June 2016 - Florida Water Resources Journal

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Michael Delaney Rick Harmon Patrick Delaney Buena Vista Publishing

Published by BUENA VISTA PUBLISHING for Florida Water Resources Journal, Inc. President: Richard Anderson (FSAWWA) Peace River/Manasota Regional Water Supply Authority Vice President: Greg Chomic (FWEA) Heyward Incorporated Treasurer: Rim Bishop (FWPCOA) Seacoast Utility Authority Secretary: Holly Hanson (At Large) ILEX Services Inc., Orlando

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Websites Florida Water Resources Journal: www.fwrj.com FWPCOA: www.fwpcoa.org FSAWWA: www.fsawwa.org FWEA: www.fwea.org and www.fweauc.org Florida Water Resources Conference: www.fwrc.org Throughout this issue trademark names are used. Rather than place a trademark symbol in every occurrence of a trademarked name, we state we are using the names only in an editorial fashion, and to the benefit of the trademark owner, with no intention of infringement of the trademark. None of the material in this publication necessarily reflects the opinions of the sponsoring organizations. All correspondence received is the property of the Florida Water Resources Journal and is subject to editing. Names are withheld in published letters only for extraordinary reasons.

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News and Features 4 Peace River Manasota Regional Water Supply Authority Celebrates Silver Anniversary—Patrick Lehman and Richard Anderson 14 2016-2107 FWEA Board of Directors 15 2016-2017 FWEA Officers, Chairs, and Advisors List 25 FSAWWA Luncheon at ACE16 30 WEF HQ Newsletter—Mónica de Gracia, Randall Marx, and Rafael García 34 Toxicity Smackdown—Joe Squitieri 36 Nutrient Recovery From Municipal Wastewater Treatment Plants: Status and Prospects—Hamidreza Sharifan 40 Florida Section AWWA Delivers—Doug Prentiss Sr. 42 Fighting the Baby Wipes War—Hubert Colas

Technical Articles 6 Cause-and-Effect Study of Biofermentation: A Novel Biosolids Residuals Point Source Reduction Technology—Rob Whiteman and Brad Macek 22 Process Control Strategies for Biological Nutrient Removal in an Oxidation Ditch—Ann Sager, Leslie Knapp, Sarina Ergas, and Gita Iranipour

Education and Training 17 21 27 41 46 47

FSAWWA Fall Conference FWPCOA Region IV Short School FWPCOA Training Calendar TREEO Center Training CEU Challenge ISA Water/Wastewater and Automatic Controls Symposium

Columns 12 C Factor—Scott Anaheim 20 FWRJ Reader Profile—Pam LondonExner

38 FSAWWA Speaking Out—Kim Kunihiro 40 FWEA Focus—Lisa Prieto 45 Certification Boulevard—Roy Pelletier

Departments 39 48 51 54

New Products Service Directories Classifieds Display Advertiser Index

Volume 67

ON THE COVER: Dewatered (cake) biosolids being delivered to a composting facility in central Florida.

This state-of-the-art facility processes 200 wet tons of biosolids daily into high-quality compost that is marketed throughout Florida.

June 2016

Number 6

Florida Water Resources Journal, USPS 069-770, ISSN 0896-1794, is published monthly by Florida Water Resources Journal, Inc., 1402 Emerald Lakes Drive, Clermont, FL 34711, on behalf of the Florida Water & Pollution Control Operator’s Association, Inc.; Florida Section, American Water Works Association; and the Florida Water Environment Association. Members of all three associations receive the publication as a service of their association; $6 of membership dues support the Journal. Subscriptions are otherwise available within the U.S. for $24 per year. Periodicals postage paid at Clermont, FL and additional offices.

POSTMASTER: send address changes to Florida Water Resources Journal, 1402 Emerald Lakes Drive, Clermont, FL 34711

Florida Water Resources Journal • June 2016

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Peace River Facility - 1991

Peace River Facility - 2016

Peace River Manasota Regional Water Supply Authority Celebrates Silver Anniversary

Patrick Lehman and Richard Anderson As we recognize National Drinking Water Week this year, the Peace River Manasota Regional Water Supply Authority celebrated the 25th anniversary of our acquisition of the Peace River Water Treatment Facility.

The Authority, through partnership with the Southwest Florida Water Management District, acquired the Peace River Facility upon the demise of General Development Corporation in 1991. In the past quarter century since the acquisition, the Authority has successfully constructed over $350 million of new infrastructure, increasing treatment capacity and expanding the regional transmission system to create a reliable, safe, and affordable water supply.

The facility, originally

by General Developbuilt 51-mgd Treatment Capacity ment Utilities in 1980, was acquired by the Authority in 1991 with a treatment capacity of 12 mil gal per day (mgd) and has since been expanded to 51 mgd to meet regional demands. Originally serving only a portion of Charlotte County and the City of North Port, the Peace River facility now provides 6-BG Storage Reservoirs

4 June 2016 • Florida Water Resources Journal

over 75 percent of the drinking water supply for Charlotte, DeSoto, and Sarasota Counties, and the City of North Port.

Investments and expansions of the facility over the past 25 years include 39 mgd of treatment capacity, construction of a 6-bil-gal (BG) offstream reservoir, and the largest operating aquifer storage and recovery (ASR) system in the eastern United States, enabling the Authority to be a model for environmentally sustainable and affordable drinking water supply development in Florida.

Florida Rep. Ben Albritton served as the guest speaker at the silver anniversary celebration during the annual Peace River BBQ sponsored by the Friends of Peace Water.

The May 6th event, held under the oak trees at the Peace River facility in DeSoto County, drew a crowd of over 250 guests Rep. Ben Albritton and dignitaries, providing the opportunity to showcase the Authority’s accomplishments and convey the value of water to elected officials and business leaders representing communities in the Authority’s four-county region.

Patrick Lehman is executive director and Richard Anderson is system operations manager at Peace River Manasota Regional Water Supply Authority S in Arcadia.

(Left to right) Authority Executive Director Pat Lehman, Rep. Ben Albritton, and Charlotte County Commissioner and Authority Chair Christopher Constance.

F W R J

Cause-and-Effect Study of Biofermentation: A Novel Biosolids Residuals Point Source Reduction Technology Rob Whiteman and Brad Macek Rob Whiteman, Ph.D., is technical director with ABS Inc. in Fleming Island, and Brad Macek is assistant director with City of Port St. Lucie.

unicipalities and utilities are continuing to face reduced federal subsidies, shrinking budgets, and increasing costs of operations for wastewater treatment plants (WWTPs). Residuals and biosolids handling from the biological wastewater treatment processes are a significant portion of the total

M

Table 1. Disposal, Volume, and Mass Reduction Strategies for Biosolids Processing

Figure 1. Point Source Reduction

Table 2. Pollution Prevention Control Strategies for Residuals and Biosolids Handling

6 June 2016 • Florida Water Resources Journal

cost of operation. The U.S Environmental Protection Agency (EPA) indicates that 40 to 60 percent of the operating costs of a wastewater treatment plant are associated with biosolids handling and disposal. For the past 100 years, the wastewater industry has relied on innovation via new engineering and mechanical process designs to produce less biosolids or to handle residuals more cost-effectively. Purchase of these new designs and equipment has been coupled with the commercial bidding process to maintain competition and suppress costs.

This competition has forced companies to focus on recovery/recycle and reuse under the banner of pollution prevention, leading to numerous technologies for both volume reduction and mass reduction of biosolids prior to various disposal methods, which are presented in Table 1 by function (Whiteman, 2016).

The EPA best management practices prioritize pollution as a hierarchy, starting with point source reduction (PSR), as shown in Figure 1.

As such, point source reduction (PSR) trumps recovery/recycle, which trumps reuse in the prioritization hierarchy. Reduction at the PSR of biological sludge has been left to design fundamentals and the operators to maintain the longest mean cell residence time (MCRT) possible in order to reduce the food-to-microorganism (F/M) ratio, thereby reducing the net yield, and hence, the amount of biosolids produced. Table 2 summarizes the current approaches to pollution prevention for residuals and biosolids handling (Whiteman, 2016).

The premise of activated sludge design has always been based on growing the desired microbes in-situ—in other words, in the biological treatment system. This assumes natural development of the desired bacteria for floc formation to drive good settleability, which is dependent on the MCRT, or the correct bacteria being present in sufficient number to populate the biomass.

Historically, the challenge for designers and operators with extending the MCRT above 20 to 30 days has been the development of excessive amounts of filamentous organisms, which re-

duces biomass settleability and dewaterability, along with fragmentation of the floc, causing poor effluent quality. Typically, WWTPs are therefore operated in the five-to-20-day MCRT range, depending on the design (Eckenfelder, 1998) to meet the National Permit Discharge Elimination System (NPDES), season temperature variations, and comfort level of the operator. The last three decades have seen oxidation ditch designs eliminate primary clarifiers, saving capital costs with resultant higher biological sludge production as primary solids buildup under aeration. This has led to the introduction of various innovative membrane separation designs that have theoretically overcome the dependency on biomass settleability and the need to operate at conservative MCRTs with resultant high energy costs. Many of these membrane systems have to operate at moderate MCRTs to maintain membrane permeability, while the membranes are further negatively impacted by accumulation of fats, oils, and grease (FOG).

Other developments in the last decade have focused on harnessing the biology more effectively for nutrient removal with reduced energy requirements and biosolids production in designs, such as Anammox, by encouraging in-situ growth of the microbes that convert ammonia

Figure 2. Visualization of Viability Versus Mass

to nitrite, then directly to nitrogen gas under anaerobic conditions. The myriad of process designs in the last 100 years of activated sludge have taught designers and operators one thing: There is no one simplistic and elegant solution to wastewater treatment; it is a complex multidisciplinary subject requiring understanding of engineering, operations, and microbiology.

Many utility directors are now asking, “How do we get more out of an existing wastewater facility?” One answer is to develop costeffective PSR technologies to obviate the huge capital and operating costs associated with downstream processing and handling of biosolids residuals.

Continued on page 8

Florida Water Resources Journal • June 2016

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Continued from page 7 Bioaugmentation products have been welldocumented to benefit industrial biological plants (Whiteman 1987, 1989, 1991, 1992, and 1994), but the technology has failed to become broadly validated within the wastewater industry

due to lack of cause-and-effect data. Biofermentation is a biological sidestream reactor process (not product) designed to grow pre-acclimated microbes ex-situ under ideal conditions, thereby minimizing the need for in-situ growth, which is the basis of all current engi-

Figure 3. Impact of Biofermentation on F/V Ratio

Figure 4. Impact of Biofermentation on Secondary Biosolids Production

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neering practices. The primary benefit of a sidestream reactor is better control over the growth of the desired pre-acclimated microbes. A second benefit is the sheer number of microbes that can be added to the system on a daily basis, which is discussed further.

One application of biofermentation is as a PSR technology introduced in 2009 by ABS Inc. The technology was originally developed for the pulp and paper industry to rapidly recover biology of the plant after toxic shocks. Using equipment called biofermentors, the biofermentation process grows bacteria onsite, adjacent to the biological wastewater plant, and injects these cultures on a daily basis. In the municipal sector, demonstrations carried out in 2008 led to an astounding discovery: Biofermentation significantly reduces the mass of secondary biosolids produced per pound (lb) of biochemical oxygen demand (BOD5) removed.

The biofermentation process reduces biosolids production via two main mechanisms: firstly, by increasing the number/viability of specific indigenous BOD5 degraders, thereby reducing the actual amount of food to viable BOD5 degraders; and secondly, by addition of floc formers, which improves biomass settleability, increasing return activated sludge (RAS) concentrations and, in turn, allowing higher mixed liquor suspended solids (MLSS); hence, operation at longer MCRT with lower F/M results in further reduction of biosolids production.

This concept is visualized using the “cupcake” analogy to illustrate the difference between viability and mass. In Figure 2 the cupcake represents the activated sludge floc, which is made up of various constituents, including inorganic and organic matter, the latter of which consists of nonbiological and biological matter. The biological matter consists of bacteria responsible for biodegradation of soluble/insoluble organics as measured by BOD5 removal and those not contributing to BOD5 removal. The specific bacteria that remove BOD5 do so by absorption of organics; by definition, therefore, the BOD5 removal process must take place by specific bacteria on the surface of the floc, which is represented in the left-hand picture by the red sprinkles.

By injection of specific bacteria targeted at BOD5 removal and floc formation, the single-cell bacteria become attached to the surface of the floc and compete for food, as represented in the righthand picture in Figure 2 by the “green sprinkles.”

This increases the viability of the biomass by at least tenfold. This also results in a reduction in the ratio of food/microorganism viability (F/V) of specific BOD degraders, because there are now 10 times more BOD5 -eating bacteria to eat the same amount of food, as shown in Figure 3. Microbial viability was measured with Standard Methods

Agar (SMA) media using standard serial dilution microbiology procedures.

The result of reducing the F/V is to reduce the amount of secondary biosolids produced, irrespective of the actual F/M ratio measured as volatile suspended solids (VSS) and as shown in mathematical modeling work from actual plant data in Figure 4 (actual data shown in Figure 7).

The model predicts that at an F/M ratio of 0.15 lb BOD5/lbMLSS/d a municipal plant without a primary clarifier would produce 0.6 lb of biosolids per lb of BOD5 removed, while with biofermentation, the plant would only produce 0.2lb of biosolids per lb of BOD5 removed, or a PSR of 66 percent with no additional air requirements.

Biofermentation has been proven to reduce secondary biosolids production in many types of wastewater treatment processes. This article focuses on the cause-and-effect work of the Port St. Lucie Glades facility for validating the process for reducing secondary biosolids production, while touching on the potential to increase hydraulic and organic throughput.

Methodology The methodology for the process starts with a laboratory service provided by ABS for the isolation of specific indigenous BOD degraders and floc formers for a particular site. From these cultures ABS creates a unique biomass blueprint of the key indigenous populations to be grown in the biofermentor, or the pre-acclimated microbes. The biofermentation process is operated and supplied

by ABS as a turnkey service on a flat-fee basis. This service includes equipment in the form of a biofermentor to grow the specific indigenous bacteria onsite, along with the necessary materials for growth of the microbes and technical support throughout to demonstrate that the process is achieving the desired performance criteria. There are no capital costs or manpower requirements to the client; only a small operating cost for water and electricity. Batches of microbes are made daily, or on an as-needed basis, by ABS personnel, depending on the specific site in the aeration basin.

Demonstrations are easily executed using trailermounted mobile systems, which are later replaced under long-term contracts with skid-mounted equipment inside a permanent installation.

Table 3. Periods of Data Evaluation (Port St. Lucie Glades Facility)

Table 4. Influent, Effluent, and Design Data (Port St. Lucie Glades Facility)

Table 5. Operational Characteristics (Port St. Lucie Glades Facility)

Port St. Lucie Glades Facility in Florida

25,000 lbsBOD/d or 6255 lbsBOD/basin/d, with hydraulic loads of 3mgd/basin. Historically, the facility had been receiving approximately 12,000 lbsBOD/d, with a flow of 3.7 mgd, and was operating with two aeration basins: 6000lbsBOD/basin/d with flows of 1.85 mgd/basin. Thus, the facility was operating well within design parameters. There were two goals of this study to evaluate the ability of the biofermentation process: 1) To increase throughput and capacity by operating off one train (period 2) 2) As a PSR technology (period 2 and period 3)

Port St Lucie operates a 12-mil-gal-per-day (mgd) facility called the Glades, which was designed as a modified Ludzak-Ettinger-activated sludge plant with no primary clarifiers, four aeration basins, diffused air, anoxic zones, and internal recycle. The plant was designed to handle

The study started in mid-April 2010 and was concluded at the end of October 2010 after seven months. Two mobile-trailer-mounted biofermentation units were used to dose the system with an individualized biomass blueprint of the indigenous microbes. The first six weeks

were taken to stabilize the biofermentation culture and move the inventory to one basin. The periods of data analysis are shown in Table 3, while a summary of the influent, effluent, and design data are provided in Table 4, and operating data in Table 5.

In evaluating the first goal to determine the ability to operate off one train in period 2, the data showed that the hydraulic retention was reduced from 12.99 to 6.65 hours, or almost exactly 50 percent as a result of moving treatment to one aeration basin, while influent BOD5 increased by an additional 2323 lbs BOD5/d, with a total of 14,347 lbs BOD5/day from a base of 12,024 lbs BOD5/d. This represented an increase in organic loading rate of 122 percent above the baseline data. Despite the increase BOD5 load, decrease in hydraulic retention time, and a higher F/M of Continued on page 10 Florida Water Resources Journal • June 2016

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Continued from page 9 0.24, the final effluent BOD5 only rose 34 percent, which is equivalent to the increase in F/M. This resulted in the final effluent BOD5 rising from 47 lbs BOD5/d to 63 lbs BOD5/d, with BOD5 removal efficiencies dropping from 99.59 to 99.53

percent, representing a decrease of 0.06 percent in BOD5 removal at higher F/M. Overall, the demonstration for period 2 represents a hydraulic loading of 133 percent of design, with an organic loading rate of 230 percent of design and only a minute reduction in ef-

Figure 6. Period Versus Biosolids Production (lb Biosolids per lb BOD5 Removed)

ficiency that was caused by the increase in F/M; this increase could have been offset by further adjustment of MLSS to compensate. It is worthy to note that this is consistent with results observed at other facilities.

The second goal was to evaluate the potential of PSR biosolids. After the evaluation of period 2, the plant returned to operation off two basins in period 3 for comparison to the baseline. In order to normalize this data further, analysis was undertaken for periods 1-5 based on lbs biosolids produced per lbs of BOD5 reduced, which is shown in Table 5 and Figure 6 as a mean for the period.

This analysis shows several interesting facts: 1) In period 2, when hydraulic retention time is 50 percent of design, the biofermentation process works to stabilize BOD removal, but becomes less efficient at reducing biosolids production. This may in part be reflective of the increased F/M. 2) In period 3, when hydraulic retention time is within design range, biofermentation reduces secondary biosolids production readily (0.18 lb biosolids/lb BOD5 removed), representing approximately 59 to 53 percent reduction, compared to periods 1 and 4, respectively.

3) In period 4, after the biofermentation process had ceased, the reduction in the biosolids produced continued to a lesser degree (18.9 percent less than period 1) due to the impact of the residual cultures, while in period 5 the plant returned to normal. These results are exactly the same observed in a similar study carried out at the Department of Corrections in Hardee County, Fla. 4) In period 5, after complete washout of the biofermentation bacteria, the process returns to a higher level of biosolids production, with 0.6 lb biosolids/lb BOD5 removed.

The Port St. Lucie Glades facility, while having a very stable flow, was shown to experience large swings in influent BOD load, which caused the F/M to vary enormously. As net biosolids production will vary based on F/M, it was decided to analyze the daily data for period 1 against period 3, as shown in Figures 7. This analysis confirms that during period 3 a significant reduction in biosolids production occurred, which had never previously been observed, and that in fact was irrespective of the F/M ratio.

Consequently, this data have been used to develop equations to model the biofermentation process, as shown in Figure 3. These equations, along with R2 coefficients, are:

Figure 7. F/M Versus Biosolids Production per lb BOD Removed

10 June 2016 • Florida Water Resources Journal

Period 1 – Prior to Biofermentation: y = 0.1096x-0.911 R² = 0.4587

Period 3 – During Biofermentation: y = 0.0347x-0.91 R² = 0.968 The exceptionally high R2 correlation of 0.968 for period 3 shows that biofermentation is a highly predictable, definable process. Subsequent work has used this data for engineering designs using BioWin. Biomass analysis over periods 1-4 showed that the biomass structure became less filamentous and more closed/firm during use of the biofermentaion process. A comparison of periods 1 and 2 are provided in plates 3 and 4. The filamentous scale used is 0-6, where 0 represents no filaments and 6 represents a severely filamentous biomass (Jenkins et al, 1993).

The improvement in floc strutcure during periods 2 and 3 was apparent in other operating data during biofermentation, such as higher return activated sludge concentrations rising from 12-14,000 to 18-22,000 mg/L. In period 3, postbiofermentation filamentous ratings increased, although the deficient photograph, when comparing Plates 5 and 6 with what was recorded on paper during period 4, were filamentous ratings of 3. This data is confirmed by other operational data after ceasing biofermentation in periods 4 and 5. In period 4, wastage rates increased three months in a row despite the F/M remaining the same as period 3 as a result of poorer settleability.

In conclusion, the biofermentation process results at Port St. Lucie showed enormous benefits, both in terms of improving the ability to treat more hydraulically and organically and improving settleability, as well as demonstrating the ability under normal design HRT to reduce biosolids production significantly.

In summary, the biofermentation process has been proven and validated through causeand-effect studies at two treatment facilities as a PSR process for reducing the production of secondary biosolids and associated processing and handling costs without the need for additional aeration. The development of this PSR process has commercially been shown to create a net operational savings to operations without primary clarifiers. The opportunity for facilties with primary clarifiers and anaerobic digestion to benefit from this PSR process is being evaluated further by considering increasing digester capacity to handle higher-value methanogenic fuels, such as FOG. In some cases, this may eliminate the need for construction of another anaerobic digester where plant expansion is occurring, allowing scarce capital resources to be allocated to other projects. For biofermentation, the next logical step is the creation of an adjunct process to create Class A biosolids. This work has started in 2016.

Plate 3, Period 1: Prebiofermentation Filamentous rating 1-2. Open/Closed floc with weak-firm, irregular structure.

Plate 4, Period 2: During Biofermentation Filamentous rating 0-1. Closed floc with firm, irregular structure.

Plate 5, Period 3: Biofermentation Filamentous rating 0-1. Closed floc with firm, irregular structure.

Plate 6, Period 4: Postbiofermentation Filamentous rating 3. Open/closed floc with weak-firm, irregular structure.

Other benefits regarding the ability of the biofermentation process to create additional hydraulic or organc loading capacity deserve further evaluation as an intermediate alternative for maintaining compliance, while design/engineering expansion occurs. Ultimately, the biofermentation process should be considered by environmental engineers as an integral part of the design of future wastewater treatment plants.

• Whiteman, G.R. (1987). The Application of Selected Microorganisms to Aerobic Wastewater Treatment Plants, REGEM, Poster.

• Whiteman, G.R. (1989). The Application of Selected Microorganisms to an Aerobic Wastewater Treatment Plant in the Chemical Industry, Chemical Waste Management, On or Off Site.

• Whiteman, G.R. (1991). The Application of Selected Microbial Formulations in the Pulp and Paper Industry, TAPPI, 1991.

• Whiteman, G.R. (1992). The Application of Selected Microbial Formulations for Enhancing BOD Removal and Residence Time Studies, TAPPI, 1992.

• Whiteman, G.R. (October, 1992). Bioaugmentation Aids Wastewater Systems, Environmental Protection.

• Whiteman, G.R. (March, 1994). Optimizing Biological Processes: A Look Inside the Black Box, Gwinnett Industrial Conference.

• Whiteman, G.R. (April, 2016). Biofermentation: A Novel Process for Reducing Biosolids Production in the Biological Wastewater Treatment Plant, WEF Biosolids Conference, Session 16B, Milwaukee, Wis. S

Acknowledgments The authors would like to acknowledge the demonstrators who operated the biofermentation process, including Roger Slora and Josh Miller.

References • Eckenfelder, W. Wesley (August, 1998). Activated Sludge: Process Design, and Control, 2nd Edition; CRC Press.

• Jenkins, D; Richard, M.G.; Daigger, G.T. (1993). Manual on the Cause and Control of Activated Sludge Foaming, 2nd Edition; Lewis Publishers: Chelsea, Mich.

Florida Water Resources Journal • June 2016

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C FACTOR

Another Year, Another Great Conference, Thanks to Great Volunteers Scott Anaheim President, FWPCOA

he 2016 Florida Water Resource Conference was a great success again this year, and it was in part due to the cooperation of the Florida Water and Pollution Control Operators Association, the Florida Section of the American Water Works Association, and the Florida Water Environment Association.

The conference was held at the Gaylord Palms Resort and Convention Center from April 24 -27 and both the attendance and number of booths sold were up again this year. Holly Hanson did another amazing job and should be commended, along with the others on her staff, for the job they did in making this conference a success. The FWPCOA was well represented again at this conference and I want to thank all the folks that worked at our booth in the exhibit hall: Tim and Terry McVeigh, Al Monteleone, Mike Darrow, and others.

T

Operators Showcase The Operators Showcase that was held on Sunday afternoon and led by our own Tom King was very informative and covered a variety of topics. The two items that stood out the most were a discussion on when we may see a return of computer-based testing (CBT) by the Florida Department of Environmental Protection for water and wastewater licenses and the lead in water crisis in Flint, Mich.

There were so many really good comments on the need for more sites in south Florida for state exams and the possibility of having the exams proctored at health departments until the CBTs are put back in place.

The Flint water crisis discussion brought up some good comments on when operators should speak up when they know something is wrong, and what they should do about it. I believe all of

us will be watching the outcome of this and we’ll all see our local news stations doing stories on how safe our drinking water is, so this will not be going away anytime soon. We as licensed operators have a duty to bring our concerns to the right people and not worry about our job being in jeopardy for coming forward.

This was the second year of the showcase and we plan on doing it again next year, so if you attend the 2017 conference be sure and drop in, have a beer or two, and bring any topic you would like to discuss.

Operators Challenge It was another great year for the Operators Challenge, with teams competing from all over the state. Congratulations to St. Cloud and Gainesville Regional Utilities for sharing first place in this year’s competition. All the teams improved on the times from last year and competition was very competitive this year, so congrats to all the teams that participated.

FWPCOA Reboot, New Website on the Way The FWPCOA is in the process of updating its website, which went live in late April, and Walt Smyser will be giving regional directors and webmasters training at the August board of directors meeting in Ft. Pierce. The new site will provide more access to our training, including registering online, and will support mobile devices. The new site also includes an association management system to provide our members with greater access and functionality to their membership information, which includes, among other things, the ability for them to view and edit their member information in an online database; join and/or renew memberships; and communicate with us by email, social media, telephone, or mail.

One of the other changes is an improved jobs board. This one will require posting of jobs to be done by members. So if your human resources personnel need to post a job, they should sign up for an associate membership

12 June 2016 • Florida Water Resources Journal

($30 a year). There still will be no fee to post jobs.

If you’re a member and we have a valid email address for you, you will get a notification on how to log into the new site when it goes live. However, many members either do not have their email address on file with us, or we are unable to tie your email address to your membership due to name conflicts. Therefore, after the new site is running, if you are a member in good standing and do not receive a notice, please send us an email from the email address you want to tie to your membership, along with your name as it appears in your membership, and your member number, if you have it.

Please note that all nonmembers that have signed up to be on our email list will need to reregister on the new site.

I want to personally thank Walt for all the time and energy that he has exhausted in getting this site up and running, while still maintaining our old site with duct tape and bailing wire until we made the switch. Walt is another example of the people who make this organization so great by volunteering their own time to take on tasks behind the scenes. We often forget that he does have a real job, and so the work he is doing for us is on his own time. I’m sure he has asked himself why he ever agreed to do this, but Walt, we thank you for stepping up.

Online Training The FWPCOA Online Institute presently has 78 active courses and 256 registered students. For the 2017 license renewal cycle, FWPCOA has sold an average of 29 online courses per month, which is greater than the monthly average of 24 courses sold during the 2015 cycle.

Please continue to advise your members of the availability of the Online Institute in your newsletters and at your membership meetings.

We have completed the first 12 months of the 2017 license renewal cycle, so continue to encourage operators to start earning CEUs for the new cycle.

S

Prieto Takes Office as 2016-2017 FWEA President

Lisa Marie Prieto, P.E., BCEE, has begun her term as president of the Florida Water Environment Association (FWEA), following her election at the Association’s annual meeting on April 26.

Lisa holds a bachelor’s degree in engineering from Vanderbilt University. She moved to central Florida shortly after college to work for MPR Engineering on the phase-four expansion of the South Water Reclamation Facility in Orange County. This experience had a profound effect on her and she realized her passion for wastewater and consulting. From there, she spent seven years with CDM Smith, where she was fortunate to work under and learn from some of the best in the business. During that time, she met and married her

2016-2017 BOARD OF DIRECTORS

husband, Ralph Prieto, and had two children, Madelyn and Aiden.

To add variety to her career, she decided to try something new and went to work as a regional sales manager for Carter and VerPlanck. She recently returned to consulting, where she is serving as the office leader and a client service manager for Brown and Caldwell in the Orlando/Maitland office.

Lisa became a member of FWEA shortly after moving to central Florida. She was encouraged by her colleagues at CDM Smith to become active within the industry.

Her mentors instilled in her the value of being part of a professional association. She truly enjoyed the activities and became more and more involved. In 2009 she served as the seminars chair, later became a director-at-large, and then served as vice president in 2014.

She is also a member of FWPCOA and FSAWWA and serves on the Central Florida Engineers Week Committee. Lisa enjoys spending time gardening, cooking, playing tennis and golf, camping, and spending time with her family.

She is a proud resident of Oviedo.S S

Tim Harley President Elect

Kristiana Dragash Vice President

Joseph B. Cheatham Secretary/Treasurer

Raynetta Curry Marshall Past President

Ron Cavalieri WEF Delegate

Paul Pinault, WEF Delegate

George Cassady Director at Large

Gregory Kolb Director at Large

Sondra Lee Director at Large

Suzanne Mechler Director at Large

Michael Sweeney Director at Large

James Wallace Director at Large

Lisa M. Wilson-Davis Utility Council President

Bradley Hayes Operations Council Representative

Kartik Vaith Executive Director of Operations

Karen Wallace Executive Manager

14 June 2016 • Florida Water Resources Journal

2016-2017 Officers, Chairs, and Advisors The following officers, directors, committee chairs, chapter chairs, and student chapter advisors began their terms at the beginning of the FWEA annual meeting in April.

BOARD OF DIRECTORS PRESIDENT Lisa Prieto, P.E., BCEE Brown and Caldwell 407-766-1478 lprieto@brwncald.com PRESIDENT ELECT Tim Harley, P.E. St. Johns County Utility Department 904-209-2626 tharley@sjcfl.us VICE PRESIDENT Kristiana Dragash, P.E. Carollo Engineers Inc. 941-371-9832 kdragash@carollo.com SECRETARY/TREASURER Joseph B. Cheatham City of Tallahassee WRF 850-891-1009 Joe.Cheatham@talgov.com PAST PRESIDENT Raynetta Curry Marshall, P.E. JEA 904-665-7613 marsrc@jea.com WEF DELEGATE Ron Cavalieri, P.E. AECOM Technical Services Inc. 239-278-7996 Ronald.cavalieri@aecom.com WEF DELEGATE Paul Pinault, P.E. CDM Smith 239-938-9600 PinaultP@cdmsmith.com DIRECTOR AT LARGE George Cassady Hillsborough County Public Utilities Dept.

813-272-5977 cassadyg@hillsboroughcounty.org

COMMITTEE CHAIRS

DIRECTOR AT LARGE Gregory Kolb, P.E. CH2M 407-423-0030 gkolb@ch2m.com

AIR QUALITY Darryl Parker Lee County Board of County Commissioners daparker@leegov.com

DIRECTOR AT LARGE Sondra Lee, P.E. City of Tallahassee 850-891-6123 Sondra.Lee@talgov.com

AWARDS Nicole Quinby, P.E. Kimley-Horn 407-409-7005 nicole.quinby@kimley-horn.com

DIRECTOR AT LARGE Suzanne Mechler, P.E. CDM Smith 561-571-3800 mechlerse@cdmsmith.com

BIOSOLIDS Jody Barksdale, P.E., ENV SP Gresham Smith & Partners 813-769-8948 jody_barksdale@gspnet.com

DIRECTOR AT LARGE Michael Sweeney, Ph.D. Toho Water Authority 407-944-5129 msweeney@tohowater.com

COLLECTION SYSTEMS Walt Schwarz CH2M 305-745-3991 Walt.Schwarz@CH2M.com

DIRECTOR AT LARGE James Wallace, P.E. Jacobs Engineering Group 904-636-5432 jamey.wallace@jacobs.com

EXECUTIVE ADVISORY COUNCIL Mike Cliburn 407-513-8242 cliburn1947@gmail.com

UTILITY COUNCIL PRESIDENT Lisa M. Wilson-Davis City of Boca Raton 561-338-7310 lwilsondavis@myboca.us

MEMBERSHIP ACTION TEAM Kristiana Dragash, P.E. Carollo Engineers Inc. 941-371-9832 kdragash@carollo.com

OPERATIONS COUNCIL REPRESENTATIVE Bradley Hayes City of Tavares 325-742-6485 bhayes@tavares.org EXECUTIVE DIRECTOR OF OPERATIONS Kartik Vaith, P.E. The Constantine Group 904-562-2185 kvaith@tcgeng.com EXECUTIVE MANAGER Karen Wallace 407-574-3318 admin@fwea.org

OPERATIONS CHALLENGE Chris Fasnacht City of St. Cloud 407-957-7104 cfasnacht@stcloud.org PUBLIC COMMUNICATIONS AND OUTREACH Phil Kane, Ed.D. Florida Department of Environmental Protection 407-897-4156 pkane12@att.net

Florida Water Resources Journal • June 2016

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MEMBER RELATIONS Lindsay Marten Stantec Lindsay.Marten@stantec.com WATER RESOURCES, REUSE AND RESILIENCY (WR3) Ricky Ly, P.E. Stantec 407-432-9563 rickyly2007@gmail.com Lynn Spivey ARCADIS U.S. Inc. 813-353-5747 Lynn.spivey@arcadis-us.com SAFETY AND SECURITY Judd Mooso Destin Water Users Inc. 850-337-3915 jmooso@dwuinc.com W. Scott Holowasko Gainesville Regional Utilities 352-335-7359 holowaskows@gru.com STRATEGIC PLANNING COMMITTEE (to be determined) STUDENTS AND YOUNG PROFESSIONALS Tyler Smith Carollo Engineers Inc. 813-888-9572 tsmith@carollo.com TRAINING AND CONTINUING EDUCATION Kenneth Blanton, P.E. Black & Veatch 407-419-3570 BlantonKM@bv.com UTILITIES MANAGEMENT Rick Nipper Toho Water Authority 407-944-5071 rnipper@tohowater.com WASTEWATER PROCESS Laurel Rowse AECOM 813-471-7353 laurel.rowse@gmail.com

CHAPTER CHAIRS

STUDENT CHAPTER ADVISORS

BIG BEND Shanin Speas-Frost, P.E. Florida Department of Environmental Protection 850-245-2991 shanin.speasfrost@dep.state.fl.us

FLORIDA ATLANTIC UNIVERSITY Dr. Daniel Meeroff 561-297-3099 dmeeroff@fau.edu

CENTRAL FLORIDA Damaris Noriega Reiss Engineering (407) 679-5358 dnnoriega@reisseng.com FIRST COAST Teri Shoemaker, P.E. St. Johns County Utility Dept.

904-209-2652 tshoemaker@sjcfl.us MANASOTA Mike Knowles, P.E. Greeley and Hansen 941-378-3579 mknowles@greeley-hansen.com SOUTHEAST Amy Hightower CDM Smith 561-571-3800 hightoweram@cdmsmith.com SOUTHWEST Dustin Chisum AECOM 239-278-7996 dustin.chisum@aecom.com TREASURE COAST Christine Miranda, P.E. Holtz Consulting Engineers Inc. 561-575-2009 Christine.Miranda@holtzconsulting.com WEST COAST Alice Varkey, PEng GHD 813-971-3882 Alice.Varkey@ghd.com

Tim Ware, P.E. ARCADIS 813-787-8466 timothy.warepe@gmail.com

16 June 2016 • Florida Water Resources Journal

Dr. Fred Bloetscher 239-250-2423 fbloetsc@fau.edu FLORIDA INTERNATIONAL UNIVERSITY Dr. Berrin Tansel 305-348-2928 tanselb@fiu.edu UNIVERSITY OF CENTRAL FLORIDA Dr. Steven Duranceau, P.E. 407-823-1440 steven.duranceau@ucf.edu UNIVERSITY OF FLORIDA Dr. John Sansalone 352-281-5806 jsansal@ufl.edu UNIVERSITY OF MIAMI Dr. James Englehardt 305-284-5557 jenglehardt@umiami.edu UNIVERSITY OF NORTH FLORIDA Dr. Chris Brown, P.E. 904-620-2811 Christopher.j.brown@unf.edu UNIVERSITY OF SOUTH FLORIDA Dr. Sarina Ergas 813-974-1119 sergas@usf.edu Dr. James Mihelcic 813-974-9896 jm41@usf.edu FAMU/FLORIDA STATE UNIVERSITY Dr. Youneng Tang 850-410-6119 ytang2@eng.fsu.edu FLORIDA GULF COAST UNIVERSITY Dr. Simeon Komisar 239-590-1315 skomisar@fgcu.edu

FWRJ READER PROFILE What organizations do you belong to?

AWWA, FSAWWA, and its Region IV.

Pam London-Exner Veolia North America, Tampa Work title and years of service.

I have been laboratory manager at the Tampa Bay Regional Surface Water Treatment Plant for 14 years in July.

How have the organizations helped your career?

I became a member of FSAWWA a couple of years after I started working in drinking water. While working for Veolia I started becoming a more active member by being involved with the Biological Contaminants Committee, and I now serve as the chair for the Technical and Education Council. The AWWA/FSAWWA has provided continuing education and an extensive network of colleagues that I can contact if I have a technical question. I know I can find an answer to any question I have that involves drinking water and drinking water treatment because of FSAWWA.

What does your job entail?

I am responsible for making sure the quality assurance and quality control for the drinking water produced at the plant meets and/or exceeds the contractual, state, and federal guidelines. This includes the sample collection planning, in-house laboratory sample analysis, and data evaluation of the contract lab sample analysis 365 days a year. I also work on research projects involving the fullscale and pilot plant. On some days I act as a tour guide for visiting groups, and on others, I may do outreach for school groups and give talks at the schools in the area. In addition, I help other Veolia sites with laboratory audits or consulting on how their labs best meet the company and regulatory requirements.

Education and training you’ve taken.

I have a bachelor of science degree in geology from Western Carolina University and a master’s degree in public health from the University of South Florida, specializing in environmental health.

What do you like best about your job?

Safe drinking water is one of the most essential needs of life. Doing the lab work to ensure that the drinking water is safe is probably what I like best, but educating others about drinking water treatment is a lot of fun, too. I am a total lab geek and I know I can’t fix the world, but I know I can help provide safe drinking water, and I enjoy that the most.

20 June 2016 • Florida Water Resources Journal

What do you like best about the industry?

I really like the constant ongoing research that goes on in our industry. It never stops, and best of all, everyone wants to share what they learn. It doesn’t seem to matter if it’s someone with a formal education or just someone who has learned everything on the job. We have a very active community in the water treatment industry and everyone is always trying to learn more.

What do you do when you’re not working?

This year I was the chair for the FSAWWA Region IV Best Tasting Drinking Water Contest, and I am the current chair for the FSAWWA Technical and Education Council. When I get time I try to play in my craft room, making cards or trying to quilt. Most of all I enjoy getting away with my husband, Tom, to cruise or spend time at our cabin in North Carolina. S

2016 FSAWWA Region IV Best Tasting Drinking Water Contest at Homosassa Springs State Park.

F W R J

Process Control Strategies for Biological Nutrient Removal in an Oxidation Ditch Ann Sager, Leslie Knapp, Sarina Ergas, and Gita Iranipour he occurrence of same-time nitrification and denitrification, within a single reactor and without distinct aerated and nonaerated zones, is commonly referred to as simultaneous nitrification/denitrification (SND). Wastewater treatment systems exhibiting SND typically have relatively long mean cell residence times (MCRT); aeration equipment that creates nonuniform flows, such as mechanical aerators; and an operating procedure to limit oxygen input (Daigger, 2014). Three mechanisms have been proposed for SND, including the existence of: 1) aerobic and anoxic zones within the reactor, 2) aerobic and anoxic zones within floc particles, and 3) novel microorganisms with alternative biochemical pathways. The SND processes can be difficult to control because they depend largely on the bioreactor configuration, bulk dissolved oxygen (DO) concentration, and floc size (Jimenez, 2014); however, significant advantages of SND over conventional biological nitrogen removal (BNR) include: 1) reduced tank requirements and 2) reduced consumption of carbon, oxygen, and alkalinity.

Activated sludge models (ASMs) are used in the design, upgrade, and optimization of wastewater treatment plants. Modeling can be a powerful tool for troubleshooting and increasing understanding of plant operations; however, there have been few published modeling studies of SND systems. The overall goal of this study was to develop, calibrate, and verify a SND process model of the Falkenburg Advanced

T

Wastewater Treatment Plant (AWWTP) in Hillsborough County in Tampa; a preliminary assessment of enhanced biological phosphorous removal (EBPR) was also performed. The AWWTP uses a Carrousel® oxidation ditch system to achieve SND. BioWin model calibration was performed using whole-plant influent, effluent, and operational data. The calibrated model was used to assess the facility’s operations and recommend improvements in process control strategies. Although the plant continually meets and exceeds its permit requirements, improvements in process control strategies have the potential to improve energy efficiency and decrease chemical use, sludge production, greenhouse gas emissions, and costs.

Materials and Methods Site Description and Model Setup The AWWTP is a BNR facility, with an annual average influent flow rate of 9.27 mil gal per day (mgd) and a permitted annual average flow rate of 12 mgd. The plant has permit limits for biological oxygen demand (BOD5), total suspended solids (TSS), total nitrogen (TN), and total phosphorus (TP) of 5, 5, 3, and 1 mg/L, respectively. Oxidation ditches are used to achieve SND and phosphorus uptake. The oxidation ditches are preceded by anaerobic selectors, which improve sludge settleability and initiate EBPR. Aluminum sulfate (alum) addition is used for additional phosphorous removal. The oxidation ditches at the AWWTP

Figure 1. Falkenburg AWWTP Layout in BioWin

22 June 2016 • Florida Water Resources Journal

Ann Sager is a graduate student in the department of civil and environmental engineering, and Sarina Ergas, Ph.D., is a professor is a professor of civil and environmental engineering at the University of South Florida in Tampa. Leslie Knapp is operations and maintenance engineer with Brown and Caldwell in Rancho Cordova, Calif.

Gita Iranipour, Ph.D., is senior engineering specialist in technical services at Hillsborough County Public Utilities Department in Tampa.

were modeled as a loop of 10 unaerated, completely stirred tank reactors (Abusam, 2001) and two mechanically aerated reactors, equally dividing the volume of all four trains (Figure 1).

Model Calibration and Verification Variables chosen for model calibration and verification were mixed liquor suspended and volatile suspended solids (MLSS, MLVSS), and effluent nitrogen species (Total Kjeldahl Nitrogen [TKN], NH4+, NO3-, NO2-). Historical data from a three-year period (Sept. 1, 2010 to Aug. 31, 2013) were exported from the AWWTP Hach WIMSTM system and used for calibration (Sept. 1, 2010 to Aug. 31, 2011) and verification (Sept. 1, 2011 to Aug. 31, 2012). Since only average daily flows were available from historical data, a rough estimate of diurnal influent flow patterns was obtained by viewing supervisory control and data acquisition (SCADA) trends over a 24-hour period. The typical diurnal flow pattern was applied to all average daily flows to create hourly influent data sets.

Analytical Methods Measurements of TSS and volatile suspended solids (VSS) and total and filtered chemical oxygen demand (COD) were performed on composite influent and effluent samples using Standard Methods for the Examination of Water and Wastewater (APHA et al, 2012).

Readily biodegradable COD (rbCOD, flocculated-filtered COD) was measured using the method of Mamais et al (1993). Grab samples were also collected to investigate biological phosphorous removal from four sample points

along the treatment train: 1) influent, 2) anaerobic selector, 3) oxidation ditch, and 4) secondary clarifier. A portion of samples 2, 3, and 4 were allowed to settle for several minutes to obtain supernatant samples, which were immediately filtered with 0.45µm syringe filters.

Samples were placed on ice and analyzed within eight hours of collection for total and reactive phosphorus using Hach (Loveland, Colo.) TNT 843 and 845 kits (Standard Methods 4500E).

Table 1. Combination of Kinetic Parameters Tested During Model Calibration

Model Goodness of Fit and Sensitivity The average sum of absolute residuals (SAR) in Equation 1 was calculated to determine goodness of fit of modeled to observed concentrations of effluent ammonia, nitrate, and nitrite.

Average SAR = ∑n(i=1) |ym.i-yo,i |

[1]

n Where ym is the modeled output, yo is the observed output and n is the number of SARs that were calculated for each simulation.

These values were compared for several simulations with different arrangements of four kinetic parameters (Table 1). The adjusted parameters were “heterotrophic DO half sat.”, “aerobic denit. DO half sat.”, “ammonia oxidizer DO half sat.”, and “anoxic nitrite half sat.” switching functions. The heterotrophic and aerobic denit. DO half-saturation constants were combined into one parameter in the latest BioWin edition; an older edition of BioWin was used in this study, and the two parameters were kept equal for compatibility with newer versions. The number of simulations and combination of parameters were limited due to time constraints. The heterotrophic and aerobic denit. DO half-saturation constants were adjusted based on suggestions in the literature (Envirosim, n.d.) and previously published SND modeling work (Jimenez, 2010).

Other model parameters may achieve a better fit to observed data; however, parameter adjustment should be done with care to avoid unrealistic values. Note that the yearlong simulation period resulted in a relatively long simulation time of approximately four to five hours.

Sensitivity analysis of the BioWin model was performed to determine which parameters were the most influential to the outputs of the model. Five parameters were chosen for the sensitivity analysis based on previous modeling by Jimenez et al (2010). A normalized sensitivity coefficient method (Eqation 2; LiwarskaBizukojc et al, 2010) was used to compare the percent change in output value to a 10 percent change in input values (note that some rounding off was required).

Continued on page 24

Figure 2. COD Results From Wastewater Characterization for Influent n=5 and Effluent n=2

Table 2.

Influent TSS and VSS in Composite and Grab Samples

Figure 3. Total and Filtered Influent COD Florida Water Resources Journal • June 2016

23

Continued from page 23 S = (Δy/y)

[2]

(Δx/x)

Where S is the sensitivity coefficient, y is the output value (e.g., nitrate) and x is the input value (e.g., half-saturation coefficients).

The half-saturation coefficients are located under a heading entitled “switches” in the BioWin simulator. These parameters act as on/off switches by either turning on or off activity of groups of bacteria under certain environmental conditions. For example, the heterotrophic DO half-saturation coefficient turns off the activity of ordinary heterotrophic

Figure 4. Total and Volatile Influent Suspended Solids

Figure 5. Total and Reactive Influent Phosphorus Table 3. BioWin Wastewater Fractions

24 June 2016 • Florida Water Resources Journal

organisms under low DO conditions. Similarly, the anoxic nitrate half-saturation coefficient turns off anoxic growth that uses nitrate under low nitrate conditions.

Results and Discussion The results of the COD analyses on influent and effluent samples are shown in Figure 2.

All influent samples were 24-hour composites and secondary effluent samples were grab samples. Note that the effluent grab sample was collected from the secondary clarifier effluent prior to the media filters. The TSS and VSS values for composite and grab samples are shown in Table 2. BioWin requires volatile or inert suspended solids concentrations to be input into the model. As only historical TSS data were available, VSS concentrations were estimated using the average VSS/TSS ratio determined during supplemental sampling.

Total and filtered COD, TSS, VSS, and total and reactive phosphorus concentrations were measured over a 24-hour period, and the results are shown in Figures 3, 4, and 5. The hourly influent flow was also recorded and used to calculate the mass load per day of each constituent (not shown). Noticeable peaks for both phosphorus and TSS were observed at 10 p.m. The color of the sample at that time was uncharacteristically black, and the results from this sample were not used for estimation of influent characteristics. Average values obtained from historical data or during supplemental sampling were compared with typical values from wastewater facilities in the United States. The historical and measured values mainly fell within the medium to medium-high range.

A commonly encountered issue with activated sludge modeling is the lack of needed input data. For this study, some wastewater fraction values were calculated using the results from the COD analyses, while others, such as the unbiodegradable particulate fraction, were estimated using the BioWin Influent Specifier Excel worksheet. The wastewater fractions that were input into BioWin are shown in Table 3.

Kinetic parameters that were used to model nitrification and denitrification within the oxidation ditch are shown in Table 4. Tables 3 and 4 also show comparisons between the calculated and calibrated values and the BioWin default parameters.

Modeled and observed MLSS values are shown in Figure 6. A better fit might be possible if the wasting rate were adjusted to more accurately reflect dynamic plant wasting activated sludge (WAS) wasting rather than using a constant average value (0.234 mgd). A poor fit was observed between modeled and observed

MLVSS (data not shown), most likely due to alum addition for phosphorous removal, which was not incorporated into the model. Metal hydroxides, such as those formed during alum addition, are oxidized during VSS analysis in the muffle furnace, which will result in a falsely high MLVSS concentration (Jeyanayagam and Husband, 2009).

Modeled and observed TKN results are shown in Figure 7. The observed data were consistently below the model output, most likely due to additional nitrification in the filters, which was not accounted for in the model.

Modeled spikes in effluent TKN concentrations corresponded with high influent TKN loads experienced at the facility. At the Falkenburg facility, operators adjust mechanical aerator speeds based on influent ammonia loads; however, the model maintained a constant DO set point.

Fine-tuning model aeration settings to better reflect practices at the facility could improve the model goodness-of-fit.

The results of sensitivity analysis (Table 5) show that ammonia oxidizing bacteria (AOB) maximum specific growth rate has the greatest influence on effluent ammonia concentrations.

The maximum specific growth rate for nitrite oxidizing bacteria (NOB) does not influence ef-

fluent ammonia, but influences effluent nitrite and nitrate. The combined heterotrophic/aerobic denitrification DO half-saturation constant influences effluent nitrate, as this constant switches on the activity of anoxic heterotrophs at low DO. The AOB DO half-saturation constant was only slightly influential on effluent ammonia, while the anoxic nitrite half-saturation constant mainly influenced effluent nitrate.

The anoxic nitrite half-saturation constant switches off anoxic growth process at low nitrate concentrations. Additional bench-scale tests are currently being conducted to understand the

fate of nitrogen in the system under varying operating conditions. These studies will also allow a comparison of kinetic parameters for SND models obtained using both model calibration, with whole plant data and experimental studies.

The results of the analysis of total and reactive phosphorus at various points in the treatment train are shown in Figure 8. Although the samples size (n=2) is low, the results indicate that EBPR is taking place at the facility. A characteristic release of phosphorus is observed in Continued on page 26

Table 4. Biowin Kinetic Parameters

Florida Water Resources Journal • June 2016

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Figure 6. Observed (green squares) and Modeled (pink line) MLSS Concentration

Continued from page 25 the unaerated selector, followed by very low phosphorus in the effluent of the aerated reactor. The average release of phosphate in the selector was 32 mg/L, and the total amount of phosphate removed was 45 mg/L. Similar phosphate release and uptake were reported by Henze (2008), with a phosphate release of 45 mg/L, uptake of 57 mg/L, and total removal of 12 mg/L. It is not possible to assume the removal of phosphorous in the ditch is fully attributed to EBPR since alum is also added for chemical phosphorus removal. Alum is dosed at a constant rate of ~260 gal per day (gpd) into a splitter box after the oxidation ditches and before the secondary clarifiers. Flow-pacing of alum was recommended to reduce chemical costs, sludge production, and possible impacts of alum on the biological process.

Conclusions

Figure 7. Observed (red squares) and Modeled (blue line) Effluent TKN Concentration

Table 5. Sensitivity Analysis for Kinetic Parameters

Operations staff at the AWWTP consistently meet and exceed National Pollutant Discharge Elimination System (NPDES) permit limits; however, improvements in operations have the potential to reduce sludge production and energy and chemical use. These savings will reduce emissions of greenhouse gases and costs to the county ratepayers.

A BioWin model was created for the AWWTP. Data compilation and reconciliation conducted during this study highlighted many good practices in plant operation and monitoring. Three areas where improvements could be made to advance efficiency of operation were identified during this study: 1) flow-pacing alum addition for phosphorus removal, 2) adjusting WAS wasting based on MCRT, and 3) implementation of online aeration control based on ammonia concentration. This project also provides an example of the use of BioWin to model SND processes. Additional bench-scale experiments are currently being conducted to understand SND kinetics under varying temperature and DO concentration conditions.

Acknowledgments

Figure 8. Reactive Phosphorus Profile From Grab Samples Taken Throughout the Treatment Process

26 June 2016 • Florida Water Resources Journal

This work was possible with the help of the Hillsborough County Public Utilities Department and the operations staff at the Falkenburg Advanced Wastewater Treatment Plant. We greatly appreciate the cooperation of Dan Orlosky, plant manager; Marcus Moore, plant supervisor; and the plant operators and their help in collecting samples and data.

This material is based upon work supported by the National Science Foundation Continued on page 28

FWPCOA TRAINING CALENDAR SCHEDULE YOUR CLASS TODAY! June 6-10..........Wastewater Collection C, B ......................Osteen ................$225/255 13-27..........Stormwater C, B** ......................................Pembroke Pines ..$260/290 13-27..........Stormwater A**..........................................Pembroke Pines ..$225/255 13-27..........Wastewater Collection C, B, A** ..............Pembroke Pines ..$225/255 13-27..........Water Distribution Level 3, 2, 1** ............Pembroke Pines ..$225/255 20-22..........Backflow Repair..........................................Osteen ................$275/305 27-30..........Backflow Tester*..........................................St. Petersburg ......$375/405 24..........Backflow Tester recert*** ..........................Osteen ..............$85/115 27- July 1 ......Water Distribution Level 1 ........................Osteen ................$225/255 27- July 1 ......Wastewater Collection A ..........................Osteen ................$225/255 27- July 1 ......Stormwater A ..............................................Osteen ................$225/255

July 11-15..........Reclaimed Water Field Site Inspector ......Deltona ..............$350/380 18-20..........Backflow Repair* ........................................St. Petersburg ......$275/305 25-28..........Backflow Tester ..........................................Osteen ................$375/405 29..........Backflow Tester recert*** ..........................Osteen ................$85/115

August 8-12..........Fall State Short School ..............................Ft. Pierce

September 5-7..........Backflow Repair..........................................Osteen ................$275/305 14-17..........Backflow Tester*..........................................St. Petersburg ......$375/405 19-23..........Utility Maintenance II ................................Osteen ................$235/255 30..........Backflow Tester recert*** ..........................Osteen ................$85/115 Course registration forms are available at http://www.fwpcoa.org/forms.asp. For additional information on these courses or other training programs offered by the FWPCOA, please contact the FW&PCOA Training Office at (321) 383-9690 or training@fwpcoa.org.

* Backflow recertification is also available the last day of Backflow Tester or Backflow Repair Classes with the exception of Deltona ** Evening classes *** any retest given also

You are required to have your own calculator at state short schools and most other courses.

Florida Water Resources Journal • June 2016

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Continued from page 26 (NSF) under Grant No. DUE 0965743. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the NSF.

References • Abusam, A. (2001). “Development of a Benchmarking Methodology for Evaluating Oxidation • Ditch Control Strategies.” Ph.D. thesis, Wageningen University, the Netherlands.

• APHA, AWWA, WEF (2012). “Standard Methods for the Examination of Water and Wastewater,” 23rd edition, American Public Health Association, Washington D.C. • Daigger, G., Littleton, H. (2014). “Simultaneous Biological Nutrient Removal: A State-ofthe-Art Review.” Wat. Environ. Res. 86(3)245-257.

• Envirosim (n.d.). “Changes To Three Default Kinetic Parameters in BioWin 3.0.1” Online: http://www.envirosim.com/downloads/BW30 1SND.pdf.

• Henze, M., van Loosdrecht, M. C. M., Ekama, G. A., and Brdjanovic, P. (2008). “Biological Wastewater Treatment: Principles, Modelling, and Design.” IWA Publishing.

• Hulsbeek, J., Roeleveld, P., and van Loosdrecht, M. (2002.) “A Practical Protocol for Dynamic Modelling of Activated Sludge Systems.” Wat. Sci. and Tech. 45(6) 127-136.

• Jimenez, J., Dursun, D., Dold, P., Bratby, J., Keller, J., Parker, D. (2010). “Simultaneous Nitrification-Denitrification to Meet Low Effluent Nitrogen Limits: Modeling, Performance, and Reliability.” Proc. WEFTEC2010, New Orleans, La., Oct 2-6, 2010, 2404-2421.

• Jeyanayagam, S and Husband, J. (2009).

“Chain Reaction: How Chemical Phosphorus Removal Really Works.” Water Environ. and Tech. 21 (4).

• Jimenez, J., Wise, G., Burger, G., Du, W., Dold, P. (2014). “Mainstream Nitrite-Shunt with Biological Phosphorus Removal at the City of St. Petersburg Southwest WRF.” Proc.

WEFTEC2014, New Orleans, La., Sept 27- Oct 1, 2014, 696-711.

• Liwarska-Bizukojc, E., and Biernacki, R. (2010). “Identification of the Most Sensitive Parameters in the Activated Sludge Model Implemented in BioWin Software.” Bioresource Technology. 101, 7278-7285.

• Mamais, D., Jenkins, D., and Pitt, P. (1993). “A Rapid Physical-Chemical Method for the Determination of Readily Biodegradable Soluble COD in Municipal Wastewater.” Water Research 27(1) 195-197.

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On and Off

The alternate cycling process can be a cost-effective way to reach nutrient removal goals

Mónica de Gracia, Randall Marx, and Rafael García

ne of the current concerns in the field of wastewater treatment is how to meet new effluent nitrogen limits in a cost-effective manner. The application of oxic and anoxic cycles in a wastewater treatment bioreactor is one effective way.

An on/off strategy applied to aeration makes it possible to maintain nitrification and denitrification in a single aeration reactor. Reducing the time of oxygenation to include anoxic periods, and the possible need to increase solids to provide a longer retention time

O

for autotrophic bacteria, lead to high oxygen transfer rates in the reactor.

Using high-purity oxygen (HPO) enables an oxygen transfer rate increase of up to five times greater than the air-based system's maximum. And using mechanical oxygen injection avoids the reduction of the alpha factor when higher solids concentrations must be maintained in the process, thus maintaining the highest efficiency. With HPO, the biological process becomes a compact and powerful solution for high-strength industrial wastewater treatment.

This strategy of operating with alternating cycles (AC) was tested at a full-scale industrial facility. The AC process has been optimized to obtain the required effluent limits at minimal operation costs. An online sensor for NH4-N and NO3-N has been installed at the full-scale facility to monitor performance. Model-based simulation tools were used to design the required cyclic pattern and eval-

uate an automatic control loop that has also been applied in the real facility and successfully validated.

Truck-Cleaning Facility Description The full-scale water resource recovery facility (WRRF), which treats wastewater resulting from truck cleaning, consists of a membrane bioreactor (MBR) aerated with HPO. Oxygenation is carried out using a mechanically agitated contacting system called the in-situ oxygenation (I-SO™ aerator), developed by Praxair Inc. (Danbury, Conn.). The plant treats 50 to 100 m3/d of flow intermittently in a 500-m3 volume reactor. Tubular ceramic membranes with 300 kD of membrane pore size are used for solids separation (see Figure 1). An equalization tank stores the effluent and feeds the MBR for about 10 hours on working days. Considering both the het-

Figure 1. The biological reactor with the mechanical high-purity oxygen injection aeration tank (left), equalization tank (center), and the membrane system (right).

30 June 2016 • Florida Water Resources Journal

erogeneous origins of the wastewater and the discontinuous feeding pattern, the biological model has a highly variable inflow.

The wastewater characteristics depend on the number of trucks to be cleaned and the goods they transport. The facility will use an oxic/anoxic cycling strategy at intervals of 160 minutes on, 45 minutes off. Only the NH4-N content of the effluent was tracked.

A remote monitoring tool, AqScan, recorded and displayed all the online measurements generated by the multiple probes

(measuring dissolved oxygen [DO], pH, redox, NH4-N, NO3-N, temperature, and flow) and actuators. In addition, AqScan automatically estimates the oxygen uptake rate (OUR), oxygen transfer coefficient (KLa), and oxygen transfer efficiency.

A mathematical biological model-based simulator was developed using the WEST® modeling platform. The biological model is a modified ASM1 model extended to include inorganic particulate compounds and temperature variation prediction, which is crucial for

industrial compact treatment solutions. The model would help aid design enhancements to the existing basic DO control scheme to incorporate other process variables, such as NH4-N and NO3 -N concentrations and the inflow rate.

Promising Results Figure 2 shows the influent characteristics and the reactor’s mixed liquor total and Continued on page 32

Figure 2. Influent characteristics and reactor solids states.

Figure 3. Online measurements compared to lab measurements and oxygen uptake rate estimates.

Florida Water Resources Journal • June 2016

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Continued from page 31 volatile suspended solids measured during the study. The results suggested reducing mixed liquor total suspended solids in the bioreactor to around 6000 mg/L. The first two months were dedicated to trial runs at the plant to observe the immediate response of the process to a variation in critical process parameters. By the third month, the automatic control strategy designed was applied and maintained until the end.

The effect of the cyclic operating strategy was clear. On-line oxygen uptake rate (OUR) estimations indicated that OUR is maintained at 120–140 g/m3•d throughout both the oxic and anoxic phases. The oxygen demand in the anoxic phase is ostensibly met by denitrification of nitrates. Figure 3 shows the system’s response during the study period and Figure 4

shows this effect in detail (during three days of operation).

Table 1 summarizes the different operational strategies applied to the full-scale plant.

The HPO-MBR process was retrofitted for nitrogen removal using the oxic/anoxic cycles in the same compact reactor, providing more efficient nitrogen removal and energy savings.

The final strategy (validated at the fullscale plant) is as follows: 1. If the inflow rate is higher than 0: 120 minutes anoxic, 60 minutes oxic 2. If the inflow rate is 0 (no feeding): 60 minutes anoxic, 90 minutes oxic 3. If the inflow rate changes from 0 to another value: switch directly to anoxic operation 4. If the inflow rate changes from a value to 0: switch directly to oxic operation

Table 1. Summary of the results at the full-scale facility.

This study demonstrated that the AC process requires only minimal, if any, additional capital or infrastructural upgrades, making it a cost-effective solution to reach nutrient removal goals. The development of a calibrated biological process model and control strategies for optimizing the AC process will enable more robust and cost-effective implementation of the treatment process at this facility.

Note: The information provided in this article is designed to be educational. It is not intended to provide any type of professional advice including, without limitation, legal, accounting, or engineering. Your use of the information provided here is voluntary and should be based on your own evaluation and analysis of its accuracy, appropriateness for your use, and any potential risks of using the information. The Water Environment Federation (WEF), author and publisher of this article, assumes no liability of any kind with respect to the accuracy or completeness of the contents and specifically disclaims any implied warranties of merchantability or fitness of use for a particular purpose. Any references included are provided for informational purposes only and do not constitute endorsement of any sources.

Mónica de Gracia is a process engineer at the Hernani, Spain, office of Praxair Inc. Randall Marx is a development specialist and Rafael García is a global market development manager at the Burr Ridge, Ill., office of Praxair.

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Figure 4. Nitrogen after three days of intermittent oxygenation.

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Florida Water Resources Journal • June 2016

33

Toxicity SmackDown Joe Squitieri

Toxicity Issues

Hillsborough County Public Utilities Department (HCPUD) owns and operates eight wastewater treatment facilities (WWTFs) with a combined capacity of 62.1 mil gal per day (mgd) annual average daily flow (AADF) in the unincorporated areas surrounding Tampa. All of the facilities produce high-quality reclaimed water for public access reuse, and seven also meet advanced wastewater treatment (AWT) standards for surface water discharge. The seven facilities with a surface water discharge permit have limits for fresh water toxicity through acute or chronic testing, or a combination of both depending on the season. The inhibition concentration of less than 25 percent (IC-25) must be achieved to be considered a passing chronic test, which means there must be less than a 25 percent difference between the control and the test effluent for survival, growth, and reproduction.

The 12-mgd Falkenburg Road Advanced Wastewater Treatment Facility (AWWTF) sits to the south of the resource recovery facility and supplies about 1 mgd of reclaimed water to the facility for cooling and treats the upcyclewd water. Both sit behind the county building where the environmental services section is housed.

The AWWTF has had intermittent chronic toxicity for Ceriodaphnia dubia reproduction since late 2009. The Pimephales promelas portion of the test never failed, so it was never an issue. The facility currently uses fermentation basins and oxidation ditches to meet AWT limits and an ultraviolet light disinfection system (UVDS) for high-level disinfection. Due to three bioassay failures within a 12-month period, a corrective action plan (CAP) was required. On June 30, 2010, the CAP was approved by the Florida Department of Environmental Protection (FDEP) and implementation began.

The 2010 CAP focused on increased biomonitoring, sampling for broad-range water quality parameters, and comparing bioassay data between two facilities, one using a UVDS and the other using chlorine for disinfection.

Despite running numerous bioassays and over 3244 analytical tests, no definitive source of toxicity was found. However, in 2011 the facility managed to pass four routine chronic tests and the CAP was terminated.

Unfortunately, in 2012, the toxicity failures returned and by June 2013, another CAP was required. A consulting engineering firm was hired to review existing data, chemical

34 June 2016 • Florida Water Resources Journal

usage, industrial users, hauled wastewater, and facility performance and operations. When nothing definitive was found in phase I of the CAP, the recommendation was to conduct a toxicity identification evaluation and a toxicity reduction evaluation (TIE/TRE), an expensive and time-consuming proposition sanctioned by the U.S. Environmental Protection Agency (EPA).

Additional Investigation Prior to proceeding with the TIE/TRE, staff in the environmental services section of HCPUD, which includes the industrial pretreatment program (IPP), submitted a request to FDEP to delay implementation of the TIE/TRE so that an internal review of the data and information could be completed, sample collection methodology examined, process controls tightened, and additional samples collected while running monthly bioassays for C. dubia.

With the extension granted, the IPP team reviewed the safety data sheets (SDS) for the industries regulated by the program and found that a chemical used as a microbiocide in the cooling towers at the adjacent resource recovery facility (RRF) contained the following warnings: “This pesticide is toxic to fish and

wildlife” and “Do not discharge effluent containing this product to the sewer systems without previously notifying the local sewage treatment plant authority.” Each day, the RRF takes about 1 mgd of reclaimed water from the AWWTF for use in the cooling towers and returns about 0.17 mgd of spent cooling water to the headworks of the facility. It did not seem likely to most parties involved that the microbiocide could be the cause of the toxicity problem, especially since only about 7 gal of the product were used and it was diluted by more than 9 mgd of wastewater.

Typically, the microbiocide was applied on a Saturday night, cycled through the towers, and released on Sunday; sampling for the bioassay always started early Sunday morning.

The IPP staff requested the dates the product was used and compared it to the dates of the toxicity failures. Of the twelve bioassays run while the microbiocide was applied, nine failed. Of the three that passed when the biocide was used, one literally passed by a single C. dubia offspring (data results are tabulated in Table 1).

Although it appeared the IPP team was on the right trail, confirmation was needed. A request was made to FDEP to allow short-term “selective testing,” which involved RRF staff using the microbiocide outside of scheduled monthly bioassays. Of the nine bioassays conducted during this test period, eight passed.

The one failure could not be attributed to other activities, and the two additional tests passed.

Table 1. Falkenburg AWWTF Bioassay Test Results

Resolution Earlier in the course of the internal investigation, IPP staff and the plant operations group, which are responsible for the operation and maintenance of the facilities, met to brainstorm about the toxicity problem. One of the licensed operators who had been stationed at the facility for many years indicated that there were no toxicity failures prior to switching the disinfection process from chlorine to UV, but the process had changed in 2008. The notion that chlorine somehow mitigated the unknown toxicant was tested by running bioassays on effluent subject to varying levels of chlorine and then dechlorinated. Results reflected a linear dose response on C. dubia reproduction with increasing levels of chlorination, and that as little as 0.35 mg/L chlorine residual mitigated the toxic effect in the effluent. In one side-byside test, the sample aliquot disinfected through the UVDS failed with an IC-25 of 32.7 percent (well short of 75 percent), while all levels of chlorination passed. The SDS for the microbiocide appeared to indicate that its effect was hampered by strong oxidants, such as chlorine.

With this data in hand, IPP and RRF staff met and developed a control protocol intended to mitigate the toxic effects of the microbiocide through chlorination in the holding basin of the cooling towers. Specifically, after using the microbiocide, the water in the holding basin would be chlorinated to 0.5 mg/L, then held for a minimum of one hour prior to release to the sanitary sewer. This protocol and monitoring of the microbiocide and chlorine residual were then incorporated into a new industrial user permit for the RRF issued by the IPP team.

In 2015, bioassay testing was scheduled to coincide with the application of the microbiocide and implementation of the control protocol. Three routine bioassay tests were conducted and all passed. An additional routine bioassay test was run when the microbiocide was not used, and by January 2016, the AWWTF had

passed four routine chronic bioassays. A request was made to FDEP to close the CAP and in March 2016, FDEP issued a letter terminating it.

Through diligent efforts, trust in the data, and an open, cooperative attitude among interdepartmental staff, the issue of intermittent toxicity at the AWWTF was smacked down.

Joe Squitieri worked in the Southwest District of FDEP for many years before becoming the manager of the industrial pretreatment program for Hillsborough County Public Utilities Department in 2013.

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Nutrient Recovery From Municipal Wastewater Treatment Plants: Status and Prospects Hamidreza Sharifan Wastewater often contains valuable essential nutrients, such as nitrogen and phosphorus, contributing to eutrophication within receiving waters, as well as slowing the movement of river systems [1-4]. Eutrophication is a serious environmental issue worldwide [5]. A recent statistical report indicates approximately 48 percent of lakes and reservoirs in North America, 54 percent in Asia and the Pacific, 53 percent in Europe, and 41 percent in South America are suffering from this phenomenon [2].

The nutrients in wastewater are considered to be a remarkable food and energy source all around the world [6, 7]. In addition, they can be found in other sources, such as swine wastewater, runoff, and infiltration from animal feedlots, construction sites, and mines [3].

The typical concentration of organic matter in municipal wastewaters can be explained by 400to 500-mg chemical oxygen demand (COD)/L, which potentially equals to energy production of 1.5–1.9 kilowatt-hours (kWh) per volume of wastewater (m3). Energy collected from wastewater treatment is more than twice as high as the energy demanded for operation of a conventional activated sludge system. The aerobic mineralization of the sewage organic matter to carbon dioxide (CO2)

in conventional activated sludge can significantly cause the loss of energy [8]; recovery deficiency of nitrogen and phosphorus is another drawback.

Also, the energy recovery from the organic pollutants is very limited [8].

The conventional technique for nitrogen removal is the nitrification/denitrification process.

Chemical and/or biological processes are typically used for the removal of phosphorus from wastewater streams [8, 9]. Nitrogen and phosphorus removal processes significantly increase the volume of the reactor and consume energy up to 80 percent [9]. Particularly, mineral compounds of phosphorus that originate from mines may became scarce in the future [8].

Phosphorus is an essential and vital element in the biological structure of all organisms. It is also a key component in the body of deoxyribonucleic acid (DNA) and adenosine triphosphate (ATP) as an energy supplier, which cannot be substituted by any other element [10]. This explains why there is increasing research on the recycle and recovery of phosphor in wastewater.

Urinal wastewater contains approximately 94 percent of nitrogen, phosphorus, and potassium [11], as well as 50 to 90 percent of other major agricultural nutrients. Therefore, nutrient recovery and recycling from the urinal wastewater can maximize the number of nutrients and energy [9, 11].

Figure 1. Electrical Energy Demands for Different Nutrient Removal Processes

36 June 2016 • Florida Water Resources Journal

Consequently, it reduces the eutrophication in freshwater and coastal ecosystems [11].

Human urine as a multicomposition solution contains sodium chloride (NaCl) and the dominant compounds of urea (CO[NH2]2), as well as low concentration of calcium (Ca), potassium (K), sulfate (SO4), and phosphate (PO4).

Struvite (Mg[NH4][PO4]•6H2O) is one of the most important mineral compounds that can emanate from human urine [11]. It can be produced with relatively simple technology and it is applicable in removal and recovery of nitrogen from wastewater [12].

A reaction of ammonical phosphate solutions with magnesium can form struvite. Since human urine contains considerable amounts of ammonium relative to phosphate, but in a magnesiumdeficient amount, it needs an addition of magnesium oxide (MgO) [12], magnesium chloride (MgCl2•H2O), seawater, or bittern [13]. Also, by increasing the normal pH of human urine (5.6-6.8) [11] to optimum pH ( 9.5-10.5) [14], the phosphate forms ( H2PO−4 or HPO2−4) can shift the equilibrium toward PO3−4 for the struvite crystallization [11]. However, the efficiency of the process may improve by increasing the molar ratio of magnesium/phosphorus (Mg/P) up to 1.4 [14].

This method may be applicable for phosphate removal, but the spontaneous process with precipitation of struvite may cause operational problems in sewage systems [11]. Figure 1 shows the required energy for the extraction of nitrogen and phosphorus in each process (conventional and nonconventional); data are extrapolated from Mauer et al, (2003) [9]. As described, the extraction process of nitrogen and phosphorus through urine separation required less energy than the conventional process. Rather than food production through struvite, it could be used in broader applications, such as the flower industry, animal feed production, and production of starch source plants [12].

Another efficient method to recover nitrogen and phosphorus from wastewater takes place within microalgae [4, 15]. These autotrophic organisms produce the algal biomass, with light as their energy source. A combination of heterotrophic organisms and biofilms of microalgae can be efficiently used for two processes of nutrients immobilization and removal of COD; therefore, this system is called a combined treatment or symbiotic microalgae system [8].

Algae, or specifically green unicellular microalgae, have been investigated as a potential re-

newable fuel source [4]. Moreover, some microalgae species have shown a high removal rate for nitrogen by 96 percent, and 99 percent for phosphorus [16]. Interestingly, microalgae have a higher biomass productivity compared to plant crops regarding required farmland area and lower cost per yield, and it cuts the emission rate of greenhouse gases as a substitute for fossil fuels [15].

However, cultivation of microalgae is developing, and so far it has not demonstrated a cost-effective process at large scales [4].

trogen from industrial wastewater treatment as struvite slow releasing fertilizer." Desalination, 2007. 214(1): p. 200-214.

13. Lee, S.I. et al. "Removal of nitrogen and phosphate from wastewater by addition of bittern."

Chemosphere, 2003. 51(4): p. 265-271.

14. Song, Y. et al. "Nutrients removal and recovery by crystallization of magnesium ammonium phosphate from synthetic swine wastewater."

Chemosphere, 2007. 69(2): p. 319-324.

15. Pittman, J.K., A.P. Dean, and O. Osundeko.

"The potential of sustainable algal biofuel pro-

duction using wastewater resources." Bioresource technology, 2011. 102(1): p. 17-25.

16. Caporgno, M.P. et al. "Microalgae cultivation in urban wastewater: Nutrient removal and biomass production for biodiesel and methane." Algal Research, 2015. 10: p. 232239.

Hamidreza Sharifan is a research assistant in the department of civil, environmental, and construction engineering at Texas Tech University in Lubbock, Texas.

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References 1. Jaffer, Y. et al. "Potential phosphorus recovery by struvite formation." Water Research, 2002.

36(7): p. 1834-1842.

2. Cai, T., S.Y. Park, and Y. L. "Nutrient recovery from wastewater streams by microalgae: status and prospects." Renewable and Sustainable Energy Reviews, 2013. 19: p. 360-369.

3. Kumar, R. and P. Pal. "Assessing the feasibility of N and P recovery by struvite precipitation from nutrient-rich wastewater: a review." Environmental Science and Pollution Research, 2015. 22(22): p. 17453-17464.

4. Ge, S. and P. Champagne. "Nutrient removal, microalgal biomass growth, harvesting and lipid yield in response to centrate wastewater loadings." Water Research, 2016. 88: p. 604-612.

5. Yan, H.Y. et al. "Spatial and temporal relation rule acquisition of eutrophication in Da’ning River based on rough set theory." Ecological Indicators, 2016. 66: p. 180-189.

6. McCarty, P.L., J. Bae, and J. Kim. "Domestic wastewater treatment as a net energy producer– can this be achieved?" Environmental Science & Technology, 2011. 45(17): p. 7100-7106.

7. Gao, F., et al."Continuous microalgae cultivation in aquaculture wastewater by a membrane photobioreactor for biomass production and nutrients removal." Ecological Engineering, 2016. 92: p. 55-61.

8. Khiewwijit, R. et al. "Energy and nutrient recovery for municipal wastewater treatment: How to design a feasible plant layout." Environmental Modelling & Software, 2015. 68: p.

156-165.

9. Maurer, M., P. Schwegler, and T.A. Larsen. "Nutrients in urine: energetic aspects of removal and recovery." From Nutrient Removal to Recovery, 2003. 48(1): p. 37-46.

10. Cornel, P. and C. Schaum. "Phosphorus recovery from wastewater: needs, technologies and costs." Water Science & Technology, 2009.

59(6).

11. Lind, B.-B., Z. Ban, and S. Bydén. "Nutrient recovery from human urine by struvite crystallization with ammonia adsorption on zeolite and wollastonite." Bioresource Technology, 2000. 73(2): p. 169-174.

12. El Diwani, G. et al. "Recovery of ammonia niFlorida Water Resources Journal • June 2016

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FSAWWA SPEAKING OUT

Total Water Solutions®: What Does It Mean to Florida’s Utilities?

Kim Kunihiro Chair, FSAWWA

he FSAWWA board of governors recently met to develop our five-year strategic plan. Some of the top priorities include finding opportunities for young professionals to make a difference in FSAWWA as water professionals and also to embrace and develop the concept of Total Water Solutions®.

These priorities fit well together as FSAWWA’s young professionals are actively engaged and interested in the concepts of sustainability and reuse and the beneficial use of water resources.

Through the Total Water Solutions® concept, AWWA supports and promotes the integrated use of water resources, planning processes, and management practices that provide for reliable, sustainable, and cost-effective supplies of the most appropriate quality water for the proper use.

As fresh water resources are impacted by natural and human stresses, including climate variability, drought, and pollution or irresponsible consumption, it is imperative that we, as water professionals, begin to work together to ensure water resources and system reliability. The droughts in Texas and California demonstrate that the water that we take for granted here in Florida, where it rains more than 50 inches per year, can be adversely impacted over time. In stark contrast to the drought, Texas has recently experienced significant flooding from drastic rainfall in short intervals. Lives were lost and the impact to water resources has yet to be determined. How small

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and large utilities will be impacted is not yet known, but it may be quite drastic when sewer system overflows and other types of pollution are considered.

In the U.S. Environmental Protection Agency (EPA) 2014-2018 strategic plan for water, published on April 10, 2014, EPA outlined a plan to: S Provide financial assistance to small utilities for infrastructure development.

S Protect drinking water sources from contamination and also temperature increases due to climate change.

S Develop new drinking water standards.

S Promote robust planning that includes green and sustainable alternatives.

S Work with municipalities on implementing integrated planning for wastewater and stormwater management.

S Work to reduce and control pollutants from industrial, municipal, agricultural, and stormwater sources and vessels.

S Implement programs to prevent and reduce pollution that washes off land during rain events.

S Restore water bodies that do not meet water quality standards.

S Preserve high-quality water resources.

S Coordinate Clean Water Act and United States Department of Agriculture Farm Bill funds to protect water quality from runoff from agricultural lands.

S Lead efforts to restore and protect aquatic ecosystems, including the south Florida ecosystem.

In addition to all of these priorities, nutrient pollution is cited as the most significant concern for the nation’s surface waters.

This long-range and integrated approach to water resource management, Total Water Solutions® is not new to Florida. The water

FloridaSection 38 June 2016 • Florida Water Resources Journal

management districts (WMDs) and the Florida Department of Environmental Protection (FDEP) are tasked with this mission in water supply planning. A 2013 document provides water quality monitoring guidance, which emphasizes the importance of coordination between FDEP and the WMDs in order to protect water resources and gather the best available data to make informed water management decisions. Additionally, this can reduce the burden on utilities as they collect data for permits and compliance, but minimize duplicative data collection. Additionally, there is an effort to increase electronic reporting, which is a more sustainable and environmentally friendly approach.

A recent example of a report that may further an integrated approach to water resources management is the Report on Expansion of Beneficial Use of Reclaimed Water, Stormwater, and Excess Surface Water (Senate Bill 536), published Dec. 1, 2015. The purpose of the report was to conduct a comprehensive study to determine how the use of reclaimed water, stormwater, and excess surface water could be expanded to help meet future water demands as required by SB536. For many years, Florida has been a leader in water reuse and has expanded the use of reclaimed water from public access irrigation to include industrial uses, including cooling towers, agricultural irrigation, and groundwater recharge. The concept of indirect and direct potable reuse is considered in the report and the impediments to developing these projects in Florida are included.

A similar analysis was made for expanding uses of stormwater and excess surface water. Rather than just directing stormwater to a pond or surface impoundment to protect properties from flooding and to eventually percolate into the ground, alternatives were considered. These alternatives include an inte-

grated approach as agricultural land is developed and land use changes. Capturing available stormwater for water supply, particularly to support conjunctive use projects, may be effective, but it can be expected to have varying levels of reliability, depending on storage and climatic conditions.

Expanding the use of surface water for potable use continues to be considered by the WMDs in each water supply planning effort.

Constraints include environmental needs, seasonality of supply, and storage requirements.

Storage options could include aboveground reservoirs or aquifer storage and recovery. Each of these options includes the use of these resources for potable supplies or for uses where lower-quality water may be appropriate, making the Floridan aquifer and groundwater last longer for potable supply.

This report and the other examples cited show that the concepts of Total Water Solutions® and integrated water resource planning are not new and are being applied in Florida. It hits on several of the priorities in the EPA strategic plan. It is embodied in the work of FDEP and the WMDs and is consistent with the concepts of sustainability and maintaining the resiliency of water resources in our state for years to come.

I encourage you to read the report and to join FSAWWA’s Water Quality and Resources Division or the AWWA Water Resources Sustainability Division. Also available is the M50 Manual of Practice on Water Resource Planning, published by AWWA. This manual provides best practices and guidance to advance technical proficiency, institutional practices, and public policy to advocate for sustainable development, and protection and management of water resources for use as public supply.

These are concepts that both young professionals and seasoned professionals can embrace and support.

References • USEPA releases 2014-2018 strategic plan for water; Julia Jennison and Wayne E. Flower.

Journal AWWA, October 2014.

• Total Water Solutions: Integrated Water Resource Planning; William Y. Davis, Chi Ho Sham, Thomas E. Dumm, and Lara Kammereck. Journal AWWA, May 2016.

• Report on Expansion of Beneficial Use of Reclaimed Water, Stormwater and Excess Surface Water (Senate Bill 536); Office of Water Policy, Florida Department of Environmental Protection, Dec. 1, 2015.

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News Products The Husky 1050HP from Graco is the first pump on the market that allows users to choose between low-pressure and high-pressure operating modes with a low-high pressure mode valve. High-pressure operation isn’t always required, so the pump can be switched to the low-pressure mode to reduce air consumption up to 50 percent. These features, combined with the standard Husky diaphragm pump design; make this one of the most unique high-pressure diaphragm pumps on the market. Other features of the pump include: increased fluid pressure without sacrificing flow; low-high pressure mode valve to operate the pump as a standard air-operated double diaphragm (AODD) or a high-pressure AODD; same repair parts as the Husky 1050 AODD pump reduces inventory levels; and filter press, ceramic, high-head pressure or long -distance application areas. (www.graco.com)

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A powerful new high-efficiency aerator designed to provide maximum aeration while using only a fraction of the energy required by other models has been introduced by Airmaster Aerator. The new aerator, the 50 HP Turbo X-Treme Magnum, is a highefficiency, floating/surface aerator that can pump 12.5 mil gal of water per day. Powered by an energy-saving 50-HP motor, it incorporates a turbo blower and a double-sided impeller to achieve high-capacity water movement with maximum aeration and mixing. (www.airmasteraerator.com)

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The VAC-A-TEE® Trenchless Cleanout System from LMK Technologies now meets the newly published ASTM F3097-15 Standard, which is a standard practice for installation of an outside sewer service cleanout through a minimally invasive small bore created by a vacuum excavator. The process begins with locating the service lateral pipe by use of a locatable sewer camera that is robotically launched from the main pipe. Once the lateral pipe is exposed, a selfclamping saddle is prepared with a special adhesive and lowered into the small diameter bore hole until it contacts the lateral sewer service pipe. (www.lmktechnologies.com)

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The PermaNet+ and Pegasus+ water network monitors are now available from FCS. The Permanet+ provides remote monitoring and correlation of leaks in water distribution networks. Acoustic sensors attach magnetically to water pipelines, “listen” for leak noise, and use existing cellular networks to transfer findings to the cloud, with no need for additional repeating infrastructure. Utility personnel can then analyze leak noise audio and eliminate false positives from the office, conserving fuel and worker time on site visits. As part of the FCS OmniColl remote asset monitoring platform, PermaNet+ displays the reported leak data on a geographical overlay and exports the data for immediate remote correlation with one click.

Pegasus+ allows detailed, multipoint control for pressure reducing valves (PRVs) without a flowmeter. The controller analyzes data from up to three critical points (CPs) to automatically adapt to network changes and events, controlling PRV output pressure to maintain CP targets defined in terms of time, flow, or a combination of the two. A latching solenoid enables valves to be fully opened or closed in emergency settings. Pegasus+ can provide control over a network from any web-enabled device. (www.fluidconservation.com)

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The Water Eater® wastewater evaporator from Equipment Manufacturing Corp. has been engineered to efficiently evaporate the water content from many noncombustible wastewater sources. A power exhaust system releases the moisture into the air, leaving only a small residue requiring disposal. This massive reduction in the volume of liquids requiring disposal not only slashes disposal costs, but also economizes by reducing storage area requirements, labor and time for handling, and frequency of disposals. Evaporation rates range from 5 to 40 gal per hour. An optional auto-fill system automates the process and allows for 24-hour operation. The evaporator, available in gas or electric-heated models, has been designed to operate simply and efficiently, is installed easily, and is constructed of quality materials and equipment to assure trouble-free operation and long-life service. (www.equipmentmanufacturing.com) S

Florida Water Resources Journal • June 2016

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FWEA FOCUS

Standing on the Shoulders of Giants Lisa Prieto President, FWEA hen I began to think about this upcoming year of FWEA and our 75th anniversary, a theme popped into my head: “Standing on the Shoulders of Giants.” This was the theme we picked for my senior yearbook; we felt so blessed to have so many great teachers and classmates, and we thought it was a fitting way to commemorate our year.

I have similar sentiments now as I begin my year at the helm of FWEA. I think about the great mentors I have had over the years—those who encouraged me to get involved when I began working, who have taught me about the industry, and who continue to coach, support, and mentor me. On a broader scale, I think about those who started what is now FWEA 75 years ago, and those who have come before me. Each leadership team has grown and improved FWEA to get it to where it is today.

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Another group of “giants” I think about when I think of FWEA are the operators. These are the folks who carry out the hardest tasks in our industry day in and day out. If you have ever had the opportunity to work alongside an operator, you will quickly realize what dedicated, intelligent, and talented individuals they are. As designers, consultants, regulators, contractors, vendors, and managers, we may shape and form what needs to get done, but our work would never come to fruition without the day-to-day operations staff making it happen.

This year I want to strengthen the relationship between FWPCOA and FWEA; there is so much knowledge to be shared. Part of what I would like to accomplish this year is to hold joint events for members of both organizations. Brad Hayes has done a terrific job taking the Operators Challenge to the next level and I think there are even more opportunities to get more FWEA members involved in this great event.

There is also an opportunity for collaboration with FSAWWA. We have focused on the concept of “OneWater” over the last few years, but it’s

time to strengthen the bond. Both associations have common goals: protecting our environment, ensuring public health, and advancing our water industry. I look forward to working together as a team on joint events and further developing our membership and industries.

Last, but not least, I look forward to growing our membership—and not just in numbers, but in diversity. We would like to look for opportunities for members of the manufacturing community and its representatives to take a more active role in FWEA. The technology in our industry is constantly changing and our manufacturers and their representatives are a great source of information when it comes to learning about new equipment and technology.

We are actively looking for ideas and ways for this sector to share its knowledge, so please feel free to contact me with any ideas you may have.

I am honored to serve as president of FWEA this coming year and look forward to meeting our membership throughout the year.

If I can help in any way, please do not hesitate to contact me.

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Florida Section AWWA Delivers Doug Prentiss Sr.

Doug Prentiss Sr. is a member of the FWEA Safety Committee.

40 June 2016 • Florida Water Resources Journal

While attending the Great Chili Cook-Off at O’Leno State Park just outside High Springs, I saw this Florida Section AWWA outreach project (see photo). It was outfitted with drinking fountains, bottle fillers, and several other ingenious approaches to allow people to drink wonderful-tasting water.

What a fun and educational day for everyone who attended, including families. The entry fee was a can of food and a meal ticket was five dollars, and every penny went to the High Springs Clean-Up efforts.

In spite of dreary weather, the event was an absolute hit!

A great band played in a large pavilion and several other buildings housed children’s fun and educational activities.

The chili was good at every tent I stopped at (with various heat levels), and there were many secret ingredients in the entries, from spicy-hot to almost gumbo, which included pork and chicken. I don’t know who the contest winner was, but clearly everyone who tried the chili was smiling.

I was so proud to see the AWWA display, which reflected well on everyone who works so hard in the state to ensure safe drinking water. My congratulations to FSAWWA and the individuals who hauled this set-up out in the rain and storm, and made sure that every person who drank that water knew it was safe.

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Florida Water Resources Journal • June 2016

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Fighting the Baby Wipes War Hubert Colas One of the biggest challenges to successful wastewater management is the consumer. From gold fish to kitchen grease to pharmaceuticals, there is a long-held belief that disposing of something via the sewer system is an acceptable solution to the problem. And even as people become more conscious of the environment, many still throw objects away in the toilet.

The extra material in the system seems to be getting worse instead of better. One of the most vexing problems for wastewater management is baby wipes. Like any consumer product, companies have worked to expand beyond their original market. The $13.2 billion baby wipes market in the United States has expanded because it is now been marketed as a personal hygiene product and many packages say it is “flushable.” Instead of wipes being thrown out with diapers, they are going down the toilet.

The proliferation of baby wipes causes havoc in wastewater systems and is leading to major problems with processing.

Cities are battling “fatbergs,” which are a combination of fat globules, wet wipes, and other sanitary items that block sewers and cost millions of dollars to handle. Besides the impact on the infrastructure, it also requires significant human resources to clear such blockages. New York spent nearly $18 million in wipe-related equipment repairs in the last five years.

On the FluksAqua question-and-answer forum, which is designed for water and wastewater operators to share information among peers to promote solutions, the baby wipe

question comes up repeatedly. It is a common problem that affects both large and small facilities. One forum member asked how to overcome the problems of baby wipes in the wastewater network. The person posing the question recognizes that everyone is tackling the problem but wanted input on simple technical solutions, public awareness campaigns, and any actual numbers on the cost of baby wipes in the wastewater system.

42 June 2016 • Florida Water Resources Journal

Small Systems Issues One small community operator in

Washington State provides a detailed account of how baby wipes have made life difficult. The system’s finescreen is exposed and subjected to extreme cold and hot temperatures. When temperatures were high in the summer, the baby wipes would dry so fast inside the finescreen they would become extremely hard and create a clog on the screen.

In the winter, the wipes freeze and harden and cause clogs again. After unplugging the finescreen every few days for many months, the operator decided to remove it and rely on the barscreen. That created a new problem since the volume of baby wipes means it

needs to be manually cleaned at least once a day. The operator has budgeted for a sewer chewer to replace the finescreen since a local public awareness campaign has not impacted the flow of wipes.

Raising Public Awareness Efforts Several of the responses highlight a public awareness campaign as one tool to help stem the flow of baby wipes into the system.

When the packaging says flushable, people don’t know they are doing the wrong thing.

While not a perfect solution, there will be people who respond to being told not to flush the wipes, and it may reduce the number in the system. One responder said they had some good results with a mailer in the utility bill or local advertising.

Technical Solutions There is also a debate in the forum about the effectiveness of the N Impeller, which has blades that sweep solids out of the system.

The relief groove and guide pin in the volute pushs solids, such as rags, to be pumped away. It’s recommended by one operator, while another says it has challenges with small pumps. Another suggested a direct inline pump (DIP) system instead; with the feedback given, it seemed to work fairly well for baby wipes. The DIP lifts effluent directly at the point of entry, but one responder pointed out that there are still some issues to solve in order to ensure impermeability between the hydraulics and the motor to get the best performance.

Grinders are another solution, but storms can push pebbles into the system, which causes problems, and grinders can be cost-prohibitive in smaller communities.

Continued on page 44

Florida Water Resources Journal • June 2016

43

Continued on page 42

Do-it-Yourself Options While technical solutions are debated, there are some more local solutions that offer insight into the ingenuity of wastewater professionals.

One “MacGyver”-wannabe suggested creating a barbed-wire ball and placing it in a manhole upstream from the station. It can be tied to the cover and lowered into the invert so baby wipes get stuck to the ball. It can be pulled out and quickly detached using a snap hook. Ball replacement would depend on how much solid material is caught, and it still requires someone to physically go to the station to do the change.

The Challenge Continues Wastewater management is changing in how it deals with these new challenges to the sewer system. The waste that makes its way through the pipes has been impacted by how goods are marketed to consumers. The result is a struggle to maintain the integrity of the system while making expensive changes to cope with the influx of solid waste.

More education and industry action is needed to help reduce nonbiodegradable solids in the system. Several states have launched lawsuits against baby-wipe manufacturers that advertise their product as flushable. And some in the industry are working with manufacturers to create a wipe that actually is biodegradable. But, until more people are aware of the costs—from expensive repairs, as well as extended service stoppages—that simple square will continue to cause problems for the public, wastewater managers, and water systems globally, in both the short and long term.

Hubert Colas is President of the Americas at FluksAqua, a new online community dedicated to better water management.

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44 June 2016 • Florida Water Resources Journal

Certification Boulevard

This is my Farewell Edition of Certification Boulevard!

Just about 16 years ago, my friend, Gary ReVoir, called me and asked if I would be interested in being a committee member with him, and I said, “Sure, I’d love to.” We discussed developing a monthly column to run in the Florida Water Resources Journal to provide questions, answers, and explanations related to its theme.

So, in June 2000, we started our little column and called it “Certification Boulevard.”

Well, after nearly 2,000 questions, I’m tapped out! I think it’s time I say farewell, so this will be my last Certification Boulevard. I want to thank everyone for reading and providing feedback with your comments, suggestions, and compliments; I appreciate your time.

Roy Pelletier 1. What is one of the simplest forms of corrosion control in a water treatment plant? a. Increasing oxygen concentrations b. Cathodic protection c. Protective coating such as cement d. Stabilizing the water 2. Which digester, in a two-stage anaerobic digestion process, is normally not mixed and/or heated? a. Primary digester b. Secondary digester c. Neither are normally mixed or heated. d. Both are normally mixed and heated.

3. Which disinfectant will effectively kill Cryptosporidium, Giardia, protozoans, and some viruses? a. Chlorine b. Monochloramines c. Dichloramines d. Chlorine dioxide 4. What does the following formula represent?

OUR, mg/L/hr = mg/hr/gm TS, gm/L a. Oxygen uptake rate OUR) b. Specific oxygen utilization rate (SOUR) c. Sludge volume index (SVI) d. Fecal coliform

I would like to thank Gary ReVoir for reading and providing review comments on each column. Gary, your insight and experience has made Certification Boulevard a better column and I thank you so much for your valuable time and effort. I’d also like to thank the Journal folks, especially Rick Harmon, for the time and effort they put into making Certification Boulevard look good each month— thank you!

So, farewell, and keep reading the Journal; it provides useful and valuable information.

Thank you—I’ve had fun doing it!

–Roy

Test Your Knowledge of Various Water and Wastewater Operations Topics 5. What type of backflow condition can result if water distribution pressures are below atmospheric pressure, or at a negative pressure? a. Backpressure b. Backsiphonage c. Thermal expansion d. Conical flow 6. What are the two reaction-forming stages of anaerobic digestion? a. Foam and oxygen b. Acid and methane c. Volatile solids and total solids d. Nitrogen and methanol 7. What is the recommended minimum flushing velocity when flushing a water main? a. 1 ft per second (fps) b. 1.5 fps c. 2 fps d. 2.5 fps

10. What type of chlorine residual is attained after the breakpoint is achieved? a. Combined b. Total c. Free d. Mono Special thanks to Scott Ruland, water and wastewater manager for the City of Deltona, for providing the water-related questions.

Answers on page 54

LOOKING FOR ANSW E RS?

Check the Archives

8. What is the primary function of polymer conditioning in a belt filter press process? a. To decrease solids content. b. To promote rapid water release in the gravity section. c. To sterilize the microorganisms. d. To disinfect the sludge particles.

9. What condition will occur when unusually low pressures develop in a high-service pump? a. Cavitation b. Backflow c. Backpressure d. Backsiphonage

Are you new to the water and wastewater field? Want to boost your knowledge about topics youʼll face each day as a water/wastewater professional?

All past editions of Certification Boulevard through 2000 are available on the Florida Water Environment Associationʼs website at www.fwea.org. Click the “Site Map” button on the home page, then scroll down to the Certification Boulevard Archives, located below the Operations Research Committee.

Florida Water Resources Journal • June 2016

45

Operators: Take the CEU Challenge!

Members of the Florida Water & Pollution Control Association (FWPCOA) may earn continuing education units through the CEU Challenge! Answer the questions published on this page, based on the technical articles in this month’s issue. Circle the letter of each correct answer. There is only one correct answer to each question! Answer 80 percent of the questions on any article correctly to earn 0.1 CEU for your license. Retests are available.

This month’s editorial theme is, Biosolids Management and Bioenergy Production. Look above each set of questions to see if it is for water operators (DW), distribution system operators (DS), or wastewater operators (WW). Mail the completed page (or a photocopy) to: Florida Environmental Professionals Training, P.O. Box 33119, Palm Beach Gardens, FL 33420-3119.

Enclose $15 for each set of questions you choose to answer (make checks payable to FWPCOA). You MUST be an FWPCOA member before you can submit your answers!

Earn CEUs by answering questions from previous Journal issues!

Contact FWPCOA at membership@fwpcoa.org or at 561-840-0340.

Articles from past issues can be viewed on the Journal website, www.fwrj.com.

___________________________________ SUBSCRIBER NAME (please print)

Article 1 _________________________________ LICENSE NUMBER for Which CEUs Should Be Awarded

Article 2 _________________________________ LICENSE NUMBER for Which CEUs Should Be Awarded

If paying by credit card,fax to (561) 625-4858 providing the following information:

___________________________________ (Credit Card Number)

____________________________________ (Expiration Date)

Process Control Strategies for Biological Nutrient Removal in an Oxidation Ditch Ann Sager, Leslie Knapp, Sarina Ergas, and Gita Iranipour (Article 1: CEU = 0.1 WW)

1. Which of the following chemicals is used in the Falkenburg facility for additional phosphorus removal? a. Chlorine b. Activated carbon c. Ferric chloride d. Aluminum sulfate 2. The results of the sensitivity analysis show that the _____________ has the greatest influence on effluent ammonia concentrations. a. nitrite oxidizing bacteria maximum specific growth rate b. ammonia oxidizing bacteria maximum specific growth rate c. ordinary heterotrophic organism (OHO) maximum specific growth rate d. heterotrophic dissolved oxygen 3. Simultaneous nitrification-denitrification wastewater treatment systems typically feature a. relatively long mean cell retention times. b. consistently high dissolved oxygen concentration throughout the biomass. c. aeration equipment that creates uniform flow. d. unrestricted oxygen input.

4. At the Falkenburg facility, operators adjust mechanical aerator speed based on a. mixed liquor dissolve oxygen concentration. b. influent ammonia load. c. effluent nitrate concentration. d. influent carbonaceous biochemical oxygen demand (CBOD).

5. Which of the following is not listed as a way that this evaluation can be used to enhance operational efficiency? a. Miminizing waste activated sludge b. Flow pacing of phosphorus removal chemicals c. Reduced plant staffing d. Control of on-line aeration based on ammonia concentration

46 June 2016 • Florida Water Resources Journal

Cause-and-Effect Study of Biofermentation: A Novel Biosolids Residuals Point Source Reduction Technology Rob Whiteman and Brad Macek (Article 2: CEU = 0.1 WW)

1. The primary benefit of sidestream bioaugmentation is a. control over the growth of preacclimated microbes. b. easier than handling dangerous chemicals. c. the process is pre-approved by regulatory authorities. d. cost.

2. The challenge with extending mean cell residence time (MCRT) above 20 to 30 days is a. an excessively dense biomass is produced. b. oxygen requirements that often exceed the mechanical limits of plant equipment. c. development of excessive filamentous organisms. d. there is generally insufficient aeration basin volume.

3. Biochemical oxygen demand (BOD5) removal decreased by 0.06 percent in period ____ testing. a. 2 b. 3 c. 4 d. 5 4. The biofermentation model predicts that a municipal plant operating at a F/M ratio of 0.15 without a primary clarifier or biofermentation would produce ____ lb biosolids per lb of BOD5 removed. a. 0.2 b. 0.6 c. 0.15 d. 0.10 5. This evaluation revealed that secondary biosolids production is readily reduced when a. mean cell residence time (MCRT) is minimized. b. hydraulic retention time is within the plant’s design range. c. excess oxygen is applied. d. influent BOD5 is lowest.

ENGINEERING DIRECTORY

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Showcase Your Company in the Engineering or Equipment & Services Directory Contact Mike Delaney at

352-241-6006 ads@fwrj.com

Motor & Utility Services, LLC CEC Motor & Utility Services, LLC 1751 12th Street East Palmetto, FL. 34221 Phone - 941-845-1030 Fax – 941-845-1049 prademaker@cecmotoru.com • Motor & Pump Services Test Loaded up to 4000HP, 4160-Volts • Premier Distributor for Worldwide Hyundai Motors up to 35,000HP • Specialists in rebuilding motors, pumps, blowers, & drives • UL 508A Panel Shop, engineer/design/build/install/commission • Lift Station Rehabilitation Services, GC License # CGC1520078 • Predictive Maintenance Services, vibration, IR, oil sampling • Authorized Sales & Service for Aurora Vertical Hollow Shaft Motors

CLASSIFIEDS P os i ti on s Ava i l a b l e

Utilities Treatment Plant Operations Supervisor $55,452 - $78,026/yr.

City of Temple Terrace Technical work in the operation of a water treatment plant and auxiliary facilities on an assigned shift. Performs quality control lab tests and other analyses, monthly regulatory reports, and minor adjustments and repairs to plant equipment. Applicant must have State of Florida D.E.P. Class “A”, “B”, or “C” Drinking Water License at time of application. SALARY RANGES: $16.59 - $24.89 per hour • w/”C” Certificate $18.25 - $27.38 per hour • w/”B” Certificate (+10% above “C”) $20.08 - $30.12 per hour • w/”A” Certificate (+10% above “B”). Excellent benefits package. To apply and/or obtain more details contact City of Temple Terrace, Chief Plant Operator at (813) 506-6593 or Human Resources at (813) 506-6430 or visit www.templeterrace.com. EOE/DFWP.

Utilities System Operator II $37,152 - 52,279/yr.

Water-Reuse Distribution Supervisor $55,452 – 78,026/yr.

Utilities Engineering Inspector $52,279 - $73,561.90

Laboratory Manager $61,136 - $86,025/yr.

Apply Online At: http://pompanobeachfl.gov Open until filled.

Reiss Engineering, Inc. Are you looking for an opportunity with a company that is poised for growth? Reiss Engineering stands as one of the most prominent Civil and Environmental engineering firms in the State of Florida and the Bahamas.

Our main focus is water and wastewater, serving both public and private sector clients with integrity, technical excellence and a commitment to performance. At Reiss Engineering, we are committed to making success happen for our clients, our employees and our firm.

Reiss Engineering offers a competitive compensation and benefits package, as well as a stimulating and fast paced work environment. Reiss Engineering is continuously searching for highly talented individuals and welcomes resumes from those with an interest in joining our team. For a list of our current openings, or to submit a resume for a potential opportunity, please visit our website at www.reisseng.com.

Sarasota County A great place to live, work, and play!

Check out our Great Opportunities – www.scgov.net/careers (941) 861-5742 Tobacco Free/Drug Free Work Environment

Orange County, Florida is an employer of choice and is perennially recognized on the Orlando Sentinel’s list of the Top 100 Companies for Working Families. Orange County shines as a place to both live and work, with an abundance of world class golf courses, lakes, miles of trails and year-round sunshine - all with the sparkling backdrop of nightly fireworks from world-famous tourist attractions. Make Orange County Your Home for Life.

Orange County Utilities is one of the largest utility providers in Florida and has been recognized nationally and locally for outstanding operations, efficiencies, innovations, education programs and customer focus.

As one of the largest departments in Orange County Government, we provide water and wastewater services to over 500,000 citizens and 62 million annual guests; operate the largest publicly owned landfill in the state; and manage in excess of a billion dollars of infrastructure assets. Our focus is on excellent quality, customer service, sustainability, and a commitment to employee development. Join us to find more than a job – find a career.

We are currently looking for knowledgeable and motivated individuals to join our team, who take great pride in public service, aspire to create a lasting value within their community, and appreciate being immersed in meaningful work. We are currently recruiting actively for the following positions: Assistant Manager, Field Services $87,214– $112,133/ year Assistant Manager, Water Reclamation $73,611– $95,077/ year Environmental Management System Project Manager $69,118– $88,837/ year Engineer I, II, III $43,285– $81,557/ year Industrial Electrician I $36,733 – $48,464/ year Apply online at: http://www.ocfl.net/jobs.

Positions are open until filled.

Florida Water Resources Journal • June 2016

51

CITY OF WINTER GARDEN – POSITIONS AVAILABLE

Lee County Utilities Senior Engineer 03766OD $25.54-$46.41 hr depending on experience

The City of Winter Garden is currently accepting applications for the following positions:

Lee County Utilities in Southwest Florida is accepting applications for a Senior Engineer. This position is responsible for assignments requiring engineering assistance in the planning, coordination, execution and management of Water and Wastewater projects. For more information and to apply, please visit our web site http://agency.governmentjobs.com/leecounty/default.cfm contact ACyganiak@leegov.com

- Traffic Sign Technician - Water/Wastewater Plant Operator – Class C - Solid Waste Worker II - Collection Field Tech – I & II - Distribution Field Tech – I & II Please visit our website at www.cwgdn.com for complete job descriptions and to apply. Applications may be submitted online, in person or faxed to 407-877-2795.

City of Winter Garden - Senior Engineer The Sr. Engineer is involved in the planning, design, construction and inspection of streets, stormwater improvements, and water and wastewater utilities projects. Salary DOQ. The City of Winter Garden is an EOE/DFWP that encourages and promotes a diverse workforce. Please apply at http://www.cwgdn.com.

Minimum Qualifications : ~ Bachelor of Science in Civil Engineering ~ Florida PE license or ability to obtain license within 6 months of hire ~ 10 years of progressively responsible professional/administrative public works experience ~ Valid Florida driver's license ~ Thorough knowledge of stormwater and utility system design, construction, and maintenance; engineering design; drafting; computer aided drafting systems; and design software (i.e., Auto CAD, AdICPR, ASAD, Ponds, Hydraflow, Networx)

City of Winter Garden Construction Projects Manager The position acts as the City's project manager for all capital improvement construction projects including water, wastewater, roadways, parks, stormwater systems and other facilities; inspection of private development projects; and supervision of 3 construction inspectors. Salary DOQ. The City of Winter Garden is an EOE/DFWP that encourages and promotes a diverse workforce. Please apply at http://www.cwgdn.com.

Minimum Qualifications: ~ High school diploma or GED equivalent and two years of college coursework. ~ 10 years of field experience in utilities and/or structural construction management ~ Working knowledge of general construction of above and below ground utilities. ~ Valid driver's license

52 June 2016 • Florida Water Resources Journal

FOR EMPLOYMENT OPPORTUNITIES VISIT OUR WEBSITE AT: WWW.CASSELBERRY.ORG Job Title: Water Production Plant Operator I/II/III Salary: $31,899 – $55,500 (DOE and Certification) We offer a competitive compensation package and affordable health benefits. The City of Casselberry is an Equal Opportunity Employer. For additional information regarding responsibilities or qualifications and to apply, please visit our website.

Water Wastewater Project Manager Woodard & Curran, is seeking a Project Manager for our Inverness, FL facility, to oversee the day-to-day operation of a water and wastewater utility serving approximately 4,500 customers. The utility consists of a wastewater treatment plant, 33 lift stations, wastewater collection system, one water treatment facility with three wells, booster station, ground storage tank and the distribution system. The utility staff will be 10 to 12 employees to manage the system. The Project Manager will play an active role in the coordination and communication with City staff, contractors, vendors, engineers and the public to oversee the on-going daily operation of the utility system.

Polk County Government BOCC Capital Projects Manager (Utilities CIP) - Polk County BoCC Polk County BoCC is now hiring for a Capital Projects Manager at their Utilities Division. If you are a Civil or Environmental Engineer and are looking for a career change, please apply by clicking the link below: Career Link: Capital Projects Manager- Polk County BoCC- Career Portal.

Location: Winter Haven, FL 33880 Work Schedule: Monday - Friday 8am - 5pm Compensation: $66,830.40 – Commensurate with Experience Please feel free to also forward your resume to mfreitas@source2.com

City of St. Petersburg Water Resources Department - Senior Water Resources Managers City of St. Petersburg - Senior Water Resources Manager (2 positions: Water or Wastewater Division) (IRC#33840) Professional, management work directing the assigned division. Requirements: Extensive experience/knowledge of water or wastewater systems and the related laws/standards; Open Until 6/1/16; $84,068-$122,884 DOQ; See detailed requirements at www.stpete.org/jobs EEO-AA-Employer-Vet-DisabledDFWP-Vets' Pref

Project Manager Florida Aquastore, the premier company for the water storage and wastewater market across Florida, The Caribbean, Central and South America, is seeking a Project Manager for its Boca Raton office. This position requires the ability to manage multiple water and wastewater projects. The construction projects involve the design and construction of small to medium size wastewater treatment plants and bolted steel storage tanks.

The ideal candidate is preferably bilingual (English/Spanish) and have the ability to travel approximately 25% of the time to the Caribbean and Latin America.

Call Marcelo Sicuro at (561) 994-2400 Email: marcelo@florida-aquastore.com

Operator Trainee

Peninsula Engineering is seeking the following positions for various locations in Collier County.

Plant Operator Multiple positions including a Lead. Must have FDEP Class “C” dual licensure (or higher).

Plant Maintenance Mechanic Journeyman level position conducting preventative and corrective maintenance.

Both positions require a high school diploma/GED equivalency and a valid driver’s license. Send resume or inquiries to HR@barroncollier.com EOE/DFWP

“C” Water Plant Operator The City of Lake Mary is hiring a Class "C" Water Plant Operator. $31,158 - $48,651 with exc. benefits. Please visit www.lakemaryfl.com for the requirements, job description and to apply. EOE, V/P, DFWP

Electronic Technician The City of Melbourne, Florida is accepting applications for an Electronic Technician at our water treatment facility. Applicants must meet the following requirements: Associate’s degree from an accredited college or university in water technology, electronics technology, computer science, information technology, or related field. A minimum of four (4) years’ experience in the direct operation, maintenance, calibration, installation and repair of electrical, electronic equipment, and SCADA systems associated with a large water treatment facility. Experience must include field service support and repair of PLC’s, HMI, SCADA, programming VFD’s, switchgear and working in an industrial environment. Desk/design work does not count toward experience. Must possess and maintain a State of Florida Journeyman Electrician License. Must possess and maintain a valid State of Florida Driver's license. Applicants who possess an out of state driver’s license must obtain the Florida license within 10 days of employment.

Salary Range: $40,890.98 - $68,680.30/yr, plus full benefits package.

To apply please visit www.melbourneflorida.org/jobs and fill out an online application. The position is open until filled. The City of Melbourne is a Veteran's Preference /EOE/DFWP.

The City of Melbourne, Florida is accepting applications for an Operator Trainee at our water treatment facility. Applicants must meet the following requirements: High School diploma or G.E.D. General work experience related to the operation and maintenance of water treatment equipment or any equivalent combination of acceptable training, education, and experience. Must have successfully completed and passed the approved required training courses and have passed the State of Florida Class “C” Water Treatment Exam. Must possess a State of Florida Class “B” commercial driver’s license with air brake endorsement. Applicants who do not currently possess a Class “B” CDL, with air brake endorsement, must acquire a learner’s permit within 3 months of hire and obtain the license within 6 months of hire. Applicants, who possess an out of state driver’s license, must obtain a Florida license within 10 days of employment. Must have working knowledge of nomenclature of water treatment devices. A knowledge test will be given to all applicants whose applications meet all minimum requirements.

Salary Range: $33,360.60 - $53,331.72/yr, plus full benefits package.

To apply please visit www.melbourneflorida.org/jobs and fill out an online application. The position is open until filled. The City of Melbourne is a Veteran's Preference /EOE/DFWP.

P o s itio ns Av ailab l e JOSEPH BRANCATO, Jr. – Seeking a position in the Cross Connection industry preferably in the Palm Beach Gardens area. Master plumber, DEP and NEWWA certified backflow preventer tester and inspector. Extensive experience in testing, installation and repair of backflow preventers from ½” to 10” in size, both DCVA’s and RPZ’s. Referrals upon request. Contact at 6 Richardson Path, Newburyport, MA 01950. email: widner216@me.com 978-230-2558.

LOOKING FOR A JOB? The FWPCOA Job Placement Committee Can Help!

Contact Joan E. Stokes at 407-293-9465 or fax 407-293-9943 for more information.

Classified Advertising Rates - Classified ads are $20 per line for a 60 character line (including spaces and punctuation), $60 minimum. The price includes publication in both the magazine and our Web site. Short positions wanted ads are run one time for no charge and are subject to editing. ads@fwrj.com Florida Water Resources Journal • June 2016

53

Certification Boulevard Answer Key January 2016

Editorial Calendar January ....Wastewater Treatment February....Water Supply; Alternative Sources March........Energy Efficiency; Environmental Stewardship April ..........Conservation and Reuse May............Operations and Utilities Management; Florida Water Resources Conference June ..........Biosolids Management and Bioenergy Production July ..........Stormwater Management; Emerging Technologies; FWRC Review August ......Disinfection; Water Quality September Emerging Issues; Water Resources Management October ....New Facilities, Expansions, and Upgrades November..Water Treatment December..Distribution and Collection Technical articles are usually scheduled several months in advance and are due 60 days before the issue month (for example, January 1 for the March issue).

The closing date for display ad and directory card reservations, notices, announcements, upcoming events, and everything else including classified ads, is 30 days before the issue month (for example, September 1 for the October issue).

For further information on submittal requirements, guidelines for writers, advertising rates and conditions, and ad dimensions, as well as the most recent notices, announcements, and classified advertisements, go to www.fwrj.com or call 352-241-6006.

Display Advertiser Index Blue Planet ....................55 CEU Challenge ..............43 CROM ............................28 Data Flow ......................29 FSAWWA Exhibits ..........17 FSAWWA Call for Papers..18 FSAWWA Overview ........19 FSAWWA ACE ................25 FWPCOA Short School....21 FWPCOA Training ..........27

Garney ............................5 Hudson Pump ................33 ISA Symposium..............47 McKim & Creed..............37 Medora ..........................13 Stacon ............................2 UF Treeo ........................41 Vaughn ............................7 Xylem ............................56

54 June 2016 • Florida Water Resources Journal

From page 43 1. D) Stabilizing the water Stabilizing the water is often the simplest form of corrosion control. When stabilizing corrosive water, alkalinity is increased in the form of lime, soda ash, or caustic soda. The goal is to saturate or slightly supersaturate the water with calcium carbonate so that it is stable or slightly scale-forming. This will provide a protective coating on the interior of pipes.

2. B) Secondary digester Typically, the secondary digester in a two-stage anaerobic digestion process is not mixed or heated. This tank is typically used as a gas- and sludge-holding tank.

3. D) Chlorine dioxide Chlorine dioxide is the only disinfectant listed that will effectively kill Cryptosporidium, Giardia, protozoans, and some viruses. Chlorine dioxide is an extremely effective oxidizing agent and its use must be closely monitored.

The maximum residual disinfectant level (MRDL) for chlorine dioxide is 0.8 mg/L; the MRDL for chlorine and chloramines is 4.0 mg/L. Besides its ability to kill different organisms, chlorine dioxide does not react with organics to form trihalomethanes.

4. B) Specific Oxygen Utilization Rate (SOUR) The specific oxygen utilization rate, or SOUR, is calculated by dividing the oxygen uptake rate (OUR) test results by the total solids content of the sample in grams per liter. The SOUR is used to determine potential for additional volatile solids reduction that is remaining in a sample. Typically, the SOUR results of aerobically digested sludge should be no greater than 1.5 mg/hr/gm TS to meet Class B standards for vector attraction reduction.

5. B) Backsiphonage Backsiphonage is possible when distribution pressures are less than atmospheric pressure (14.7 psi at sea level) or when negative pressures develop. Backsiphonage is the reverse flow of water within a water supply system due to negative pressures in the pipe system, enabling atmospheric pressure to force the flow of water backwards through a siphon action.

6. B) Acid and methane The first reaction is when volatile solids in the feed sludge are converted to volatile acids; this is known as the acid phase of anaerobic digestion. The second reaction is when methane-forming bacteria use volatile acids and convert them into methane gas, carbon dioxide, water, and other trace gases.

Alkalinity is abundant as a result of the methane-forming phase. Anaerobic digestion is not complete until the second reaction of digestion takes place.

7. D) 2.5 fps The recommended minimum flushing velocity is 2.5 fps and velocities of 5 fps are preferred. This increase in velocity may remove deposits, sediment, and bio film. When flushing water mains it is important to not drop system pressure below 20 psi, which can cause backflow and possibly contaminate the distribution system.

8. B) To promote rapid water release in the gravity section.

The result of polymer conditioning of the feed sludge is a release of water in the gravity section of the belt filter press. This is accomplished by neutralizing the charge of the sludge, which allows bound water to be released and drained from the sludge slurry.

9. A) Cavitation Cavitation occurs when pressures drop inside a high-service pump that is in operation. This drop in pressure causes gas pockets to form in the water, which then collapse, causing severe damage to the pump’s interior. This can occur when a pump is trying to deliver more water than it was designed for, commonly called “pumping off the curve.” When this happens, there is a significant drop in pump efficiency, as well as damage to the pump.

10. C) Free Free chlorine residual is attained after all of the demand for chlorine has been satisfied, indicating that breakpoint has been achieved. Theoretically, after the breakpoint has been achieved, the total residual and the free residual will be basically the same value.