in Great Britain. He was working on computer modeling of ecological succession in the plants after upsets or when newly started. The feature of his work that remains prominent is the Young-Old Sludge Continuum (Figure 5) that can be found in many wastewater manuals. The “sweet spot” when the effluent BOD and total suspended solids (TSS) were lowest was correlated with the presence of the stalked flagellated protozoans. Before and after the stalked protozoans were dominant, the effluent BOD and TSS were higher, with performance of the treatment plant decreased.

Figure 5: The chart derived from Colin Curd’s data with the addition of bacteria on the left, which, together with decaying plant and animal cells, form the basis of the detrital food chain that is the method used at WRRF.

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Relative dominance is the y-axis and time is the x-axis.

As sludge ages or mean cell retention time increases, performance peaks when the stalked ciliates are present, and then amoebae and flagellates are less common. Units are not associated with either axis because systems can be variable. A few days to a few weeks to develop stalked ciliates after an upset in WRRF seems to be the range.

For many pretreatment facilities, protozoans may not be a significant segment of the biota. In those instances, the degradation is accomplished by the bacteria (Figure 6).

continued

Figure 7: Flagellated protozoans are shown in a crystal violet stain of the activated sludge sample.

The following figures are photomicrographs that show different microorganisms associated with wastewater treatment. Figure 6 shows amoeba.

Figure 6: Amoebae extend pseudopods (false feet), which surround food particles and bring them into the single cell for digestion. Pseudopods are also used for locomotion.

In the figure, two flagellates with flagella on both ends of the cells are below the 10 µm marking. Without the dye, the flagellates move too quickly to effectively see the flagella, let alone have two in focus at once. Floc is out of focus on the left, and a few filamentous bacteria are also out of focus. It is “young sludge,” but older than when amoebae predominate.

Figure 8 shows the cilia (microscopic hairs) that cover the bodies of ciliates.

Figure 8: Cilia, microscopic hairs, cover the bodies of the ciliates and are their means of locomotion.

The amoeba is right of the 20 micron (µm) marking and appears to be engulfing a chunk of the bacteria and detritus. A few filamentous bacteria are within the floc and extend from it. Amoebae are indicators of “young sludge.”

Figure 7 shows flagellated protozoans from an activated sludge sample.

The nucleus is the intracellular circle that can be seen in the ciliate above the 10-µm marking. A second ciliate is burrowing in the floc on the right side of the photo. Its movement and a slightly different focal plane make it out of focus. Tightly packed bacteria are somewhat in focus in the top portion of the photo.

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Figure 9 shows stalked ciliates in a colony.

continued

Figure 11: Two nematodes— roundworms (second one is wiggling on the right side).

Figure 9: Stalked ciliates in a colony are embedded in floc.

In the figure, cilia are at the far end of the cell but are retracted and not filtering. During active filtration, the hairs create a current that bring bacteria and small particles into the cell. When stalks are actively filtering, they gradually retract the stalk and spring out in another direction, thus maximizing grazing efficiency. In WRRF plants, having stalked ciliates is considered “ideal sludge.”

Figure 10 is a photomicrograph of a rotifer, such as may be found in old sludge.

Nematodes (Figure 11) have a mouth, esophagus, intestine, and anus. They eat small particles. Note that the floc is poorly formed, and many loose bacteria and particles are floating, which will contribute to high TSS. Nematodes are indicators of “old sludge” at WRRF and wasting sludge is recommended. Effluent will have high TSS. Microorganisms also can harm wastewater treatment operations, as seen in Figure 12.

Figure 12: Filamentous bacteria can cause bulking—the clarifier cannot work because so much of the sludge is floating.

Figure 10: A rotifer is telescoped into itself on the right. It has a ring of cilia that move particles into the body where they are ground up in the mastax, the circular structure about 1/3 down the body.

The two prongs at the bottom end serve as hooks to hold the organism when it stretches out as the partial rotifer in the left corner has done. These organisms are indicators of “old sludge,” and wasting is suggested.

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When this problem occurs, the foam overflows the activated sludge tank, leaving the hapless operators with a mess to clean up. Discharge regulations for TSS and likely other parameters cannot be met. The wastewater the ANALYST Volume 29 Number 2

Practical Tips for Troubleshooting Wastewater Pretreatment Systems

pretreatment plant can suddenly become the most important topic at the manufacturing facility.

continued

Figure 15 shows wastewater effluent with about 200 milligrams per liter (mg/L) of suspended solids, which is acceptable at the large WRRF that accepts the effluent.

Because of the nature of the wastes and flow variations, the ecological succession typical in WRRFs has not occurred in this pretreatment facility. The presence of a few flagellates suggests that this system is running well.

Figure 13 is an example of how filamentous bacteria can also prevent floc from forming.

Figure 13: Portions of two flocs are in the upper left and lower right corners of the photomicrograph.

Figure 15: An example of an industrial pretreatment system with relatively little floc and many bacteria that are loose. A flagellate is above the 20-µm marking.

Filamentous bacteria between the floc can prevent floc from coming close enough together to become one larger floc particle that settles better than pinpoint floc.

Notice the filaments are >300 µm long. Filaments can be springy and occupy significant space. They can also hold air, which results in foam.

Causes of filamentous bacteria include low or high F:M; low or high DO; low nitrogen or phosphorus; and excess fats, oils, and grease. The immediate responses to correct these problems include chlorinating the RAS and wasting sludge. Such action is needed because sludgehauling costs increase quickly, and fines associated with noncompliance with discharge limits may be levied.

Sometimes, microbial filaments may grow in the floc and have a beneficial impact, as seen in Figure 14. The filaments appear to help hold the floc together, resulting in improved settling. A few filaments can also be seen in Figures 6, 7, 9, and 11.

Calculations

The calculations on the following pages are useful when determining if adjustments are needed in the wastewater treatment system.

Figure 14: Some types of filaments grow throughout the floc and extend a relatively short distance from the floc.

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continued

F:M or F/M Food (lb BOD/day) Microorganisms (lb)

=

mg/L BOD influent X influent flow (MGD) X 8.34 lb/gal mg/L MLSS or MLVSS X aeration volume (MGD) X 8.34 lb/gal

Eq. 1

Equation 2 shows the result of calculating the F:M with 2,000 mg/L BOD and 300,000 gallons per day (gpd) influent.

Aeration Volume = 1 MG Solids = 5,000 mg/L MLSS Eq. 2

2,000 X 0.3 MG X 8.34 = 0.12 5,000 X 1 X 8.34

Is this a good or poor result? For pretreatment facilities you cannot tell with only one calculation and no historical information. Assess what the plant is doing: settling, effluent results, performance of unit operations. If discharge requirements are being met, then the calculated F:M is likely in the beneficial range. WRRF often operates with F:M = 0.25 to 0.45. Facilities handling a high-concentration influent operate at lower ratios. Pretreatment facilities may be developing data daily or several times per week using chemical oxygen demand (COD), and a range based on typical flows can be derived. COD includes BOD and inorganics that can be oxidized, but only the BOD is useful to microbes.

C:N:P Ratio For calculating for the Carbon:Nitrogen:Phosphorous (C:N:P) ratio, he recommended ratio is as follows: BOD:NH3:P = 100:5 to 10:1. To determine the ratio, collect samples, run analyses, and then run calculations.

For example: Given: Influent conditions:

BOD = 2,000 mg/L NH3 = 30 mg/L P = 20 mg/L

Divide BOD by whatever factor is needed to make 100 (factor = 20 for this example).

Divide the N and P values by the same factor.

Compare to the idealized range.

2,000/X = 100, so factor for BOD, NH3, P are all 20 30/20 = 1.5 for N 20/20 = 1.0 for P The ratio is 100:1.5:1. Therefore, N is in short supply.

Urea can be purchased and added to a day tank. If high N waste streams are available, they may be useful as a supplement. If a waste stream is considered for use as N supplement, it should be consistently available. It should be checked for organics that are toxic or recalcitrant and metals or other materials that may exceed discharge permits.

Additional sources of phosphorous must be common among the raw materials for chemical plants because P is usually not limiting in many pretreatment systems. In meat, dairy, or other food packing facilities, P is part of the biomolecules being degraded. For some chemical plants, “boil out” cleaning procedures using trisodium phosphate are periodically done.

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Practical Tips for Troubleshooting Wastewater Pretreatment Systems

continued

Hydraulic Retention Time Equation 3 shows how to calculate the Hydraulic Retention Time.

Hydraulic Retention Time = Flow Volume

gpd = gallons

time, usually days

Eq. 3

At a WRRF, hydraulic retention time is frequently one day; it is likely five to 10 days or longer at pretreatment facilities.

Sludge Age Equation 4 shows how to determine the Sludge Age. Sludge Age = Suspended Solids Under Aeration Suspended Solids Added

=

mg/L TSS X tank volume mg/L TSS X gal flow X 8.34 lb/gal

Eq. 4

MLSS = 1,500 mg/L Tank volume = 500,000 gallons = 0.5 MG Flow = 0.5 MGD Incoming TSS from primary clarifier = 200 mg/L 1,500 mg/L X 0.5 MG X 8.34 lb/gal = 200 mg/L X 0.5 MGD X 8.34 lb/gal

6,255 lb = 7.5 days 834 lb/day

Mean Cell Retention Time Sludge age is calculated at the WRRF, since solids leaving the primary clarifier are routinely present. For many pretreatment systems, incoming solids are negligible, which makes the denominator approach zero. The Mean Cell Retention Time (Equation 5) is used for influents with primarily dissolved organic material and little suspended solids.

How to calculate the Mean Cell Retention Time: Aeration Volume = 1,000,000 = 1 MG Flow = 300,000 gpd = 0.3 MGD Mixed Liquor Suspended Solids = 5,000 mg/L MLSS Waste Activated Sludge = WAS = 20,000 gal/day = 0.02 MGD and 9,000 mg/L Effluent TSS = 150 mg/L Mean Cell Retntion Time =

Suspended Solids in Aeration (lb) SS Wasted (lb/day) + SS lost in effluent (lb/day)

5,000 X 1 MG X 8.34 (0.02 X 9,000 mg/L X 8.34 lb/gal) + (0.3 X 150 mg/L X 8.34)

=

Eq. 5

41,700 lb 1,501 lb wasted + 417 lb to effluent

Based on these calculations, the Mean Cell Retention Time = 21.7 days for this example, substantially longer than the five to seven days for WRRF.

Summary

Effective troubleshooting for wastewater pretreatment systems requires the best we are able contribute. It can be an iterative process—pick out the easiest stuff first and go to work on some of the rest, while recognizing that the system will change. The practitioner needs to recognize that the product mix being manufactured, the microbes, 63

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the equipment in use, and the knowledge you need all change.

Wastewater pretreatment facilities associated with manufacturing or food plants may be good opportunities for water treatment professionals to expand their consulting services. Water treatment representatives are already familiar with the plant, the products made, likely raw materials, boiler and cooling water, clean-in-place chemistries, and some of the people who are responsible for maintenance and manufacturing. While work at the pretreatment facility can be straightforward and even obvious (put more raw materials into products and send less to the pretreatment facility), the implementation is not. Surprises will occur because microbial populations are complex and wonderful.

Glossary

Aerobic: Metabolism that uses oxygen; aerobic treatment systems use compressors and diffusers.

Anaerobic: Metabolism that does not use oxygen. In treatment systems, large, stirred tanks are needed.

Organic acids, hydrogen sulfide and methane are common end products.

continued

cBOD: Carbonaceous Biochemical Oxygen Demand is measured in mg/L of oxygen used in five days by the waste sample at 20 º C with the addition of a nitrification inhibitor. This measurement is primarily used for final effluents at WRRF where nitrification is expected.

COD: Chemical Oxygen Demand is a measurement of mg/L oxygen used in two hours under boiling sulfuric acid conditions. COD includes BOD and some inorganics that are oxidized.

DAF: Dissolved Air Flotation is equipment that bubbles air from the bottom of the tank to float oil so that it can be skimmed or decanted.

Floc: The process (as a verb) where small particles in water come together to form larger clumps of particles using coagulating and flocculating chemicals. These clumps, also called floc (the noun), are then more easily removed through settling processes, or less frequently, filtration.

MG: Million gallons MGD: Million gallons per day

Anoxic: Metabolism that uses the oxygen in nitrite and nitrate after the oxygen in a tank has been depleted.

Alkalinity and pH decrease, and alkalinity is sometimes added; the final product is nitrate.

MLSS: Mixed Liquor Suspended Solids (measured in mg/L). A volume of activated sludge is placed on a pre-weighed filter, and water is removed by vacuum filtration. The sample is dried and weighed again.

ATP: Adenosine triphosphate (ATP) is the energy currency of the cell. It is produced when a phosphate is attached to adenosine diphosphate (ADP); the energy is stored in the chemical bond.

MLVSS: Mixed Liquor Volatile Suspended Solids (measured in mg/L), like MLSS with the additional step that the dry filter and sample are burned, and the ash is weighed. Eliminates the inorganics in the activated sludge and measures organisms and particulate organics.

Bulking: Filamentous bacteria that float, preventing effective separation of water and solids, particularly for WRRF; frequently observed in systems with reverse osmosis (RO) membranes where the detrimental effect is less than it is in clarifiers. See photographs in “Wastewater Microbes” section of this article.

Nitrification: The aerobic biological process that converts ammonia to nitrite then nitrate.

Package plant: Small facilities associated with restaurants, churches, golf courses, or other buildings that are remote from a sewer system. The volume and concentration of the waste is too large to be handled with a septic system or the tank systems associated with houses not on a sewer system.

BOD: Biochemical Oxygen Demand is measured in mg/L of oxygen used in five days at 20 º C by the waste sample when all the non-carbon nutrients and appropriate pH are provided.

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Practical Tips for Troubleshooting Wastewater Pretreatment Systems

Pretreatment facility: Wastewater treatment plants typically owned and operated by a manufacturing facility.

They usually discharge to a WRRF but may have a permit to discharge to a waterway such as a ditch or stream.

RAS: Return Activated Sludge leaves the clarifier and returns to the activated sludge tank. This returned sludge is crucial to keeping the microbes in the tank long enough to grow to large numbers and a diverse population.

continued

Kerri, K.D.; Dendy, B.B.; Brady, J.; Crooks, W. (1993). Operation of Wastewater Treatment Plants, vol. 2, Hornet Foundation, Inc., California State University, Sacramento, California Meitz, A. (1997). “Wastewater Microbes. A Photographic Catalog,” 12-page brochure.

Michigan Department of Environmental Quality (2017). “Activated Sludge Process Control: Training Manual for Wastewater Treatment Plant Operators,” Michigan Department of Environmental Quality, Lansing, Michigan, https://www.michigan.gov/documents/deq/wrd-ot-activated-sludge-manual_460007_7.pdf.

Ohio EPA (November 2014). “Activated Sludge Process Control and Troubleshooting Chart,” Compliance Assistance Unit, Ohio Environmental Protection Agency, Columbus, Ohio, https://www.epa.ohio.gov/Portals/29/ documents/CAU/Activated%20Sludge%20Process%20Control%20and%20 Troubleshooting%20Manual.pdf.

Rawn, J.D. (1989). Biochemistry, Carolina Biological Supply Co., Burlington, North Carolina, ISBN 0-89278-400-8.

TSS: Commonly a laboratory test that filters a known volume of water through a specified preweighed filter, dries the filter at 105 °C, and weighs the filter after drying. Results are expressed as mg/L TSS.

Reddy, C.A.; Forney, L. (1978). Lignin Chemistry and Structure in Developments in Industrial Microbiology, vol. 19:27-34, Society for Industrial Microbiology, Arlington, Virginia, Library of Congress # 60-13953.

Santa Rosa Junior College Staff (n.d.). “Specific Oxygen Uptake Rate (SOUR),” Santa Rosa Junior College, Santa Rosa, California, http://srjcstaff. santarosa.edu/~oraola/sour.html.

WRRF: Water Resource Recovery Facility. Former names were sewage treatment plant, wastewater treatment plant, or publicly operated treatment works.

WAS: Waste Activated Sludge leaves the clarifier and is removed from the system.

Bibliography Curds, C.R. (1971). “Computer Simulations of Microbial Population Dynamics in the Activated-Sludge Process,” Water Research, 5, pp. 1049-1066.

Curds, C.R. (1992). Protozoa in the Water Industry, Cambridge University Press, Oxford, England, ISBN 0 521 39731 6.

EPA ( January 2001). “Method 1683: Specific Oxygen Uptake Rate in Biosolids,” draft document, EPA-821-R-01-014, https://www.epa.gov/sites/ default/files/2015-10/documents/method_1683_draft_2001.pdf.

Amanda Meitz is the owner of Biosolutions LLC, a water-testing laboratory that provides chemical (metals, ion chromatography, and some wet chemistry) and microbial analysis of potable, process, and wastewaters and deposits associated with process or wastewater. She has an M.S. in microbiology from Michigan State University and was previously employed at Nalco Diversified Technologies and predecessor companies. Ms. Meitz may be contacted at amanda@biosolutionslab.com.

This article is based on a paper presented by the author at the 2021 AWT Annual Conference, which was conducted September 22–25, 2021, in Providence, Rhode Island.

Jenkins, D.; Richard, M.G.; Daigger, G.T. (2004). Manual on the Causes and Control of Activated Sludge Bulking, Foaming, and Other Solids Separation Problems, 3rd ed., Lewis Publishers, Boca Raton, Florida, ISBN 1-84339046-9.

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Industry Notes Sam Rivera Joins ResinTech Filterworks Sales Team Ion exchange manufacturer ResinTech announced that Sam Rivera joined the technical sales team for the company's Filterworks division (formerly Aries Filterworks) as the Southeastern sales manager for lab system and OEM sales.

H2O Janet Stout and fellow researchers launched Special Pathogens Laboratory. Since its inception in 2007, the company has continued the work of preventing outbreaks and advancing research to end Legionnaires’ disease.

H2SO4

Rivera, a 30-year industry veteran, has held various sales and product development roles at Millipore Sigma, Kinetico, Culligan, and Med Water.

“Special Pathogens Laboratory sets the industry standard for Legionella control and prevention,” states Pace® CEO Eric Roman. “We look forward to welcoming Special Pathogens Laboratory and its highly qualified and dedicated team to Pace®. This acquisition reinforces our commitment to provide testing and analytical solutions to protect our environment and improve our health.”

"Having implemented high-purity water systems in some of the world's most sophisticated and demanding environments, Sam's credibility in the laboratory water market and his business development track record make him ideally suited to expand our business in the Southeastern U.S. We are all delighted he has chosen to join ResinTech," said Filterworks division president Frank Firicano.

Special Pathogens Laboratory provides healthcare, water treatment industries, hotels, and commercial and industrial sectors with a comprehensive solution for the prevention and control of Legionella. “Combining a consultative approach with lab services, risk assessment, response management, and proprietary software technology, Special Pathogens Laboratory offers customers an integrated platform of evidence-based solutions for outbreak prevention and liability mitigation,” states the president of Pace® Analytical Services, Greg Whitman.

“The dedication of the team at Special Pathogens to this disease is in complete alignment with the commitment of Pace® to provide solutions to protect the health and safety of our communities and lives.”

Rivera holds a B.S. in biology and microbiology from Sacred Heart University and will report to national lab and OEM sales manager Jon Bergman.

The addition of Rivera comes at a pivotal time for ResinTech, having opened a new $138.8 million ion-exchange factory in the United States in 2020. ResinTech is now the world's only water system manufacturer that makes every component of its water systems—filtration media, filter cartridges, and system hardware.

Acquisition Expands Pace® Presence for Legionella Testing and Analytical Services Pace® Analytical Services, a division of Pace® Science and Technology Company and a preferred provider of in-lab, mobile, and emergency onsite specialty-contaminant and regulatory testing and analysis services, announced that it has acquired Special Pathogens Laboratory, a market leader in Legionella testing, detection, remediation, and prevention.

Special Pathogens Laboratory is transitioning to operating under the Pace® brand. Special Pathogens Laboratory has locations in Pittsburgh and New York City and supports customers across the United States.

AquaPhoenix Named One of the Top 50 Fastest Growing Companies for 2021 AquaPhoenix has been named as one of the “Top 50 Fastest Growing Companies” in Central Penn Business Journal.

After successfully controlling Legionella at the Veteran’s Healthcare Administration for more than 25 years, Dr. 67

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Industry Notes continued

AquaPhoenix Breaks Ground on Corporate Headquarters Expansion As part of its community commitment and dedication to continuous improvement, AquaPhoenix officially broke ground on an expansion of its corporate headquarters.

The project will add a further 90,000 square feet of warehousing and manufacturing facilities to the existing 200,000 square feet footprint.

Central Penn Business Journal’s “Top 50 Fastest Growing Companies” is an annual list designed to recognize the top regional businesses in Central Pennsylvania by revenue growth. To qualify for the 2021 list, companies were required to show revenue growth over three years ending with fiscal year 2020.

“It is an honor to have been recognized by CPBJ as one of the Fastest Growing Companies. AquaPhoenix has achieved strong growth since its inception in 2003, and this award reflects the tireless efforts and commitment of everyone at the company,” said Frank Lecrone, CEO of AquaPhoenix.

AquaPhoenix was previously named to the list in 2017, 2013, 2012, and 2010.

AquaPhoenix Scientific Acquires AMT Scientific AquaPhoenix Scientific LLC announced that the company finalized an asset purchase agreement with AMT Scientific LLC (Baltimore, Maryland), a manufacturer of biological and chemical water analysis glass ampoule test kits.

"Through our years of incredible growth, we've called Hanover home, so to be able to expand our headquarters in my hometown, is important," said Frank Lecrone, CEO. "We never imagined outgrowing the warehouse when we moved into this new space in 2017, and five years on, I don't expect the new expansion to be vacant for long."

"It's been a challenge to meet the needs of our growing business with our existing space," added Henry Bushinski, vice president. "This investment in our corporate headquarters allows us to better plan for the future and increase efficiency. It will give us more room to grow and fix storage-related issues."

As part of the agreement, AquaPhoenix will integrate AMT’s suite of water analysis glass ampoules into its current portfolio to further strengthen the company’s position in the industrial marketplace.

“We are excited to incorporate AMT’s products into our Hanover manufacturing facility. This acquisition represents our continued focus on strengthening our product offering to remain a trusted and reliable supplier to our customers,” said Frank Lecrone, CEO of AquaPhoenix.

Construction is officially underway on the warehouse expansion project for AquaPhoenix headquarters and is set for completion by the end of 2022. AquaPhoenix has once again partnered with Conewago Enterprises to complete this project. Conewago constructed our two-story office and renovated our modern, climate-controlled warehouse in 2016. We can't wait to give you a tour.

AMT Scientific is a full-service scientific and industrial developer and manufacturer of water analysis test kits. The test kits use a self-filling reagent ampoule, with simple “snap” and easy result interpretations based on visual color change.

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Discovering AWT

Welcome to our new column that will highlight different AWT members. The aim of this ongoing column is to help introduce readers to the different companies that make up AWT.

Advantage Controls

4700 Harold Abitz Drive Muskogee, OK (800) 743-7431 www.AdvantageControls.com

Company History Following the sale of his previous water treatment equipment company, Morr Control, Dick Morris founded Advantage Controls with his son, Chris, in 1994. From the first beginnings in a 900-square-foot rented space in a small downtown office building, the company has expanded seven times to its current 52,000-square-feet of manufacturing, engineering, and warehouse space across a multi-building campus. Advantage Controls entered the reverse osmosis market in 2020 with the acquisition of the R&D Specialties line of RO controllers.

Current Business Locations Advantage Controls’ home office is located in Muskogee, Oklahoma, while the firm also has 11 regional offices spread across the United States.

Current Business Advantage Controls manufactures control and chemical metering systems for commercial and industrial water treatment. Controller offerings for the cooling tower/ boiler market range from a line of two-relay chemical feed timers to cloud-capable touchscreen controllers with up to 20 relays, 32 sensor/analog inputs, and 42 digital inputs. The Advantage Controls metering pump line includes options for both manual output adjustment and built-in timer controls used in water treatment and oil field applications. In addition to its core controller and pump offerings, the company manufactures a full line of complimentary accessory items designed to complete any water treatment system installation. These accessories include bypass feeders, glycol feeders, corrosion coupon racks, turn-key prefabricated systems, and others.

Advantage Controls has 11 regional sales offices across the United States and regional distribution partnerships in five international countries with installations in more than 70 countries.

Top Executives Dick Morris, Founder; Dan Morris, CEO; Jeff O’Neal, President; Greg Powell, VP of Technology; and Jon Shaw, National Sales Manager.

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AWT Membership The firm joined AWT in 1994.

AWT Awards Advantage Controls was recognized as the 2006 AWT Supplier of the Year.

Advantage Controls' manufacturing plant in Muskogee, Oklahoma.

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Discovering AWT continued

QualiChem, Inc.

2003 Salem Industrial Drive Salem, VA 24153 (540) 375-6700 www.qualichem.com

Company History QualiChem was founded in 1989 as a manufacturer of blended water treatment products for regional water treatment service companies throughout the Southeast. Over the past 33 years, the company has expanded to include metalworking fluids and water treatment chemicals sold globally. The Water Treatment Division has grown to support regional water treatment service companies both nationally and throughout the world.

AWT Membership The company has been an AWT member for 15 years.

Current Business QualiChem currently operates as two divisions, supplying products to different market segments.

As an ISO 9001:2015 certified company, the firm's Metalworking Division sells QualiChem branded products through distribution; the Water Treatment Division continues with its strong heritage of a No Direct Sales approach with private label water treatment products only and strong technical support from multiple CWTs on staff.

Inside a QualiChem manufacturing plant.

AWT Awards QualiChem was recognized as the 2016 Supplier of the Year.

Top Executives Tim Davis, President; Doug Frassa, Executive Vice President.

QualiChem has more than 100 employees who work in three manufacturing locations, a distribution center, and research center. The Water Treatment Division manufactures scale and corrosion inhibitors as well as other products for boiler, cooling, and other water treatment applications. It also offers registered biocides as part of the portfolio.

Business Locations QualiChem supports customers globally through two manufacturing plants and a distribution center and research center in Salem, Virginia, and a third manufacturing plant in Verdi, Nevada.

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WaterColor Management 251 Johnston Street, SE, Suite 404 Decatur, Alabama 35601 (256) 260 0412 www.watercolormanagement.com

Company History WaterColor Management was founded the same year as AWT—in 1986. WaterColor’s purpose is to procure insurance for AWT members. Insurance was unavailable for chemical risk exposures in the mid-to-late 1980s.

WaterColor and the original AWT members formed their own insurance company, Water Treaters Industry Assurance, Ltd. As a result, members were able to produce Certificates of Insurance for their customers and therefore to continue in business. In 2010, the insurance company was replaced by WaterColor’s AM Best A-Rated U.S. program. A Canadian AWT member insurance program followed in 2020.

Current Business WaterColor offers water-treatment-focused AM Best A-rated insurance for water treaters, suppliers, and water chemical blenders and distributors. Coverage features include General, Professional, Products, Completed Operations, Pollution, and Umbrella Liability insurance.

Legionella, viruses, and other types of waterborne pathogens and mold are covered. Blanket additional insured, primary, and noncontributory and waivers of subrogation endorsements are included in the program. WaterColor also offers Commercial Auto, Property, Inland Marine, Cyber, Ransomware, and Workers Comp policies nationally. Loss control survey reports are included in premiums, as are self-service certificates of insurance on the WaterColor app. Claims defense is supported by attorneys, laboratories, and engineers who specialize in water treatment. The company itself underwrites insurance coverages throughout the continental United States and Canada.

AWT Membership WaterColor was a founding member of AWT in 1986.

The AWT’s original raison d’etre was the procurement of insurance, which was unavailable for chemical-related businesses in the mid-to-late 1980s.

AWT Awards WaterColor Management received AWT’s 2007 Supplier of the Year Award.

Top Executives Don Cleveland, President and Chief Underwriting Officer; Kristn Click, Vice President and Controller; Karen Seals, Assistant Vice President and Senior Underwriter; Rhonda Flaherty, Underwriter; Joe Raines, Underwriter; and John Walsh, Director.

Members of WaterColor’s management team: (left to right) Standing—Don Cleveland, Rhonda Flaherty, Elena Peredkova, Joe Raines; Seated—Karen Seals, John Walsh, and Kristn Click.

Business Locations Decatur, Alabama; Delray Beach, Florida; and Houston, Texas.

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Amplify AWT

YOUR VOICE HONORS OUR LEGACY.

Vote in September

In September 2021, AWT began a conversation with the membership around two proposed bylaw changes that are designed to enrich the community as well as grow the organization. Two measures were presented to the membership at the annual meeting by a task force that spent several months refining and revising changes that would be in the best interest of the membership. After further discussions, including online town halls, the Board approved the task force proposed language at its Q1 2022 meeting.

The vote on the following two ballot measures will take place at the membership meeting this September.

Important: You do not need to be physically present in Vancouver to vote. The meeting will be livestreamed, and AWT has created a way for any eligible member to vote, regardless of their participation at the convention.

Details for how this will work will be sent to eligible voting members this summer.

Current 2.2. Eligibility.

The qualifications for each membership class shall be as follows: 2.2.1. Water Treatment Company (WTC). Companies whose primary customer is the water treatment end-user (80% of sales to end-user). The company is limited to annual gross sales of $100 million U.S. from water treatment operations. This category can include divisions and subsidiaries of larger companies only if the parent company is not involved in the sale of water treatment products or components. If two subsidiaries or divisions join, their combined total annual gross sales must be under $100M US from water treatment operations.

Proposed 2.2. Eligibility.

The qualifications for each membership class shall be as follows:

Proposed Measure 1

2.2.1. Water Treatment Company (WTC). Companies whose primary customer is the water treatment end-user (80% of sales to end-user). The company is limited no more than 500 full-time employees working in the water treatment division to qualify for this category. This category can include divisions and subsidiaries of larger companies only if the parent company is not involved in the sale of water treatment products or components.

If two subsidiaries or divisions join, they shall not have more than 500 full-time employees.

To increase the cap for membership to 500 or fewer employees in a water treatment division.

The following changes will be put forth as one motion regarding Measure 1 only. Proposed Measure 2 is listed separately.

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Amplify AWT continued

Current 2.1. Classes.

There shall be six classes of members: Water Treatment Company (WTC); Water Treatment Supplier Company (WTS); Honorary Emeritus; Sustaining; and Student.

A second section of the bylaws would also need to be modified to align with this change: Current 2.2.8. Prohibited Organization. Any Water Treatment Company (WTC) that has, in the aggregate, more than one hundred fifty (150) full time employees in the water treatment division or that is greater than $100M US. Sustaining Members are exempt from this provision.

Proposed 2.2.8. Prohibited Organization. Any Water Treatment Company (WTC) that has, in the aggregate, more than five hundred (500) full-time employees in the water treatment division. Sustaining members are exempt from this provision.

Rationale According to the SBA categorization for our type of business, a “small business” is 500 employees or fewer, so it would follow an existing precedent. With the cap set at 500 employees, we serve our historical desire to remain small business focused.

It has been almost two decades since the size restriction has been modified, which has not allowed for inflation. By setting the increase higher than just the inflation rate, we can account for growth into the future.

Members would not be punished/excluded for growing.

Historically, excluding members who have grown has resulted in a loss of talent, intellectual capital, and contributions for the good of the members. Members who have had to leave committee participation because their company sized out would be able to return.

Proposed 2.1. Classes.

There shall be six classes of members: Water Treatment Company (WTC); Water Treatment Supplier Company (WTS); Honorary Emeritus; Sustaining; Individual and Student.

A second section of the bylaws would also need to be modified to align with this change. For this addition, there is no modification to existing language since it is new proposed language.

Current – Not Applicable Section 2.2 of the AWT bylaws outlines the eligibility of all classes of membership as listed in Section 2.1

Proposed The addition of the following category and updated numbering of subsequent categories: 2.2.5. Individual. Anyone with an interest in water treatment.

2.2.6. Student. Students that qualify under the SEED program description as prescribed by the policies and procedures as set by the board of directors.

2.2.7 Common Ownership. Any eligible member company with common ownership or control by a current AWT member company may elect to join AWT. If the eligible member companies share the same membership category, one of the companies would be required to sub-register under that membership category.

If the companies qualify for different categories, they would join at the WTC membership rates. Companies are in the WTC category, and still meet the criteria for a WTC, then the owner must designate which company will be the voting member. Member companies with common ownership or control may only have one representative elected to the Board of Directors at any given time.

We would allow for growth and increased member engagement, all while remaining true to the spirit of helping small business owners.

Proposed Measure 2

The addition of an individual membership category.

The following changes will be proposed as one measure, separate from Measure 1.

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Amplify AWT continued

2.2.8 Prohibited Organization. Any Water Treatment Company (WTC) that has, in the aggregate, more than one hundred fifty (150) full-time employees in the water treatment division or annual gross revenues from a primary water treatment operation that is greater than $30M US. Sustaining Members are exempt from this provision.

3. Chairing any AWT committee

Rationale AWT small business owners would gain access to a wider network both domestically and abroad. New participants and their participation would enrich the value of the AWT community. There are many talented individuals who could contribute to the talent pool, and thereby increase our collective intellectual capital.

Individual membership would help AWT gain a greater international footprint.

1. Access to member educational resources

4. Participating in all “business owner only” functions, including the business resources section of the website.

They would get:

2. Member pricing for all events 3. Ability to participate in committees, but not chair 4. Greater connection to our community, but not any decision-making control To view all FAQs on these ballot measures as well as learn more about the voting process, please visit https:// www.awt.org/members-section/amplify-awt.

This category would be restricted from: 1. Voting in AWT elections.

2. Sitting on the board of directors

Uniphos 2020.pdf 1 4/23/2020 3:57:49 PM

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A US-based company helping North American water treatment chemical companies, blenders, and distributors.

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Uniphos, Inc.

1011 West Lake Street Suite 210 Oak Park, IL 60301

Phone: 708 445-1294 • Fax: 708 445-1394 • Email: gcollias.uniphos@sbcglobal.net

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CWT Spotlight

John Sandford SMS Environmental Ltd Aylesbury, Buckinghamshire, United Kingdom

What prompted you to obtain your CWT, and when did you begin the process by taking the test?

I joined the industry in 1990 when I was hired by a certain Colin Frayne, CWT. Colin was my first boss and mentor, but over the years we had lost touch. Then, in autumn 2020, I was fortunate enough to be elected onto the Water Management Society’s (WMSoc) Council.

WMSoc are equivalent to the AWT here in the UK. Following the election I had a biography written in Waterline, which is WMSoc’s quarterly magazine. Colin saw the article and we got back in touch, but being the nosey bloke I am, I did an internet search on Colin and came across the excellent Scaling Up! H2O podcast with Trace Blackmore where he interviewed Colin (Episodes 101 & 102). During the interview, Colin discussed AWT and how important the CWT credential was. I think when Trace questioned him on it, he laid out just what made the CWT so good and why it was crucial to the industry.

I subscribed to Scaling Up! H20 and then listened to episode 026, the one that’s all about the CWT, with Angela Pike from AWT. Now in the UK, despite the best efforts from some very good organisations, there is nothing like the CWT, so after listening to episode 026, I decided I had to get my CWT. So I joined the AWT and signed up for the CWT in early 2021 and actually took the test at a Pearson Vue center in a town called Aylesbury Buckinghamshire here in the UK on 21 October 2021.

Exchange, and an archive of the Analyst going back to 1988—an invaluable resource.

Secondly, actually book the exam. You can book it up to a year ahead, but I know I needed it in the diary, so that gave me a deadline, which in turn forced me to schedule enough time for revision.

What was the most difficult aspect of the exam?

Time management during the exam isn't difficult exactly, but it needs thought before you go in, and I would have a plan. In the past, if I finished an exam early, I would just up and leave. But on this occasion, I used the excellent tool of being able to mark a question you are unsure of and revisit it later. Remember, there are 200 questions, so it really was useful. Other than that, I think in my case it was fear. The fear of not passing the exam was also something I found difficult. A lot of people knew I was taking it (because I have a big mouth) and I worried they would feel less of me had I failed—remember, I had been in the industry for 30 years. But actually, that fear became a driver in the end, and I just consoled myself that anything worth having is difficult, and there is always risk of failure in anything we do. After being through the process, I don’t think any less of anyone who has taken the test and not gotten through. At least they stood up to the plate, and that to me is admirable.

How did you prepare for the test?

The first thing I did was actually book the exam so that I had a deadline. Then I scheduled revision in my diary.

Now, for me, I did that every day I worked on the “little and often” principle, but with an increase in time as the exam approached. I worked through all of the online papers and training on the AWT website, and I got a copy of the AWT Technical Reference & Training Manual (this was for reference really, and for clarifying points I was unsure of). I spend a lot of time in the car, so I also

What advice would you give those thinking about taking the exam?

Become a member of AWT if you can. Until you are a member, you just don’t appreciate what an amazing educational resource it is. Much of its online training is free, and in addition, it has technical papers, the AWT

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CWT Spotlight continued

How has your CWT improved your professional career?

However experienced and knowledgeable you may be, just going through the process of obtaining your CWT will improve and consolidate your knowledge. In addition, it does open up opportunities.

subscribed to Trace Blackmore's Scaling Up! H2O—the Pinks and Blues episodes especially are excellent.

One tip I would give is if you are taking the exam at a Pearson Vue center, make sure you read the instructions that they send you properly (I thought I had but I hadn’t). They are quite rightly very diligent about things like ID, etc., and when you turn up, you are provided with a locker and have to put everything other than your photo ID in a locker. I showed up in a hoodie on a cold October day to be told it was a banned item—I think it’s because you can pull the hood up to hide your face. Anyway ,I did the whole four hours with my teeth chattering

Why do you feel this credential was important to have?

I am really clear on this: For me, the most important reason to have the CWT is recognition from your peers.

I love our industry, but we have all seen examples of poor practice, lack of knowledge, and so on. So it is great to have a credential that means I am a credible practitioner, and this is recognised not only by clients but more importantly, by my peers.

What are the advantages of having the CWT designation?

The CWT designation is objective proof that you have the necessary knowledge, experience, and training to be a professional water treater. This is a real benefit and definite advantage over individuals who may have all the relevant knowledge but don’t hold the designation.

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What do you think are the most prominent issues facing the water industry today?

I am going to sound like an old codger now talking about the good old days, but back in the days of Nalco and Dearborn and Betz and Drew, before all the big mergers and so on, they all had big training programs that produced excellent water treatment professionals.

And although I never worked for any of the big boys, I worked at companies that were led by individuals who had come from them, and they had adopted those training regimes.

In the UK, the Legionella business is disproportionately big now because there are laws and legal duties placed on organisations that must comply with them. Hence, we have a lot of people who can tell you about Legionella but not enough who know about steam boilers, proper water treatment, closed loops, wastewater, and the like.

We have a real knowledge and skills gap. This is actually why I was so drawn to the CWT. It applies the same discipline, rigorous training, and expectations to the individuals that hold the credential as those old training programmes, and in my opinion, this is why the CWT is not only important, but it’s actually crucial to the future well-being of our industry.

the ANALYST Volume 29 Number 2

Making a Splash

Adam Sites, CWT CTI Water Treatment McKeesport, Pennsylvania

What prompted you to start volunteering with AWT? There were actually a number of factors that all came together and prompted me to start volunteering with AWT. After I earned my CWT, I realized that I had just done a lot of work on myself as a water treater, but there was still more work to be done to continue to broaden my knowledge. I also realized that maybe there was a slim chance that I could contribute back to the organization that was recognizing my accomplishments. There are plenty of champions in our industry that I would hear telling stories of the lasting relationships and the ability to both contribute and benefit from involvement in the organization, so I started looking at the volunteer opportunities available to me. Around the same time, I acquired a new client that was utilizing a dealkalizer, and although I knew enough about what it was supposed to do, I did not have enough hands-on experience to totally get it. It became apparent to me that the Pretreatment Subcommittee might be able to satisfy my new need for specific knowledge and position myself to become more involved in AWT and the water treatment community.

on the road and in customer locations working independently from other water treatment professionals amid the expectation that we have all the answers to whatever problem is presented. Pulling on different strengths and perspectives within the committee has helped show me that it’s okay to not have the answer and turn to those that do. Putting our ideas together can result in some really great results. I have seen this play out in my career as I run into issues that I am unfamiliar with and take time to ask questions and get valuable input from my clients, peers, and other experts.

What has been the most rewarding thing about volunteering?

For me it has been the ability to connect with my peers with whom I normally would not have the chance. There are discussions about projects that we are working on as a team, but there is time spent getting to know each other as individuals as well. When going to an AWT training or convention, I now see people that I have spent time with throughout the year, and it makes one feel part of something bigger. Also, there is no doubt that by volunteering, you are able to stay on Angela’s good side.

How has volunteering improved your professional career?

Volunteering with AWT has helped me become better at working within a team. Water treaters are typically out 77

Why would you encourage others to become a volunteer?

AWT offers so many resources to the membership.

Those resources do not just mysteriously appear. There is a lot of work put in by individuals to keep the benefits of AWT current and relevant to the constantly evolving needs of the water treatment community. With more volunteers to spread the workload around, there is more opportunity to improve upon offerings and take on new projects. I’m not trying to say that the people that contributed have given all that they can give, as that is far from the case. But new and fresh ideas are so crucial to the success of any organization. Looking at some of the newer offerings in the members only section of the website, I see individuals I was totally unfamiliar with 10–15 years ago. But now they are the new faces within the industry who are becoming more recognizable for being active and for being leaders. Volunteering seems to be such an easy way to put yourself in position to either be that influential person yourself or surround yourself with others who are.

What advice would you give someone thinking about becoming a volunteer?

You hear all the time that the more you put into something, the more you get out of it. This is so true.

Reflecting on my own path of volunteering, I can see the ANALYST Volume 29 Number 2

Making a Splash continued

what the Learning Lounge for pretreatment looks like at the AWT convention. The Learning Lounges have been a way for subcommittees to present ideas that they are currently working on and some informal open discussions about specific areas of interest. The Pretreatment Subcommittee is looking to continue that concept but to incorporate a hands-on approach as well. We would like to give the membership an opportunity to see components of pretreatment equipment in action and be able to ask questions about that. This can also serve as an invitation to attend those sessions if your schedule permits.

that clearly. When I first began volunteering, I would merely join the call and not really have much to say or contribute. I was probably intimidated to do so and waiting for some invitation to jump in. To be honest, I would leave those calls and think I could be doing something else with my time. It occurred to me that I was not pouring into the committee and remembering why I got involved in the first place. I made the decision to get over myself and not just join the call, but join the discussion. At this time, I am a voice in the room and feel really good about what I can offer and take away from the meetings. I would encourage someone getting involved to first, do what is comfortable for you, but also to stretch that comfort zone and you will be welcomed. Although there are quite a few committees and everyone is clamoring for new membership, the Young Professionals Group is probably a great place to get started and see what path you can take from there … but feel free to join more than one if you like.

What is a past project that your committee produced that you feel has had the greatest impact on AWT and why?

Within the pretreatment section of the AWT website there are some extremely helpful guides to water softener calculations, RO calculations, and dealkalizer calculations. I had been using those spreadsheets/documents well before joining the committee and find them to be such a useful tool. This is something that really any level of experienced water treater can use in a practical way. Knowing how to understand inputs, functions, and outputs of the equipment we are tasked with servicing provides such a value to our clients that I would encourage anyone reading this to check out these documents or really the whole AWT collection of resources.

There are so many ways we can apply the information provided for us to everyday use. For that, I would like to thank my predecessors for all their contributions.

Tell us about a current project you or your committee is working on?

The Pretreatment Subcommittee is currently in the process of taking on a few different projects. We have seen the incredible efforts put forth by some people in the new troubleshooting video series. Our goal is to pull some areas of our focus and create troubleshooting videos to accompany the existing collection. First up on our radar are water softeners and a basic field service guide to troubleshooting some common problems.

Another project we are working on is re-envisioning

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the ANALYST Volume 29 Number 2

Capital Eyes

EPA Proposing to Revamp Clean Water Act Discharge Regulations The Environmental Protection Agency (EPA) is proposing to require planning for worst-case discharges of Clean Water Act (CWA) hazardous substances for onshore non-transportation-related facilities that could reasonably be expected to cause substantial harm to the environment by discharging CWA hazardous substances into or on the navigable waters. The CWA states that regulations shall be issued that require an owner or operator of a facility to prepare and submit a plan for responding, to the maximum extent practicable, to a worst-case discharge and to a substantial threat of such a discharge of a hazardous substance. Among the entities potentially affect by this proposed rule are chemical manufacturers.

Overall, EPA is proposing a regulatory program whereby those facilities that could reasonably be expected to cause substantial harm to the environment are required to prepare and submit a CWA hazardous substance Facility Response Plan (FRP) to the EPA for worst-case discharges.

While the proposed rule covers a lot of areas, below are some of the more important changes that could impact water treatment facilities and their customers.

Screening of Facilities. EPA is proposing two initial screening criteria to determine whether a facility, because of its location, could cause substantial harm to the environment from a worst-case discharge. The first step is to determine whether a facility has the container capacity for a CWA hazardous substance on site at or above a threshold quantity. If so, the facility owner or operator then determines whether the facility is within one-half mile to navigable water or a conveyance to navigable water. If those two conditions are satisfied, the owner or operator determines whether the facility meets any of the four substantial harm criteria: the ability to adversely

impact a public water system; the ability to cause injury to fish, wildlife, and sensitive environments; the ability to cause injury to public receptors; and/or having had a reportable discharge within the last five years. If any of those criteria are met, then the owner or operator must submit a CWA hazardous substance FRP to EPA. Staff Contact. EPA proposes that FRPs must identify the qualified individual having full authority to implement response actions and require immediate communications between that individual and the appropriate federal official and the persons providing personnel and equipment, with a description of duties and responsibilities. The plan must also identify and ensure by contract or other approved means, the availability of private personnel and equipment necessary to respond to a worst-case discharge to the maximum extent practicable.

Maximum Capacity On Site. EPA is proposing to define maximum capacity on site as the total aggregate container capacity of each CWA hazardous substance present at all locations within the entire facility at any given time. EPA recognizes that for the chemical industry, chemical inventory quantities routinely fluctuate, and facilities use a wide variety of containers to store CWA hazardous substances. Thus, the EPA believes that regulating facilities based on the maximum container capacity on site will allow regulated stakeholders an opportunity to plan for the worst-case quantities of CWA hazardous substances at the facility.

Worst-Case Scenarios. EPA is proposing to require facilities to develop one worst-case discharge scenario for the container with the largest capacity of a CWA hazardous substance with a maximum capacity on site that meets or exceeds the threshold quantity in one container or group of interconnected containers. This would capture the worst-case discharge at the facility for continued on page 82

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Tales From the Waterside

Discovering Reasons for a Refinery Cooling Tower’s Severe Corrosion and Fouling Problems Bob Cunningham, International Water Consulting, Inc.

A large Western U.S. oil refinery had successfully operated four cooling tower systems for many years. The refinery had successfully transitioned 15 years earlier from a typical chrome-zinc cooling water treatment program employing chlorine for microbial control, supplemented with occasional use of nonoxidizers, and sulfuric acid for pH control.

The treatment program currently in use involved a combination of inorganic phosphate; polymer for deposit control; 2-phosphonobutane-1,2,4-tricarboxylic acid; and yellow metal inhibitor. pH control was accomplished with sulfuric acid, and microbial control employed either chlorine or bromine, supplemented periodically with isothiazolin on a slug feed basis. The plant had been using smart chemical feed and control systems using fluorescent control of inhibitor feeds, pH control for acid addition, conductivity for cycle control, and manual testing for control of oxidizing microbicide.

Oxidation reduction potential was also continuously monitored. The nonoxidizer was fed based on system volume. The smart controller was supplemented with routine manual control tests.

The vendor had just replaced its highly experienced service team with another highly experienced team from a different part of the country, but the new team, although good, was still learning the peculiarities of this refinery.

The Cooling System

The #1 Crude Unit Cooling Tower was a complex system with process exchangers incorporated from a variety of severe duty processes with multiple metallurgies. It operated relatively well, despite flow problems associated with hot overhead bundles and some flow problems

elsewhere due to pinching of flow because of process temperature requirements. This cooling tower operated at a 22,000-gallons-per-minute recirculation rate, with a system volume of roughly 105,000 gallons. The tower was a Marley crossflow tower. The makeup water was a combination of surface and well water, with a recent addition of RO reject water, which now provided approximately 30% of the makeup requirements. The system control limits were set using French Creek software to adjust for variations in makeup chemistry from time to time.

Some process exchangers operated with process inlet temperatures of 305 °F, and cooling water flow rates as low as < 1 foot per second. While this system had a history of corrosion and deposition problems due to flow/ temperature limitations, it operated successfully from turn-around to turn-around, with typical hydroblasting and some retubing and replacement of bundles, due primarily to high heat flux and low velocity issues.

Analyzing the Problem

This system had recently experienced a turnaround, and after startup from the turnaround, it began to experience high mild steel corrosion rates, up to 14 mils per year (mpy), in one portion of the system. An investigation found that a valve had been mistakenly manipulated, resulting in low flow in the portion of the plant where high corrosion rates were being observed. Correction of the flow rate resulted in corrosion rates in that portion of the recirculating loop returning to their normal low level.

Everyone thought the problem was solved.

The water treatment service company soon discovered that the system was still experiencing very high mild steel corrosion rates, approaching 21 mpy, and temperature

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“Correction of the flow rate resulted in corrosion rates in that portion of the recirculating loop returning to their normal low level.” the new RO system. We inquired about the purpose of this chemical and were told that this was a new RO membrane deposit inhibitor feed system.

information indicated a high rate of fouling. Additional testing demonstrated soluble copper levels in the recirculating water as high as 0.7 milligrams per liter (mg/L).

Upon reviewing the control information, the company discovered that a decision had been made prior to the turnaround to discontinue the feed of yellow metal inhibitor. It resumed feeding the azole at a feed rate of 3 mg/L, but the high copper levels and the high mild steel corrosion rates did not return to normal levels. The system then experienced a failure of tubes in a critical exchanger less than a year after the mild steel bundle was replaced.

No one knew the composition of this inhibitor, but a review of the product literature quickly confirmed that the product was a 50% active solution of aminomethylene phosphonate (AMP). I knew from prior patent research on this material that the original patent was owned by the primary manufacturer as a copper sequestrant in bottle-washing operations at glass manufacturing plants.

Investigating Operational Issues

The refinery formed a team of corporate engineering, process engineering, maintenance and operations personnel, water treatment field and headquarters personnel, and two well-known independent consultants to conduct a multi-day, onsite intensive review of all pertinent factors to solve the problem. This group was struck that metallurgical investigations by both the corporate refinery metallurgists and the water treatment supplier metallurgists showed that the failure was caused by very severe pitting combined with deposition of corrosion products.

Pitting rates as high as 140 mpy were projected from the data. A significant amount of the pitting was accompanied by a finding of metallic copper in the pits, in some cases comprising as much as 5% of the deposits. This was occurring despite the verification that the feed of azole was 3 mg/L, based on measurement of the azole in the water. This amount of azole was judged to be sufficient to prevent copper pickup from copper alloys elsewhere in this refinery.

During a lunch break on the third day, the two independent consultants were invited to tour a new steam plant that had been commissioned prior to the turn-around.

While walking the plant, we noticed some chemical drums and a small chemical feed system associated with

Finding the Solution

Further investigation showed that there were no phosphonate tests being performed on the RO reject or on the cooling water. We determined that the amount of this product in the RO reject water would translate into a much higher demand for azole than what was required based on the typical cooling water requirements.

Subsequent phosphonate testing confirmed our suspicions.

The vendor optimized the scale inhibitor feed to the RO inlet, reduced the amount in the RO reject (which reduced the amount in the recirculating cooling water), and adjusted the azole feed to ensure that all of the phosphonate was addressed, and the high corrosion rates returned to normal. The rest of the mild steel bundles were inspected, and the exchangers were hydroblasted to remove the deposits. The system returned to normal.

As luck would have it, I was responsible many years before for introducing a highly successful non-chromate cooling water program incorporating AMP and zinc for another major water treatment supplier. I quickly noticed during field trials that 30-day mild steel coupons in mixed metal systems were coming out of the system with tiny black dots on the otherwise good-looking steel coupons with low mild steel corrosion rates. We quickly remembered the first patents on AMP, and we deduced that the AMP

“We determined that the amount of this product in the RO reject water would translate into a much higher demand for azole than what was required based on the typical cooling water requirements.”

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was causing higher than normal soluble copper in the water, leading to copper plating and incipient pits on the coupons. We confirmed this by testing and added azole to our program whenever it was being used in a mixed metal system, and the copper pick-up dropped back down to the normal 0.05 to 0.1 mg/L background level.

Bob Cunningham is the president of International Water Consultants, Inc. He is a native of Western Pennsylvania and has been working in all fields of water treatment since 1964, when he joined Calgon Corp. after earning a degree in chemistry from the University of Pittsburgh. Mr. Cunningham has worked extensively worldwide with all types of boiler, cooling, and wastewater treatment systems across all of the major industries employing these technologies.

He provides litigation support on a variety of issues, including corrosion, deposition, and microbial damage, as well as the control of waterborne pathogens, such as Legionella. He and his wife, Linda, live in Grass Valley, California. Mr. Cunningham can be contacted at rjc5225@ gmail.com.

Today, when I encounter RO reject being recovered into the cooling water makeup, I check any RO scale inhibitors being used to ensure that if aggressive ingredients are being used, their dosage is optimized and the presence of the ingredient is addressed by the feed of adequate azole.

The moral of the story is that when investigating a problem, make sure that you are casting a wide enough net to include all possible variables.

Capital Eyes continued

CWA hazardous substances and be used to both determine applicability and hazard evaluation. EPA is also considering requiring additional worst-case discharge scenarios based on hazard classification, including the preferred classification system and reasons for its use. In addition, the EPA is considering requiring alternative discharge scenarios. This approach would require facility owners or operators to evaluate additional alternative discharge scenarios to account for more probable discharge scenarios and varying adverse weather conditions that could impact different downstream receptors.

Training Requirements: EPA is proposing additional considerations for employee training given the wide range of CWA hazardous substances covered by this proposed regulation and the potential exposure of employees, volunteer responders, and causal laborers to these substances. EPA is also requiring the facilities to keep logs for five years following training.

Hazard Evaluation. EPA is proposing requirements for developing a hazard evaluation for a worst-case discharge scenario. The intent of this requirement is to ensure that in the event of a worst-case discharge, owners or operators will have pre-identified the areas in which adverse impacts to human health and the environment could occur. The hazard evaluation shall include CWA hazardous substances with a maximum capacity on site that meets or exceeds the threshold quantity, including cautionary response considerations, health hazards, fire and explosion hazards, chemical reactivity, hazard classifications, and physical and chemical properties.

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Drills and Exercises. EPA is proposing requirements to develop a drill and exercise program that is designed to periodically test the ability of response personnel to ensure the safety of the facility and to mitigate or prevent discharges of CWA hazardous substances. A drill and exercise program includes tabletop and field exercises, both announced and unannounced.

This proposed rule can be found in the March 28, 2022, Federal Register.

Janet Kopenhaver is president of Eye on Washington and serves as the AWT Washington representative. She can be reached at (703) 528-6674 or janetk@eyeonwashington. com.

the ANALYST Volume 29 Number 2

Beyond Water

But Is It Appropriate?

Mike Henley, MD Henley & Associates

Appropriate: (adj.) Correct or right for a particular situation or occasion.

—Cambridge Dictionary “Appropriate” is a key concept for success in life because, when paired with moral values, it helps to guide how we live our lives and conduct ourselves in work and social situations. It can lead us to make good decisions and protect against hurtful actions.

For me, the ideas associated with this simple adjective took on a whole new meaning during the final months of my mother’s life. For illustrative purposes, I will briefly pull out some lessons learned when aiding my mom during the last months of 2019. Then we will examine the very real question, “Is this decision appropriate?” in the context of helping a close friend or loved one.

The Phone Call

On August 22, 2019, my wife and I had gone to lunch.

While eating, my cellphone rang. I answered, and it was Courtney, the director of the Clermont Park Day Adult Program, calling to let me know that mom had collapsed during lunch and was on her way to the hospital. After getting the pertinent details, we left quickly and headed over to the hospital to meet her in the emergency room.

We learned that the medical staff was working on a diagnosis, so tests like an ultrasound of her brain were already in the works. After the tests, they determined that she apparently had suffered a severe seizure, which was why the ambulance staff had done an endotracheal intubation to protect against injuries. Next, she was admitted into the intensive care unit until she recovered enough to move into regular hospital room and ultimately, to a rehab facility.

One of our early tasks was to find someone who could help with placing mom in an assisted living home. Kelly, who a friend referred us to, began reaching into her network to look for good matches. In the meantime, at the rehab facility, she was supposed to get help with mobility tasks so she could walk again (with a walker) and be able to transition into assisted living.

We thought the issue of where she would move to was settled in mid-September. Serenity House, which operates a network of group assisted-living homes in Metro Denver, had agreed to take mom into a home that could work with single-assist patients. Unfortunately, the night before the move was to occur, she suffered a fall at the rehab facility, partly due to inattentiveness by the care staff. Suddenly, she became a “two-assist” patient, and the plans with Serenity House fell through. What followed were two more hospitalizations, two more rehab sessions, and gaining a new appreciation for how to answer the question as to whether a particular decision or wish is appropriate, or simply an unrealistic desire.

For the remainder of this article, we will focus on how the concepts behind the simple adjective “appropriate” can help guide decision-making when one is involved with a loved one who needs your help. For the purposes of this discussion, I will draw upon personal experiences with helping my parents and other relatives, as well as the experiences of friends and relatives.

Lessons Learned

At that point, it was obvious that she would not be able to return to live in our home, because now her care needs were beyond what we could easily provide. So, the goal became getting her help to regain strength so that she could move into an assisted living group home.

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It was during this time that I began to learn new concepts about overseeing someone’s care. One of the key ideas was “single assist” and “two assist.” For those who have yet to confront those terms, in the healthcare field, one way a patient is assessed is based on their level of mobility and likelihood of falling. Someone who is considered fully mobile is able to walk and can take the ANALYST Volume 29 Number 2

Beyond Water continued

care of tasks such as bathing or using the toilet without any assistance. A single-assist person is less mobile and will often rely on a cane, walker, or wheelchair for mobility. Many times, the same individual will need help from another person to move around and for tasks like dressing, bathing, toileting, and getting into bed.

A single-assist person can still help the caregiver when being moved. A two-assist person is simply weaker and requires the help of two people for tasks like using the bathroom, bathing, moving around, or getting into bed.

In either case, the goal of the assistance is to keep the patient safe and protect against accidents in the restroom or falling while walking.

was inappropriate for her. Next, we will examine the idea of appropriate versus inappropriate for the following living arrangements: living independently or with family members, assisted living, and long-term care.

I also learned that most assisted living facilities are one assist or less. Sometimes, a facility may have locations with more staff so that they can take on two-assist patients, but often there are waiting lists for admission.

At that point, a nursing home could be the wiser choice.

Is the home safe to live in, and is the loved one physically able to stay in the home? If not, what retrofitting is needed, and can the loved one afford to pay for the changes?

Applied to Real-Life Situations

For the remainder of this article, we will look at different living situations, when it is appropriate for particular choices, and the questions a decision-maker (often a POA) might need to consider with input from other family members as well as the person you are assisting.

Living Situation When we worked with Kelly, she offered one of the most profound statements I’ve heard on this subject: “You want to look for a place to live that not only can provide acceptable care on the ‘good’ days, but also on the ‘bad’ days.”

What does that mean? Essentially, you want a place where your loved one can also receive appropriate care on the days when they might have trouble walking or using the toilet, and a place that has the ability to adapt when one’s health baseline changes. For example, changes in one’s ability to walk to the point of needing a walker, and then needing a wheelchair, etc. The key word is “appropriate.” Appropriate care makes sure you are safe, and it means that the facility has caregivers who are able to provide help for one’s particular baseline.

In the case of my mom, the moment she became a two-assist person, it became obvious that our dream of her living in an assisted living group home situated in a quiet neighborhood was no longer feasible, but it also

Living Independently Let’s face it. As we all face our “golden years,” most wish to continue living in the homes we’ve grown used to and may have lived in for decades. Here are a few questions to consider for whether or not continuing this arrangement is appropriate. Note: In this section, we will use the singular tense, but this can refer to one person or a couple that a care overseer is helping.

Can the loved one still take care of home chores (e.g., cleaning, laundry, cooking, yard work) and shopping?

If not, can help be found for home chores, shopping, and caregiving?

Can the loved one use a medical alert device or do they have the ability to use a cellphone to call for help?

Is there a support network willing to help directly or to find outside aid when needed?

How will the loved one get to medical appointments?

Does the loved one have the financial resources to sustain this living arrangement?

Key question: Do the individual(s) overseeing care think this is a viable and sustainable option, or is it being forced by the loved one?

Comment: Obviously, each situation is different, so it is wrong to make “cookie cutter” decisions based on answers. Still, if it is hard to give a satisfactory answer to nearly all these questions, then this is a red flag and it is likely time to consider another option, or it is time to hire caregivers.

Living With Family Member(s) This approach can be an option for a loved one when 84

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Beyond Water continued

they can no longer live independently. Essentially, it is a form of assisted living, but with family, where the family and outside contracted helpers aid the loved one.

A related approach would be for a family member(s) to move into the friend or loved one’s home. In either case, here are some questions to consider: Do you have space to comfortably house the loved one?

Are any changes needed to accommodate your guest during this time? (e.g., installing grab bars in the bathtub, installing a walk-in shower) Will you ask the loved one to pay rent or otherwise help defer any additional household expenses?

Will outside caregivers be brought in, or will members of the household provide care needed by the loved one?

Key question 1: If the loved one requires assistance, are family members willing and able to help, or would that only be possible with an outside caregiver?

often based around a monthly or weekly schedule.

This care can be based around the resident's previous doctors or through medical practices with which the facility works. In the first case, transportation must be arranged to reach appointments; in the second instance, the doctors and other medical professionals often come to the assisted-living facility. Likewise, arrangements can be made for prescriptions to be filed by a pharmacy the facility works with, so it is not necessary for the care overseer to make special trips to an outside pharmacy.

Exercise, entertainment, and social activities are brought in by outside helpers on a scheduled basis, unless the location is large enough to have an in-house social director.

In the remainder of this section, we will briefly look at two common options found in assisted living homes.

Apartments. These are often located within a care facility that offers everything from independent living apartments or cottages through long-term care. They provide meals and different types of care, such as bathing assistance, help with getting dressed and going to bed, and dispensing medications. There are also regular personal safety checks where a staff member will enter the apartment to ensure the resident is safe and has not fallen. Apartment types can range from anything like a simple studio to having a living room, separate bathroom, and one or two bedrooms. This arrangement provides more privacy and personal space. It works well when the resident is still in better health.

Key question 2: Are the family members agreeable to this change?

Key question 3: Are there any relationship problems that could result in conflicts if the loved one were to stay with this family member?

Moving to Assisted Living Assisted living comes in many forms. It can be a facility that is not tied to any other types of care, or it can be a facility that provides a full spectrum of eldercare, ranging from independent living through nursing home care. There will be a series of questions after the next section, “Moving to Long-Term Care.” These questions relate to evaluating assisted-living and long-term care facilities, and in determining if a particular choice is appropriate.

The downside to this approach is that it does not work well for an elderly person who has become feeble and requires greater assistance. For more than three years, I personally helped my Uncle Ted. His first home under our oversight was an assisted-living apartment of his choosing. However, he was beyond the stage where it was safe for him to live there. I still remember vividly the 5:00 am call when driving my daughter home for summer college break. We were in a hotel in western Oregon, and the caller was from an emergency room at Aurora (Colorado) Medical Center, wanting to speak to me to let me know that Uncle Ted had fallen when using the bathroom that night and had hurt his neck.

Basically, assisted living means a facility where there are caregivers available to cook meals and help as needed with daily life functions, such as getting dressed, toileting, bathing, taking medications, and mobility tasks. These facilities are staffed based on the degree of help needed by the residents. Visits by doctors, nurses, and other medical caregivers is more 85

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As a result of this accident, we soon chose to move him into an assisted-living group home, and it worked well for the final three years of Uncle Ted’s life.

Assisted living group homes. These are individual homes that have been remodeled to serve as assisted living houses for anywhere between four to eight people, depending on the size of the house. Some homes are staffed for up to one-assist care, and others can be staffed for up to two-assist care. The advantage of these homes is that an individual can receive more personalized care than is possible in an institutional assisted living facility. Also, as opposed to an assisted living apartment, the residents are out more in the main living areas of the house, so the caregivers can quickly become aware of a fall or medical emergency. Some of these homes are willing to work with their residents through the last months of their lives, when they might move onto hospice care. In essence, it can be the loved one’s final home, provided the care remains appropriate for their medical needs.

Moving to Long-Term Care Long-term or nursing home care is the next step once it is no longer appropriate from a care perspective to live in one of the three options already discussed. For many, it is considered the least desirable option. We all will remember visits to see friends or relatives in a nursing home, and we remember our various experiences, including the unanswered room call buttons, staff parked in front of computer screens while residents were ignored, and the building odors. Despite these horror stories, there are many well-run care facilities that are clean with attentive staff.

In addition to traditional nursing homes, there are also long-term memory care units for patients with Alzheimer’s or other forms of dementia. These units will have special programs for those patients, and also will have security measures to ensure that patients are kept safe from wandering out of the facility.

Questions to Consider The following are a series of questions to consider when looking at an assisted-living or long-term care facility to determine if it is appropriate. Some of these questions are based on our experience, and others came from medical staff we met in the hospital or the long-term care facility.

What are the ratios of both RNs/CNAs to patients?

What is the average number of years of service for your nursing staff?

Do you have full-time therapists? Do they work weekends?

How do you deal with COVID/the flu/norovirus when patients are sick?

How often is the bedding changed and how frequently are the residents bathed?

Is there a restorative program? How often are the patients seen each week?

What kind of activities does your facility have, and do you encourage patients to participate?

In our case, we learned that for my mom, this was the needed option for the last couple months of her life. Her care needs were now beyond assisted living. Fortunately, we knew of a long-term care facility with a good reputation. Even though they had a waiting list, an opening developed, and she was able to be admitted into the Suites at Clermont Park. The facility had attentive, caring staff and was well maintained. One bonus was that it was associated with the day program mom had attended for about four years, so there were staff who already knew her.

When you enter the facility and walk around, does it pass the smell test?

How quickly does the nursing staff respond to call buttons?

If a patient is no longer able to use the call button, how frequently does the staff pop in to check on the wellbeing of the patient? How often do you make sure the patient has the opportunity to be toileted? Turned in bed?

Does your facility offer memory care?

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In terms of meals, if a patient is unable to feed themselves, will CNAs or nursing staff make sure they have the opportunity to eat? Does your dietary staff take pains to offer variety in meals?

How frequently are care conferences conducted?

What is the name of the physicians group that your doctors are affiliated with?

When the patient has a particular condition, will your medical staff listen to family concerns? Or do they “pull rank” and because they have “MD” or “RN” after their name, insist that it is “their way”? (A key question.)

Closing Thought

When one becomes involved in the situation of an elderly friend or family member, it is important to make choices that are suitable for that person. This can touch many areas. In this article, we have reviewed making decisions that relate to housing arrangements through a series of questions that can be considered when choosing if it is time for the care overseer to take a more active role in decision-making, and then areas that should be considered when making choices about living arrangements.

Disclaimer

For when the time for curative or palliative care is past: Does your facility work with any particular hospice? Is hospice care possible in your facility (through working with a hospice)?

How do you work to ensure a “seamless” transition between long-term care and hospice care?

When there are maintenance issues in the room (e.g., TV), how quickly does your facility’s staff respond?

The content of this article is based on the author’s personal experiences. It is not intended to be professional advice. Readers with questions should seek the advice of licensed legal and medical professionals.

Mike Henley provides consulting services through MD Henley & Associates and serves as technical editor of the Analyst. He formerly was editor of Ultrapure Water Journal for 27 years and has been active in several aspects of water treatment and the associated businesses for more than 30 years. Mr. Henley’s background includes helping with the organization of the technical programs at more than 60 Ultrapure Water conferences, including Water Executive Forums. ©2022, MD Henley & Associates.

Does your facility accept Medicaid?

“Life Beyond Water” is a new column for the Analyst that addresses issues that AWT members face in addition to their important work in the water treatment business. If you have an idea for an article, please feel free to send your suggestion to mdhenleywater@gmail.com. We welcome your input.

What are the visiting hours? If a patient’s condition is more critical, can family members stay overnight?

Are there other areas you might want to tell me about your facility?

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T.U.T.O.R.

Technical Updates, Tips, or Reviews

How to Read an SDS Fred Hopkins, Environmental, Health & Safety Consultant

On March 26, 2012, the Occupational Safety and Health Administration (OSHA) published a final rule that modified the OSHA Hazard Communication (HazCom) standard. This regulation is sometimes called the "Right to Know" standard. HazCom governs how the potential dangers of hazardous chemicals should be communicated to workers.

chose. The number, naming, order, and content of sections varied. Locating a certain category of content might require searching in different parts of different sections in an MSDS. One might encounter two different MSDS for exactly the same material from different sources, and the words describing the hazards could be quite different.

The 2012 HazCom standard adopted the United Nations Globally Harmonized System (GHS) of Classification and Labelling of Chemicals, Revision 3, and made significant changes to how chemical hazards were classified, described on Safety Data Sheets (SDS), and labeled.

This article will not go into detail on OSHA GHS classification of hazards or labeling. The focus will be on understanding and using SDS information.

Since HazCom 2012, SDS are more uniform from company to company. No matter whose SDS you examine ... if you are looking at SDS for the same or very similar materials, you should see identical or nearly identical wording describing the hazards present in the same SDS section. Table A provides a partial copy of the initial portion of Appendix D from the HazCom Standard where OSHA stipulates what line items must be shown in the first three sections of an OSHA GHS SDS.

A few basic HazCom requirements did not change.

Chemical manufacturers and/or suppliers must author SDS for their products, distribute those SDS to users, and label products with corresponding information.

Worker training is also required. Manufacturing company employees and all downstream handlers and users must have ready access to the SDS. However, with the advent of HazCom 2012, many changes did occur. Material Safety Data Sheets (MSDS) became SDS. A 16-section SDS format with prescribed minimum subsections was established. Before, MSDS could be laid out in whatever manner the author might

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If two products from different manufacturers are both corrosive to skin and eyes, both SDS must say, “Danger” and “Causes severe skin burns and eye damage.” (Or there should be two separate statements saying the same thing individually for skin and then eyes.) Those statements will appear in Section 2 of both SDS. A number of other required hazard statements and precautionary statements taken verbatim from Appendix C to the OSHA 2012 HazCom standard will also appear in Section 2.

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Table A: Excerpts from Appendix D to 29 CFR § 1910.1200 (HazCom 2012), Minimum SDS Content for the First Three Sections A safety data sheet (SDS) shall include the information specified in Table D.1 under the section number and heading indicated for sections 1–11 and 16. .... (Some text omitted).

Table D.1. Minimum Information for an SDS Heading

Subheading

1. Identification

(a) Product identifier used on the label; (b) Other means of identification; (c) Recommended use of the chemical and restrictions on use; (d) Name, address, and telephone number of the chemical manufacturer, importer, or other responsible party; (e) Emergency phone number.

2. Hazard(s) identification

(a) Classification of the chemical in accordance with paragraph (d) of § 1910.1200; (Classification criteria are spelled out in Appendices A & B to the HazCom 2012 rule) (b) Signal word, hazard statement(s), symbol(s) and precautionary statement(s) in accordance with paragraph (f) of § 1910.1200. (Hazard symbols may be provided as graphical reproductions in black and white or the name of the symbol (e.g., flame, skull and crossbones); (c) Describe any hazards not otherwise classified (some text omitted)... (d) Where an ingredient with unknown acute toxicity is used in a mixture (some text omitted) a statement that X% of the mixture consists of ingredient(s) of unknown acute toxicity is required.

3. Composition/information on ingredients

Except as provided for in paragraph (i) of § 1910.1200 on trade secrets: For Substances: (a) Chemical name; (b) Common name and synonyms; (c) CAS number and other unique identifiers; (d) Impurities and stabilizing additives, which are themselves classified and contribute to the classification of the substance.

For Mixtures, in addition to the information required for substances: (a) The chemical name and concentration (exact percentage) or concentration ranges of all ingredients (some text omitted) ....

(1) Are present above their cut-off/concentration limits; or (2) Present a health risk below the cut-off/concentration limits. (b) The concentration (exact percentage) shall be specified unless a trade secret claim is made in accordance with paragraph (i) of § 1910.1200, when there is (some text omitted) .... In these cases, concentration ranges may be used.

(Some trade secret text omitted)

Note: Text in italics adds a side note or acknowledges areas where the author deleted sentences from the original Appendix D line items for brevity.

GHS Hazard Communication Elements

Another hazard communication mechanism that was introduced as part of HazCom 2012 is the use of pictograms. Pictograms are graphic representations that identify hazards. The graphic image appears in black on a white background surrounded by a square red border rotated on point to present a diamond shape.

GHS hazard communication includes signal words.

The word “danger” is a signal word on SDS. It indicates a possibility for serious injury or damage to property. Corrosive liquids are an example material where “danger” is used. The word “warning” is the signal word for moderate hazards unlikely to cause permanent injury or damage to property. An example material where “warning” is used would be a liquid that is irritating to skin or eyes. Materials that are not hazardous by OSHA GHS criteria have no signal word.

Figure 1 illustrates some of the pictograms commonly seen on water treatment chemical SDS and labels. In some cases—like the corrosive, oxidizer, flammable liquid, and toxic pictograms—the graphics are identical to graphic images used on (U.S. Department of 89

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Transportation (DOT) labels and placards (but not the same color) for cargo with the corresponding hazards. In other cases, the pictograms are unique to GHS hazard communication. Unlike DOT labels and placards, there is no size stipulation on the pictograms used on SDS or on product labels. Figure 2 illustrates the DOT label and OSHA pictogram graphics for corrosive material side by side. Figure 3 does the same for the oxidizer graphics.

Figure 3: Comparison of DOT and OSHA oxidizer graphics.

DOT Oxidizer Label

Corresponding OSHA Pictogram

Figure 1: SDS pictograms and examples of corresponding hazards.

Corrosive to skin or metal Serious damage to eyes Corrosive to skin or metal Serious damage to eyes Corrosive to skin or metal Serious damage to eyes

Oxidizer

Skin irritant, also used for other moderate hazards unlikely to cause serious harm Skin irritant, also used for

Oxidizer

other moderate hazards unlikely to cause serious Skin irritant, also used for harm other moderate hazards unlikely to cause serious harm

Oxidizer

Carcinogen Serious Health Effects

Toxic

Flammable Liquid

Carcinogen Serious Health Effects

Toxic

Flammable Liquid

Carcinogen Serious Health Effects

Toxic

Flammable Liquid

Hazardous to Aquatic Environment Hazardous to Aquatic Environment

SDS Sections

Figure 2: Comparison ofHazardous DOT and OSHA corrosive to Aquatic Environment graphics.

DOT Corrosive Label

Multiple reasons were given for pictogram use when they were introduced, including overcoming literacy, language, and poor eyesight barriers that sometimes limit hazard communication to some workers. If the worker can’t read or can’t read the language the hazard communication text is in, then no communication is possible. Similarly, if the print is too small or the worker can’t see well enough to read text, even when it is in a reasonable font, the hazard communication is ineffective. On the other hand, one picture is worth a thousand words, and a picture that the worker recognizes can identify a hazard.

As already mentioned, SDS contain 16 sections. These sections are organized into four categories of information that are prioritized to facilitate emergency response and grouped to provide different sets of related information.

The following description details the OSHA GHS layout for sheets that comply with the HazCom 2012 standard.

Corresponding OSHA Pictogram

Sections 1 through 3 contain the information that has the most immediate value following a personal injury exposure, a spill, or some other emergency. That is, what is the material and what do I need to know in an emergency?

Section 1 (identification) lists the product trade name, the intended use, the manufacturer, and an emergency phone number.

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“The word, “danger,” is a signal word on SDS. It indicates a possibility for serious injury or damage to property.”

Table B: Examples of Required GHS Statements for a Corrosive Material UN/International GHS Alphanumeric Designation (not required by U.S. OSHA)

Section 2 (hazards identification) is a summary of the product’s GHS hazard classifications and the most important hazard communication text. It gives the signal word (“danger” if the material may cause permanent or serious injury); lists the required hazard statements; shows the pictogram graphic(s); lists the required precautionary statements, including personal protective equipment and first aid recommendations; and often has additional content of value, possibly including supplemental information or precautions that the manufacturer feels you should be aware of. Where GHS text is provided, OSHA does not require the use of the international GHS system of alphanumeric designations adjacent to all text, but some manufacturers include these corresponding alphanumeric designations, especially for SDS intended for international use. The functional value of such use occurs where the alphanumeric designations can facilitate translations to different languages.

Table B provides examples of a few required GHS statements when a material is classified as corrosive to skin and metal and includes the UN alphanumeric identifiers.

Section 3 (composition/information on ingredients) lists the hazardous chemical ingredients present in the product and gives a percent content or a percent content range. Ranges are used when protection of proprietary knowledge is necessary. Ingredients that make no contribution to the OSHA GHS hazards do not need to be shown. Also, input high or low pH ingredients at formulation are sometimes neutralized during formulation and no longer present in the finished product— and they do not appear in Section 3. In cases where formulation is not a trade secret (e.g., commodity chemicals), ingredient information may be as exact as product specifications allow.

Required Statement

H314 (1)

Causes severe skin burns and eye damage

P308 (2)

If in eyes

P351

Rinse cautiously with water for several minutes. (3)

P338

Remove contact lenses, if present and easy to do.

Continue rinsing.

Notes: (1) The H identifies this statement as a hazard statement.

(2) The P identifies this statement and those that follow as precautionary statements.

(3) Often, one will find a time for rinsing the eyes inserted in this statement or the following statement—15 minutes is common. That is permissible: “... supplementary information on the label is limited to when it provides further detail and does not contradict or cast doubt on the validity of the standardized hazard information.” (29 CFR 1910.1200, Appendix C, C.3.1) Where it says, “on the label,” that implicitly would include use in Section 2 of the SDS, as the listing of required text in Section 2 on the SDS is also the required label text.

Sections 4 through 6 contain information that provides additional guidance on actions that may be undertaken responding to an emergency. For instance, what should I do if a hazardous situation occurs?

Section 4 (first aid measures) expands on the first aid information in Section 2. Text may elaborate on necessary or recommended measures. Likely symptoms following exposure are identified.

Directions are repeated for first aid following exposure by four routes of exposure: eye contact, skin contact, inhalation, and ingestion.

Section 5 (fire-fighting measures) indicates whether or not the material is flammable and provides firefighting measures, including what extinguishing media are recommended and not recommended on and near the product, what off gases are possible under fire conditions, how one might cool containers adjacent to fire, and what personal protective equipment (PPE) firefighters should employ.

Section 6 (accidental release measures) addresses spill response activities. Typical text includes appropriate precautionary statements, PPE recommendations (usually similar or identical to those given in Section

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with metals or exposure to sources of ignition, are listed, as are hazardous decomposition products.

2), suggested emergency procedures, and methods and materials for containment and cleanup.

Sections 7 through 10 tell the reader how to prevent hazardous situations from occurring during storage, handling, and use of the material.

Section 7 (handling and storage) provides precautions for safe handling, including how the material should be stored. If temperature limits exist, they are provided. Incompatible materials are identified so that they can be segregated.

Section 8 (exposure controls/personal protection) lists OSHA permissible exposure limits, American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values, and any other exposure limit used or recommended. If it is advisable to have exhaust ventilation at the point of use to protect workers from inhalation of harmful gases or particulates (local ventilation), that is shown. If not, a common entry is "general exhaust ventilation is adequate," which means that normal HVAC air turnover in typical industrial workplaces is sufficient to maintain acceptable air quality when handling the material. PPE recommendations that mirror or are very similar to those in Sections 2 and 5 are also given.

Section 9 (physical and chemical properties) is a listing of the product's physical properties. Eighteen specific line items are shown in the minimum subheadings prescribed by OSHA in Appendix D to the HazCom rule. Some manufacturers include a few additional supplemental line items. Among the required line items are appearance (physical state, color), odor, pH, boiling point, flash point, and relative density (specific gravity for liquids). Manufacturers are allowed to provide things like pH and relative density (specific gravities of liquids) and a few other line items as ranges or upper bounds or lower bounds (boiling point greater than 212 °F, for example) to protect their proprietary formulas.

Sections 11 through 16 provide a range of additional information that may be of use to the reader. Section 11, toxicological information, is similar to all the previous sections in including line items required by OSHA. The remaining five sections include various EPA (U.S. Environmental Protection Agency), DOT, possibly international, and nongovernmental content that OSHA has no authority over. Consequently, OSHA's HazCom 2012 does not mandate entries in all line items recommended in the HazCom standard. However, many companies include the information to save time on emails and phone calls asking for things like aquatic toxicity data, DOT shipping descriptions, numerical hazard rankings, and other commonly requested product information.

Section 11 (toxicological information) lists possible health effects following exposure to the product or the hazardous ingredients listed in Section 3. Information given in Sections 2 and 4 on likely routes of exposure (inhalation, ingestion, skin and eye contact) is repeated, as are acute symptoms immediately following exposure and the possibility of chronic symptoms developing more slowly. Elaboration is provided if authors feel more detail is warranted. When toxicological data is available on things like acute oral toxicity for laboratory animals (often, rat LD50’s, a statistical average dose required to kill 50% of rats in a test population in milligrams per pound of bodyweight), that quantitative data is given. Similar numerical and/ or qualitative data may appear for dermal toxicity, inhalation toxicity, skin sensitization (allergic response) or inhalation sensitization. Also, if the material or one of the ingredients in the material is listed as a potential causative agent in the development of cancer or some other health effect, that should be acknowledged.

Section 12 (ecological information) provides perspective on the product's hazard to the environment, with special attention to the aquatic environment. If available, aquatic toxicity data is provided. Aquatic toxicities are shown as a given fish species LC50—the statistical concentration of the chemical in water where 50% of the fish in a laboratory study experience fatalities, and/or similar crustacean

Section 10 (stability and reactivity) describes any potential hazards from chemical reactions. If the product is stable under ambient conditions, that is stated. Chemical incompatibilities that may have been indicated earlier in Sections 2 or 7 are repeated with possible elaboration. Conditions to avoid, like contact 92

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individual companies and their SDS authors. Likely components include hazard rankings based on the National Fire Protection Association or the paints and coating industry alternative, the Hazardous Materials Information System; unique state or international compliance content, listings of references used in authoring the SDS, and liability disclaimers.

data, and/or similar algae data. Sometimes, data is given for product ingredients listed in Section 3 when data is not available for an entire formulated mixture. If there is information on the persistence and degradability of hazardous ingredients or bioaccumulative potential (increasing concentration of a contaminant as one moves up a food chain) or mobility in soil, this is where that information is found. If there are any other environmental and/or ecological hazards related to use of the material (e.g., ozone depletion), that may be noted.

Reading an SDS

So, how does one read an SDS? That depends on why a person is reading an SDS.

Section 13 (disposal considerations) addresses waste management, possibly including the disposal of any contaminated packaging. If the material is likely to be classified as an EPA hazardous waste (Resource Conservation and Recovery Act regulated), and if it is designated to be a waste material and not used up in its intended application, that may be acknowledged in this section.

If one is in search of specific items of information, understanding the required GHS SDS layout is helpful.

As described earlier, certain line items and categories of information are located in the same areas on all OSHA GHS SDS. For an emergency phone number, go to Section 1.

Section 14 (transport information) lists applicable DOT classification elements that are needed on labeling and shipping manifests if the material meets DOT hazardous material criteria—UN number, UN proper shipping name, hazard class(es), packing group, and whether or not the material has a reportable quantity (RQ ) or contains a marine pollutant. In rare cases, one may see additional information regarding details for bulk transport safety or bulk transport safety over water, or some other text relevant to international GHS compliance or maritime or air transport safety.

Section 15 (regulatory information) provides a series of line items that summarize potential needs for compliance with regulations. Typically, most of the line items found are related to EPA listings and recordkeeping and communications for things like EPA’s Emergency Planning and Community Right to Know (EPCRA) regulation. Often, there is a line item to note whether or not the product or the product ingredients are listed or not listed on the EPA’s Toxic Substances Control Act list.

If looking for a good description of what the material is and how it may be hazardous, go to Sections 1, 2, and 3. Section 1 will indicate what the intended use of the material is. Section 2 will provide a summary of the hazard communication information in the SDS and what appears on the label. Section 3 will name hazardous ingredients present and provide percent content or a percent content range.

For hazardous components, go straight to Section 3.

For information on cleaning up a spill, go to Section 6.

For exposure limits established by OSHA or ACGIH or some other authority, go to Section 8.

If wondering whether the material is a liquid or a solid, what color it is, pH, specific gravity, whether it is water soluble or a number of other physical properties, then go to Section 9.

For health effects that may result from exposure, go to Section 11.

For aquatic toxicity, go to Section 12.

Section 16, other information, includes the date of preparation or last revision of the SDS. The rest of the Section 16 content is variable and up to the

To determine if submission of EPA/state-managed Tier II’s may be necessary, go to Section 15.

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See Table C for a cross-reference listing of information topics and where those topics are addressed in an OSHA GHS SDS. Table C: Locations for Information on OSHA GHS SDS Information

OSHA GHS SDS Section(s)

Emergency phone

1

Manufacturer/supplier name and address

1

Hazard summary

2

OSHA GHS classification

2

Signal word

2

Hazard statements

2

Pictograms

2

PPE

2, 6, 8

First aid

2,4

Ingredients

3

In case of fire

5

Spill response

6

Handling and storage

7

Exposure limits

8

Appearance and odor

9

pH

9

Specific gravity

9

Flash point*

9

Incompatible materials

10

Toxicology/health effects

11

Environmental impact

12

Waste management

13

DOT shipping description

14

Emergency Planning and Community Rightto-Know Act and similar compliance

15

SDS revision date

16

Summary

SDS contain a wealth of information and play an important role in safety management for those who manufacture, store, sell, ship, handle, or use chemicals.

SDS identify the potential hazards related to a given material and provide strategies for managing those potential problems. When hazards are understood and prudent work practices are followed, incidents and injuries rarely occur. Conversely, when chemicals are handled without paying attention to precautionary language on SDS and labels, the probability of bad things happening increases.

An ounce of prevention has always been, and still is, worth a pound of cure. Anticipate and prevent problems by reviewing SDS and learning everything you can about the materials you work with and sell. Incidents are bad for business.

Fred Hopkins is an environmental, health, and safety (EHS) consultant. During the past 35 years, Mr. Hopkins has worked primarily in the water treatment chemicals industry. He has authored hundreds of water treatment chemical product MSDS and SDS documents. He has also conducted hazard communication training for water treatment chemical manufacturing personnel, salespeople, and customers. As he has worked as a regulatory affairs manager for several water treatment chemical companies, his experience and expertise extends across the broad range of regulatory matters that impact the water treatment industry. Mr. Hopkins is also a long-serving member of AWT’s Legislative/Regulatory Committee and contributor to the AWT Regulatory Overview. He can be reached at fredhopkins74@gmail.com.

*Flash Point: Temperature at which a material will burn if exposed to a source of ignition, typically based on one of several closed cup test procedures.

One more example: You are standing at the edge of a spill.

A forklift driver speared a drum. Workers laid the drum on its side and rolled the puncture above the fluid line.

You are wishing you could read the sideways drum label (maybe mostly on the belly of the drum and drowning in the liquid spill). Please remember, go read the SDS. All of the OSHA GHS HazCom text that is on the label will be in Section 2 of the SDS. Also, the DOT shipping description, if applicable, including the UN number, which is useful when consulting the Emergency Response Guidebook, is provided in Section 14.

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Do you have an idea for a T.U.T.O.R. article? We are interested in topics that touch on different aspects of water treatment and would welcome your input. If you have an article idea, please contact Mike Henley at mdhenleywater@ gmail.com or (303) 324-9507.

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Business Notes

What Skills Do I Need to Become a Great Manager?

Ursula Kralova, Bloomreach

our performance to show the CFO.” How your team members choose to execute that vision is up to them, and allowing them the space to figure out the tactical “how” is important in avoiding micromanagement.

Throughout my career I have managed dozens of people and helped some of them become managers themselves.

I have found, from their experiences and my own, that good management isn’t the result of a one-size-fits-all approach. We each have unique qualities that help us thrive as managers.

Be upfront about what you need and why it matters, check to be certain that those expectations are understood, then trust your team to do the rest.

Despite these differences though, there are a few key traits that all good managers focus on: clarity, trust and openness. As you make your first foray into management, here are some actions you can adopt that will help you work toward these qualities.

Remember That Trust Is Given, Not Earned

Be Detailed About the “What” and “Why” of Your Expectations

Sometimes new managers fail to provide their team members with clear direction because they believe setting expectations around specific goals, deadlines, and measures of success is akin to micromanaging. But, in reality, being upfront and clear about your expectations is the sign of a thoughtful manager who is interested in setting up your team for success.

Many new managers believe trust is earned over time.

They wait for direct reports to prove themselves, using their first weeks or months to see if they can perform at a certain level before bestowing real responsibility upon them. I have always found this to be a mistake, and one that can lead to a really tough relationship. People are hired because they are experts in their field or show potential to do great work. Withholding trust can make them feel that you’re not acknowledging the skills that brought them to the table in the first place, potentially leading to resentment.

I believe that when it comes to a manager and their team, trust should be given, not earned.

When you provide high-level descriptions of what you need from your team members—as opposed to specific details around what you expect them to deliver and when—you may think you’re doing them a favor by keeping your request broad. The result, however, is often that what your team members think you want is not what you actually envision.

Instead, every time you give a team member an assignment, be clear from the beginning about why you’re asking for something to be done and what is expected as an output. For example, if you’re looking for a slide deck highlighting quarterly results for your department so that you can demonstrate a need for a larger budget next year, explain that. Don’t just ask for “a presentation about

This doesn’t mean you hand your team member a laptop on day one and become the absent manager. It means that once you’ve laid out your expectations for a project, you’re not looking over their shoulder to make sure it’s actually getting done. Trust them to do their job, and in doing so you’ll instill confidence and build mutual respect.

Also, remember that this trust extends both ways. As you show your trust in them, it leaves the door open for them to show their trust in you. They will feel comfortable coming to you when things go wrong or they need your help. They will feel safe experimenting, failing, Continued on page 96

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The benefits of contacting Ascent Global Logistics:

Who says logistics has to be complicated? We certainly didn’t. Contact the Ascent team to learn more.

One point of contact to reach thousands of best-inclass carriers.

Ascent Global Logistics 1.800.614.1348 info@ascentgl.com ascentgl.com/awt

Best-of-breed carrier vetting process.

Ascent handles shipment from sourcing to delivery with worry-free tracking visibility.

Dry van, flatbed, and specialized equipment.

Business Notes continued

for you? What do you need from me or the company to get past the roadblocks you’re facing?

and growing from those failures. Trust provides a level of safety that can help people challenge what they think they’re capable of on the road to achieving even more.

Build a Culture of Feedback From the Start

Your team expects feedback from you, but a well-balanced relationship requires that feedback flows both ways. Your direct reports should never feel that your relationship is only about what they can do for you. You’re a team; what you can do for them is just as important.

We often wait for yearly reviews to solicit feedback from our teams, but being a good manager means being open to feedback at all times. Set the tone for open communication early on by scheduling weekly or biweekly one-on-one meetings with each member of your team and frequently asking them to share their thoughts about how you could improve or how you can better work together. Some questions to consider are: Am I clear in the expectations I set? Do I give you enough time to complete your tasks? Does my communication style work 96

In asking these questions frequently and from the start, you’ll show that feedback isn’t just welcomed; it’s expected.

This will make your team feel more comfortable coming to you in the future, whether it’s to offer feedback about you or talk about other challenges they’re facing.

With great management comes great responsibility.

There is a reason for the adage that “people leave managers, not companies.” Being the type of manager whom people actually want to work for is not always easy. It requires a great deal of communication, trust, empathy, and openness—areas that require constant work and reflection.

Above all, it requires a willingness to listen. As I said, there is no one-size-fits-all approach to good management. Take the time to learn what your team needs in order to thrive, then adapt accordingly. ©2022 Harvard Business School Publishing Corp.

the ANALYST Volume 29 Number 2

C A N A D A

2022 Annual Convention & Exposition September 21–24, 2022 | Vancouver Convention Centre

SAVE THE DATE!

Scan the QR-code or go to www.awt.org/annual-convention-2022/traveling-to-canada to learn how to prepare to travel to Canada.

97

the ANALYST Volume 29 Number 2

Advertising Index 29

AMSA, Inc.

21

Metal Samples Company

65

AquaPhoenix Scientific, Inc.

50

Myron L. Company

33

Bio-Source, Inc.

22

Process Engineered Water Equipment

41

Brenntag North America, Inc.

13

Pulsafeeder, Inc.

49

Chem-Met

19

QualiChem, Inc.

23

CHEMetrics, Inc.

7

Quantrol, Inc.

31

EMSL Analytical, Inc.

35

Sanipur US LLC

2

Environmental Safety Technologies, Inc.

100 Special Pathogens Laboratory

98

ICONX Chemicals

74

Uniphos

12

IDEXX

99

Walchem, IWAKI America Inc.

49

International Dioxide

Protecting the WORLD’s Cooling Towers

We are a MANUFACTURER and DISTRIBUTOR Of Specialty Chemicals With outstanding technical & Customer service support

We specialize in the following technologies

What makes ICONX different?

Our People – With over 50-years of application and molecular synthesis experience.

ICONAMINE Low-P White Rust Removal Scale & Corrosion Inhibitors

Our Technology - We have developed special scale & corrosion inhibitor products that effectively treat a systems surface and the system’s water. These products can effectively remove and prevent white rust, are low-P or P-Free, provide surface passivation, and protect all mixed metallurgies including Aluminum, Galvanized, Brass, Copper & Cobalt, Stainless and Mild Steel.

ICONAMINE P-Free Scale & Corrosion Inhibitors ICONAMINE Enhanced Raw Materials ICONX Biocides

ICONX Biodispersants

Our Service & Support –Outstanding customer service and support, with a dedicated team of professionals to help you with everything from order placement, custom lab analysis, to in-field application support.

ICONX Antifoams SAFE ACIDS & CLEANERS Miles Stoffer Miles@ICONXCHEMICALS.COM | 412-719-9900

www.ICONXCHEMICALS.com

98

Laura Sanders Laura@ICONXCHEMICALS.COM | 678-641-6088

the ANALYST Volume 29 Number 2

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