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Contents ISSN-0835-605X • Sept/Oct 2011 Vol. 24 No. 5 • Issued October 2011 Editor and Publisher STEVE DAVEY E-mail: steve@esemag.com Consulting Editor

TOM DAVEY

Sales Director PENNY DAVEY E-mail: penny@esemag.com

FEATURES

DEPARTMENTS

6

Product Showcase . . . . . . . . 71-75 Environmental News . . . . . 76-82 Professional Cards . . . . . . . . 76-81 Ad Index . . . . . . . . . . . . . . . . . . 82

Sales Representative DENISE SIMPSON E-mail: denise@esemag.com Accounting SANDRA DAVEY E-mail: sandra@esemag.com Circulation Manager DARLANN PASSFIELD E-mail: darlann@esemag.com Production Manager CHRIS MAC DONALD E-mail: chris@esemag.com

To compete, or not, compete - that is the question - ES&E readers add their voices

8

Portable flow meters solve town’s flow rate discrepancies

10 Abbotsford secures approval for a new drinking water source 12 WERF studies the fate of trace organics in wastewater treatment

Editorial Assistant PETER DAVEY

Technical Advisory Board Jim Bishop Stantec Consulting Ltd., Ontario Bill Borlase, P.Eng. City of Winnipeg, Manitoba Bill DeAngelis, P.Eng. Associated Engineering, Ontario Peter Laughton P.Eng. Consulting Engineer, Ontario Marie Meunier John Meunier Inc., Québec Peter J. Paine Environment Canada

14 New CSO treatment shaft technology replaces cancelled tunnel project - Cover Story 18 Ontario developing Best Management Practices for hydroelectric facilities 20 Improving the energy efficiency of pumping systems 22 How to design your own water treatment system 24 Evaluating household scale water systems for arsenic removal 28 Kenora installs new 3.4 km watermain under Lake of the Woods 34 How Canada’s largest airport co-exists with one of Toronto’s last green spaces 38 Global mining sector faces severe water management challenges 40 New MBR system eliminates sewer surcharges for snack food processing plant

Environmental Science & Engineering is a bi-monthly business publication of Environmental Science & Engineering Publications Inc. An all Canadian publication, ES&E provides authoritative editorial coverage of Canada's municipal and industrial environmental control systems and drinking water treatment and distribution. Readers include consulting engineers, industrial plant managers and engineers, key municipal, provincial and federal environmental officials, water and wastewater plant operators and contractors. Information contained in ES&E has been compiled from sources believed to be correct. ES&E cannot be responsible for the accuracy of articles or other editorial matter. Articles in this magazine are intended to provide information rather than give legal or other professional advice. Articles being submitted for review should be e-mailed to steve@esemag.com. Canadian Publications Mail Sales Second Class Mail Product Agreement No. 40065446 Registration No. 7750 Undeliverable copies, advertising space orders, copy, artwork, proofs, etc., should be sent to: Environmental Science & Engineering, 220 Industrial Pkwy. S., Unit 30, Aurora, Ontario, Canada, L4G 3V6, Tel: (905)727-4666, Fax: (905) 841-7271, Web site: www.esemag.com

42 New thermophilic digester commissioned at Vancouver’s Lions Gate WWTP 45 Water conservation and the new economy 47 Open source software reporting system developed for water and wastewater SCADA systems 50 SART technology coming of age for cyanide recycling 52 How metals and rare earth elements make everyday life possible 56 Bowen Island WWTP upgrade presented unique challenges 59 Edmonton’s airport upgrades its deicing fluid treatment system 64 Analyzing a complex oil spill at an Ottawa hospital 70 Alternative WWTP project delivery model is key to improving Mumbai’s quality of life

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Comment by Steve Davey

To compete, or not compete – that is the question n the Summer 2011 issue of ES&E, I paid homage to our wastewater plant operators, who play a vital role in running what are essentially $10-200 million 24/7 processing plants, that ensure both public health and environmental protection. Over the years, many of them have competed in Operations Challenges and have expressed to me the tremendous development that occurs while training for and competing in the events. In my mind, too many Canadian municipal managers don’t see the value in supporting their plant operators, who may want to compete. Many operators can only participate, in Operations Challenges, if they pick up their own expenses and take personal

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Dear Mr. Davey, In response to your Summer 2011 issue commentary: “To compete, or not compete – that is the question”, I would agree that “encouraging operators to exceed their current qualifications by supporting professional development events like Operations Challenges is money well spent.” At the Ontario Clean Water Agency (OCWA), we have definitely seen the benefits of encouraging employees to train for and compete in various Operations Challenges both on a local and international level. We feel strongly that the skills acquired while competing in these challenges serves to better prepare them for real field operations, especially in an industry where routine can quickly become not-so-routine and can impact health and safety. These challenges provide ample opportunities for team building, critical thinking, applied knowledge and experience. I’m proud to say that OCWA presently supports two Operations Challenge teams, the OCWA Jets and the Flangetastic Four, both of whom compete internationally and who were recently ranked #1 and # 2 respectively at the New Jersey Water Environment Association Spring Fling Invitational Operations Challenge. For the record, our OCWA employees did not have to cover their own expenses or use vacation time to attend the challenges. That said, we were pleased that our teams were motivated enough to train for these events during their own personal time. Thank you for extolling the benefits of participating in Operations Challenges – we only hope that more municipalities see 6 | September 2011

vacation time to attend. Some regional Canadian competitions, are now attracting only 3-4 teams, whereas they used to attract 15-17. Reader response to this situation has been encouraging and, with WEFTEC happening in October, we are pleased to publish comments from two organizations.

Steve Davey is Editor of ES&EMagazine. E-mail comments to steve@esemag.com

value in these competitions and help provide their operators with a platform to increase their knowledge and test their skills in a ‘safe’ environment. These acquired skills will serve to increase their capability as water and wastewater professionals. Jane Pagel, President and CEO, Ontario Clean Water Agency Dear Steve: I read your article "To compete or not compete - that is the question?". I appreciate the support you provide for the operators. Over the last several years, with increasing technological sophistication and the complexities of operating these facilities, it is often forgotten that the operators must continue to learn and develop their understanding of operations. Certification programs are the first step in ensuring our operators are well versed in their "trade". Programs, such as the Operation's Challenge Competition provide an avenue for operators to practice and focus their training and skills, as well as learn and share their knowledge with other operators who may be experiencing similar operational issues. This competition allows the operator good networking opportunities that will provide significant benefit to the efficiency and management of their facilities. As a past competitor in the Operation's Challenge, I can't tell you how important my networking with operator from other municipalities has been for my development as an operator. We frequently communicate as a group to troubleshoot problems in our plants. We share our experience, what works and what doesn't work.

Now, as a volunteer for the Professional Wastewater Operators (PWO), I hope to continue sharing my experience to help new operators develop and benefit from my experience. Rick Niesink Regional Municipality of Niagara PWO Chair for the Water Environment Association of Ontario (WEAO) Phosphorus is bad 70s science tells us so Causes macrophytes to flourish Deep sags in Dee Oh Trickling filters and membranes We try our very best Equipment suppliers are happy But the Ministry won’t let it rest Get it even lower Is what they always say Even after we tell ‘em There ain’t no other way In desperation we throw our hands up Then gaze at the manure pile Maybe the farmer can help us While getting funded all the while In the end the real solution May be to chase all the humans away Then maybe MOE will be happy Unless CCME has final say. -- Anon

Environmental Science & Engineering Magazine


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Instrumentation and Control

Portable flow meters solve town’s flow rate discrepancies aced with suspension of construction permits due to flow rate uncertainty, the Township of North Glengarry, Ontario, asked Greyline Instruments to help troubleshoot two permanently installed flow meters. A forcemain meter at the sewage pump station was reading five times higher than an open channel flow meter at a lagoon two km away. The Township needed to determine which of the two flow meters was reading incorrectly. Troubleshooting forcemain flow The first step was to evaluate performance of the sewage pump station’s 12” magmeter. The cost to remove it for calibration was prohibitive, so Greyline supplied a clamp-on PDFM 5.0 portable doppler flow meter to verify readings. The forcemain is fed by four pumps. In normal operation, only two pumps run at the same time. The two located closest to the wall of the wet well create severe turbulence at the ultrasonic sensor mounting location, so readings were erratic. But, results were conclusive when the other two pumps were operated. The portable flow meter readings corresponded exactly with the 30-32 gpm rate displayed by the station’s magmeter. Troubleshooting open channel flow The investigation shifted to the second site, two km from the pump station, where the forcemain discharged to an open channel and then to a sewage lagoon. An existing open channel flow meter had been measuring flow to the lagoon through a 24” rectangular weir. It was reading much lower than the pump station’s magmeter. To compare readings from the pump station magmeter and from the open channel flow meter, the Township needed

F

Portable doppler flowmeter installed in the pump station to verify readings.

Stingray level-velocity logger installed temporarily at the sewage lagoon.

sewage lagoon. The Stingray uses a submerged ultrasonic sensor mounted at the invert of the partially filled pipe to measure water level, velocity and temperature for flow calculation. A stainless steel bracket was installed in the invert of the

A forcemain meter at the sewage pump station was reading five times higher than an open channel flow meter at a lagoon two km away. a data logging flow monitor for temporary installation. So, a portable Greyline Stingray level-velocity logger was installed in a 16” pipe, between the rectangular weir and the discharge to the 8 | September 2011

pipe to secure the sealed ultrasonic sensor in position. The Stingray was operated for one month and logged data was downloaded to a computer and opened using Greyline

Logger software. Flow cycles from the pump station were clearly illustrated in the log file and showed that totals from the Stingray and magmeter corresponded within 1 gpm. Conclusion The portable doppler flow meter and the level-velocity logger both corresponded exactly with the pump station’s magmeter. By process of elimination, the Township concluded that the permanent open channel flow meter at the lagoon site was malfunctioning. It has since been repaired and put back in service. For more information, E-mail: ernie@greyline.com

Environmental Science & Engineering Magazine


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Water Supply

Abbotsford secures approval for a new drinking water source fter two years of detailed environmental assessment and hydrologic modeling, the British Columbia government has given its approval for a groundwater extraction project in the City of Abbotsford. The Bevan Avenue Wells project will provide a clean, reliable source of drinking water for Abbotsford and Mission over the next five years. Abbotsford is situated east of Vancouver in the Fraser Valley, a key agricultural region for the province and western Canada. Demands on water supply in this area are very high due to growing residential and commercial centres, as well as agricultural and industrial demands. Water is currently provided by the Abbotsford Mission Water & Sewer System (AMWSC), which supplies water to over 200,000 residential, commercial and industrial customers in the Fraser Valley. Water is primarily drawn from surface sources; the majority comes from Norrish

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Creek and a smaller supply comes from Canal Lake. Both of these sources are located on the north side of the Fraser River in mountain valleys near Mission, while Abbotsford is on the south side of the river. Population growth, combined with drought conditions in recent years, has made securing a larger supply of safe, clean, and reliable water a critical priority. AMWSC is exploring opportunities, but large water supply sources can take several years to develop. As an interim measure, the AMWSC will rely on groundwater from the Abbotsford-Sumas Aquifer. The threat of disruption to the distribution system from earthquakes and natural mountain hazards also demands that there be sufficient water supply for essential emergency services, such as fire fighting and hospitals. The aquifer is a logical source for this backup water supply. The Bevan Wells project Several groundwater well locations were explored across the aquifer. The AMWSC chose the Bevan Avenue site, where there are four existing low capacity wells. The site is at the corner of a municipal park within the urban core, and is immediately adjacent to existing water Environmental Science & Engineering Magazine


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Water Supply distribution infrastructure. This area of the aquifer can supply large volumes of water, and the easy access and existing infrastructure ensures the project will have minimal additional environmental impact on the surface. The four existing water wells will now be upgraded to increase their capacity by over 300 percent. Now that the Bevan Avenue Wells upgrade is moving forward, the system is prepared to tackle increased demand on the system, due to seasonal dry weather and unplanned outages in other parts of the water system. Environmental assessment Increasing the capacity of the Bevan Wells triggered the requirement for an environmental assessment (EA) under BC’s Environmental Assessment Act. The City hired Hemmera, an environmental consulting firm specializing in environmental assessment, and Piteau Associates, a hydrogeology firm. The aquifer supplies water to several surface creeks in the region. Extracting water from the aquifer will result in a temporary drawdown in the groundwater level underground, and this will temporarily reduce water available to feed

surface creeks. Piteau undertook a sophisticated numerical groundwater modeling exercise to predict the groundwater “zone of influence” resulting from operating the expanded Bevan Wells. Zone of influence refers to the area around the wells where the aquifer water level would be drawn down by more than 10 cm while the wells were operating. It was then used to predict which surface water creeks would have reduced flows. The areas of reduced surface water flows were then used to predict potential effects on fish, fish habitat, terrestrial vegetation and wildlife. The modeling exercise predicted that fish and fish habitat would be affected in two of the surface creeks, and this triggered the need for an approval from Fisheries and Oceans Canada. Hemmera secured this approval by developing innovative mitigation to ensure that fish and fish habitat are not impacted by the use of the Bevan Wells. When the Bevan Wells are in use, the City of Abbotsford will augment water flow in two creeks by drawing from two new nearby mitigation wells, using a sophisticated real-time monitoring system

that activates the mitigation wells, as soon as the creek flows fall below a threshold. Approval Hemmera’s role in preparing the EA application submissions included conducting environmental and social impact studies, developing mitigation, and liaising with local communities and First Nations. After a thorough review, the Environmental Assessment Offices (EAO) gave the project the green light, concluding that the project would have no significant environmental, social or health effects on the surrounding areas. Throughout the operational phase of the project, detailed monitoring programs will be carried out. This monitoring is a condition of EA approval, and will verify the predicted effects on groundwater, surface water, fish, and fish habitat. If the project causes some environmental effects that were not anticipated, Hemmera will work with AMWSC in adopting an “adaptive management” approach, to develop solutions. For more information, E-mail: sweston@hemmera.com

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Wastewater Treatment

WERF studies the fate of trace organics in wastewater treatment esearchers for a recently completed Water Environment Research Foundation project have identified key baseline information concerning the estrogenicity and concentrations of individual trace organic compounds during common wastewater treatment processes. The project is one of the first research efforts to look specifically at the fate of these compounds throughout the solids phase of treatment. Results shed new light on the occurrence, concentration, characteristics, and potency of estrogenic compounds that preferentially partition onto solids during common wastewater treatment processes. A multi-disciplinary team of experts collected samples at four full-scale wastewater treatment plants over two years. They calculated the amounts of trace organics and estrogenic activity for each sample point in the treatment process, enabling them to gauge their levels as they

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In recent years, it has become much easier to detect very small amounts of trace organic substances, such as those found in pharmaceutical products, that may have the potential to be biologically active at extremely low concentrations.

moved through the plants. The estrogenic activity is made up of steroidal hormones and synthetic estrogenic compounds. Out of the suite of 100 compounds measured, and based on the Model of Concentration Addition, nearly all of the

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estrogenicity in all plants and all dates was due to the presence of 16 compounds, namely the steroidal compounds (mainly estrange and estradiol) and the alkylphenols (mainly nonylphenol and short chain ethoxylates). The study reached a number of significant conclusions concerning estrogenicity throughout the wastewatewater treatment process: • For all plants, the total estrogenicity leaving the plant was less than that entering the plant. • The total estrogenicity leaving the plant in the biosolids generally was greater than that leaving the plant in the secondary treated effluent. • Aerobic digestion reduced estrogenicity. • Both mesophilic and thermophilic anaerobic digestion increased estrogenicity, as did lime stabilization. The research team attributed the increase in estrogenicity during anaerobic digestion processes to transformation of some of the compounds into a more estrogenically potent form. • Although the contribution to total estrogenicity by non-steroidal, synthetic compounds (e.g., alkylphenols) varied from plant to plant, the results indicate they can be a major contributor and cannot be ignored in favor of only focusing on steroidal hormones. For more information, visit www.werf.org

Environmental Science & Engineering Magazine


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www.esemag.com

September 2011 | 13


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Stormwater Management

New CSO treatment shaft technology replaces cancelled tunnel project By Kurt Giberson large CSO tunnel project in Dearborn, Michigan, proved to be uneconomical because of geotechnical challenges, and was cancelled in 1995. However, a solution to the untreated overflows was still needed, so a multi-year process was initiated to re-evaluate every design solution and potentially develop new alternatives. Various tunnel systems were reviewed, as well as sewer separation, which had always been the highest cost alternative. Retention treatment basins, which had been rejected, due to land constraints, were looked at again. Also, a downspout disconnect program was launched to reduce roof top run-off contributions to the sewer system. A joint feasibility study with an adjacent community was also conducted to see if a shared tunnel would reduce costs through its economy of scale (680 million litre volume). The joint tunnel was a tough option, as it would require complex controls to minimize surging and was a high construction risk due to poor rock conditions. Also, since it only provided capture capacity, there was a possibility that costly screening and disinfection facilities would be required in the future. These challenges, plus minimal cost savings, led to a decision to pursue other options. It was during this lengthy analysis that a very different alternative gained attention. The new concept, referred to as a “treatment shaft,” provides integrated combined sewer overflow (CSO) multitreatment in a single vertical shaft. This design concept solved many of the hydraulic and regulatory issues facing the project, and was eventually adopted as the primary CSO control alternative. Treatment shaft features In addition to the complete capture of CSOs for the vast majority of storms, the patented “Treatment Shaft Technology” also provides high-rate flow-through treatment of overflows beyond its storage capacity, including skimming, settling, screening and disinfection of flow rates in excess of 52,868l/s. (Figure 1).

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14 | September 2011

The treatment shafts are constructed using the sinking caisson construction method.

A key feature of the treatment shaft design is its low hydraulic head loss and low upward velocity that promotes settling of suspended organic and inorganic solids. During the peak hourly average flow rate of the 10 year, one hour design storm, upward velocity within the shaft is less than 30 millimetres per second. This drops dramatically after the peak hourly average so that one hour later it is only 3 millimetres per second. Head loss through the entire treatment shaft is only 0.18 metres (with fine screening) during the peak five minute average of the 10 year, 24 hour design storm. This also drops dramatically afterward.

Treatment shafts can also work with a variety of disinfection methods. If disinfection is not required, the design still provides capture volume, skimming, settling and screening, all within a compact footprint that is only about 15% of surface storage (Figure 2). Horizontal raked bar screens (5 millimetre spacing) are used on the effluent side. The horizontal configuration ensures that all flows, high or low, are screened with minimum velocities through the screens. The entire flow is in contact with the screens, achieving a highly efficient perpendicular flow path. During a treated overflow event, the screens are continually raked by a hydraulically driven system.

Environmental Science & Engineering Magazine


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Stormwater Management All materials collected during operation automatically end up at the bottom of the shaft. They are pumped back to the treatment plant after the storm event, without additional handling or the use of trash containers. All maintenance of the horizontal raked bar screens can be performed top side. A robust, automated flushing system at the conical bottom of the shaft, using jets designed with computerized fluid dynamics, provides cleaning of the facility in preparation for the next storm event. The jets create a swirl effect that re-suspends settled materials and scours the cone-shaped bottom, followed by dewatering with small pumps to deliver the captured flows to the treatment plant within 24 to 48 hours. The jets can use the combined sewer water within the shaft, or a potable water source, if additional flushing is required. Comparison to traditional alternatives Common flushing systems for basins, such as tipping buckets, are unable to fully scour the bottom surface. This can result in odour problems and require time-consuming manual cleaning. In tunnels, the typically flat slope promotes settling of materials that are not removed by later storm events. Over time, significant loss of capture volume can occur, again requiring manual cleaning. The automated flushing process and conical bottom of treatment shafts eliminate these problems. Another advantage over tunnels is in surge control. Tunnel design often requires complex modeling to determine potential surging during filling. As tunnels fill rapidly during large storm events, tremendous hydraulic forces occur that can cause dramatic surges and grade line elevations, as well as structural damage. Computer modeling required to predict such phenomena is complex and can be expensive. Surge control structures and monitoring systems are then needed to avoid these undesirable effects, adding substantial cost to a tunnel system. Treatment shafts resolve these issues, because their large diameter and configuration act as a surge control structure. Lower head losses in treatment shafts also help eliminate the need for booster pump stations, often required for tunnels and basins. www.esemag.com

Figure 1. Patented Treatment Shaft Technology.

Figure 2. If disinfection is not required, the design still provides capture volume, skimming, settling and screening, all within a compact footprint.

The compact footprint of treatment shafts means that far less surface area is required for siting, compared to retention basins. In terms of their land requirements, they are only 15% of the size of basins of the same volume. The upward flow of the effluent discharge allows for the use of the horizontal raked bar screens, which require no surface building. This means that the entire system (shaft, screens, disinfection and control systems) can be placed under the shaft

cover, with virtually no surface presence noticeable to the public. With a concrete cover, the top can be used for a variety of secondary purposes, from parking to recreation. Physical model study Prior to final design, a one-nineteenth scale physical model (Figure 3) was constructed at the University of Michigan Ann Arbor, to test the expected performcontinued overleaf... September 2011 | 15


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Stormwater Management

Figure 3. One-nineteenth scale physical model.

ance of treatment shafts. The study confirmed that the shaft itself introduces only 0.126 metres of head loss, during the peak flow rate of 52,868 litres/sec. This ensures successful gravity operation during flowthrough operation. Also, the very low velocities through the structure provide negligible flow inertia. This eliminates the potential for undesirable surges. The hydraulically efficient horizontal raked bar screens add only 0.051 metres of additional head loss. Minor modifications to the upstream sewer system can be included in projects, so that no net additional head loss occurs. This eliminates the need for booster pump stations. Construction projects Four major projects based on this new

Figure 4. Sinking caisson construction method.

design are currently being constructed to control CSOs in Dearborn, Michigan. The first of these projects became operational in December of 2010, and the second came on line in 2011. Construction costs for these projects were 30-50% lower than comparably sized alternatives. Treatment shafts are expected to reduce capital costs by over $100 million (USD). Ongoing operations and maintenance will be less complex than basins or tunnels. The treatment shafts are constructed through soft clay and into limestone rock, using the sinking caisson construction method (Figure 4), to depths up to 52 metres. One of the largest of the shafts controls peak flows of 53 cubic metres per second. This project has a diameter of 29

metres and a capture volume of 25.7 million litres to provide 10 minutes of disinfection contact time for the peak hourly design flow rate. Conclusion Treatment shafts are now proving that they can provide significant benefits. As such, this CSO alternative is now being considered by many cities across Canada and the US. Kurt Giberson is with Public Works Consulting LLC. He was Director of Public Works for the City of Dearborn until retiring in 2008, and was responsible for its CSO projects. E-mail: kag@publicwrx.com

> Water & Wastewater Systems > Stormwater Treatment & Management > Modeling > Hydrologic & Hydraulic Analysis > Environmental Planning > Distribution, Collection, Treatment

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Environmental Management

Ontario developing Best Management Practices for hydroelectric facilities

A well done EA will identify potential impacts and concerns likely to be expected on a particular hydroelectric project.

s private landowners, as well as stewards of public lands and waters, the waterpower industry has an important role to play in the sustainability of the ecosystems in which its developments and redevelopments take place. A key component of this role has been the development of Best Management Practices (BMPs) in support of the Class Environmental Assessment (Class EA) for Waterpower Projects in Ontario. Led by the Ontario Waterpower Association (OWA), BMPs provide the industry with the best available information and the tools needed to protect, restore, and, where necessary, mitigate undesired effects on the natural environment. Building on the OWA’s past successes with BMP Guides for American Eel and Waterpower in Ontario (2010) and Lake Sturgeon and Waterpower in Ontario (2009), the OWA recently completed the BMP for Channel Darter and Waterpower Operation and Development and the Practitioner’s Guide to Federal Requirements for Waterpower Development Envi-

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ronmental Assessment Process in Ontario. It has recently commenced the BMP for the Construction of Hydro Facilities. BMP for Channel Darter The OWA, with support from Environment Canada and Fisheries and Oceans Canada, commenced development of the Best Management Practices Guide for Channel Darter and Waterpower Operation and Development in Ontario in November 2010. This guide follows a similar framework to the previous BMP guides by utilizing Fisheries and Oceans Canada’s “Pathways of Effects” approach to identify potential effects and reduce/eliminate environmental impacts through BMPs. This guide will provide practical approaches to mitigate potential impacts to the Channel Darter, and allow waterpower projects to proceed, while recognizing the significance and sensitivity of this species at risk. Natural Resource Solutions Inc. was retained to develop this BMP. The following were represented on the steering committee and/or participated as expert

reviewers: Department of Fisheries and Oceans Canada (DFO), Ontario Ministry of Natural Resources (MNR), Trent University, OWA, and Parks Canada. Federal Requirements For Waterpower Development Revisions to the Practitioner’s Guide to Federal Requirements for Waterpower Development Environmental Assessment Processes in Ontario were completed in June 2011. Fisheries and Oceans Canada and the OWA had finalized this document in March of 2006. Recognizing that a great deal had changed over four years, with new and updated legislation, the OWA and DFO began to revise and seek comment from federal and provincial agencies, in June 2010. Having received comments from the Canadian Environmental Assessment Agency, MNR, DFO and the OWA, the guide is now complete. BMPs for the Construction of Hydroelectric Facilities The newest addition to OWA’s BMPs is the development of a Best Management Practices Guide for the Construction of Hydroelectric Facilities. This will be a

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Environmental Management substantial update to Ontario Power Generation’s (OPG) guide, that was produced in 2003 and was no longer being maintained. As a key reference component of the Waterpower Class Environmental Assessment, it was decided to update this document with the best available knowledge. OWA, with support from both MNR and DFO, awarded the contract to GENIVAR Inc. and Natural Resource Solutions Inc. to develop the guide. The project commenced in April 2011 and has a targeted completion date of October 2011. This project is guided by a steering committee consisting of representation from OPG, MNR, OWA and DFO. The guide will enable proponents to address the potential environmental effects associated with an activity, identify measures for prevention or mitigation of the effect, and identify ways to measure effectiveness of measures taken to reduce the impacts. The BMPs will also provide approaches for monitoring activities to provide early warning of a potential situ-

The guide will enable proponents to address the potential environmental effects associated with an activity, identify measures for prevention or mitigation of the effect, and identify ways to measure effectiveness of measures taken to reduce the impacts. ation and of the success of measures taken to mitigate it. Successful application of BMPs is founded on the Class EA for the project. A well done EA will identify potential impacts and concerns likely to be expected on a particular hydropower project during the execution of the five EA phases: concept, definition, assessment, documentation, and implementation. Information will also be considered that comes from coordination/integration with other legislative and regulatory requirements. www.esemag.com

As part of the EA process, it is essential to ensure that there is sufficient Aboriginal community engagement and public involvement to complete the identification of environmental impacts that will require the application of BMPs. Environmental governance Development of BMPs provides guidance for the waterpower industry and continues to foster heightened environmental awareness that all owners and developers share in developing and operating water-

power facilities in Ontario. BMPs are also a strong step forward in facilitating the governance of watersheds, where waterpower facilities operate. BMPs, by definition, accept that knowledge about the environment is imperfect and present the best available information to be considered for the development and operation of facilities. For more information, or for copies of the guides, visit www.owa.ca

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Pumps

Improving the energy efficiency of pumping systems By Michael Blundell umps are everywhere in modern industry! Whether in water supply systems, wastewater treatment facilities, factories, refineries or power plants, we rely on this essential equipment to drive processes, or simply to move water to where we need it. Of course, all this activity requires lots of energy. According to a study prepared by a major European industrial research institute, approximately 20% of the energy used by industry is consumed by pumps and related equipment. KSB, one of the world’s largest manufacturers of centrifugal pumps, is tackling the energy efficiency issue head-on with a multi-faceted strategy that addresses all aspects of energy use in pumping systems. Launched in April, the “Fluid Future®” initiative is aimed at helping pump users optimize the performance and minimize the full life cycle cost of pumps and the systems they help drive. Taking a systems view The starting point is a comprehensive overview of the operating conditions under which each pump will operate. Gathering the necessary data for a newly designed system is usually straightforward, but can be more challenging with an existing installation. For this reason, KSB has developed special testing tools, that help determine the pump operating parameters in situ. Selecting the right equipment Once the full operating envelope for each pump has been determined, it is time to select the best piece of equipment for the job. This isn’t always a simple task, given the enormous variety of pumps available on the market. And, once an appropriate type of pump has been selected, it is equally important to specify the optimal configuration. This might involve the selection of impeller types, seals, special corrosion or wear-resistant materials, and so on. KSB’s EasySelect® selection and configuration software can be a valuable tool for narrowing the search. Naturally the help of a skilled application engineer is also important for confirming and refining the choice.

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20 | September 2011

Trimming a pump impeller to fine-tune the energy efficient ‘sweet-spot’.

Sweating the details: a key to improved energy efficiency It is well known that each pump has a ‘best efficiency point’ (BEP) or sweetspot – a combination of head (output pressure) and flow rate. This is where it will deliver its best performance in terms of both energy efficiency and service life. A key to getting the best overall system performance is to make sure that each pump in the system is operating as close as possible to its BEP. This isn’t always easy. Pumps, like shoes, tend to come in standard sizes, which can make it difficult to get a perfect fit. Flow and pressure requirements can vary significantly, especially in water and wastewater systems that need to respond to changes in demand as well as events such as stormwater surges. There are several possible strategies for dealing with these challenges. The ‘fit’ issue can be addressed by impeller trimming, a process of reducing the diameter of a standard impeller to slightly reduce the output of the pump. Done properly, this shifts the BEP so that optimum performance of the pump will precisely match the requirements of the application. Where flow requirements change sig-

nificantly, one of the best approaches is to have the load shared by a number of relatively small pumps, that can be operated independently. Here, the number of pumps running at any time will be set to match the overall flow requirements, with each individual pump operating near its BEP. Fine-tuning can be done by having one or two pumps equipped with variable frequency drives (VFDs). VFDs are control devices that enable an operator to adjust the speed at which a pump runs. This enables the operator to adjust the output of the pump, while still having it run at nearoptimal efficiency. A further step in maximizing energy efficiency involves the use of ultra-highefficiency motors. These tend to be more expensive than conventional electric motors, but over the lifetime of the pump set, which can easily exceed 20 years, the extra cost is usually recouped. Case Studies When a pulp producer in western Canada downsized their mill in response to changed market conditions, they found that their boiler feed pumps were oversized for the new operating requirements. Instead of replacing the pumps, it was recommended that the existing 50-year

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Pumps

Data indicate that energy costs are the largest factor in the total cost of pumps in industrial settings.

old pumps’ internal hydraulic components be replaced with new impellers and diffusers so that the pumps’ optimal operating point matched the new requirements. This resulted in a 23% improvement in energy efficiency compared to running the pumps in their original configuration and reducing flows by valves or orifice plates.

Sometimes more pumps are the best answer‌ A large municipality required a flexible pumping solution for a wastewater treatment plant. In order to handle highlyvariable flow rates, a multi-pump configuration was proposed. The majority of pumps were to operate at fixed speed, close to their BEP, while two pumps would be equipped with VFDs. The operator could meet a wide range of flow conditions by varying the number of fixed-speed pumps running at any time, then fine-tuning the output of the two variable speed pumps. Making sure that each pump would operate close to its best efficiency point reduced the projected energy costs by a significant amount. Careful design of the complete configuration also reduced the capital cost of the facilities in which the pumps would be housed, thanks to optimization of the size of valves and pipe work. ‌And sometime fewer can do the job better! A company in northern Alberta was launching a pilot project using an innovative process to extract from oil sands

deposits. The project aimed to produce 10,000 barrels of oil per day with no net water use. The company initially requested two high-pressure boiler feed-water pumps (BFWP), plus two booster pumps that would be configured to feed BFWPs. By selecting a type of pump that didn’t require a booster, the company saved about 15% of the overall capital cost of the pumping system. Reducing power consumption and maintenance will ensure further savings over the long run. In summary‌ Fluid Future is a comprehensive program that looks at all aspects of pumping systems to ensure that energy is used as efficiently as possible. This relentless focus on operating efficiency reduces operating costs, while also supporting efforts to reduce the environmental impact of industrial facilities. A clear win-win all around! Michael Blundell is President of KSB Pumps Inc., Ontario. E-mail: mblundell@ksbcanada.com

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Water Treatment

How to design your own water treatment system By John D. Reid fter 40 years living in our King City house north of Toronto, my wife Jane and I retired in June, 2009, to the shore of the St. Lawrence River, one km west of Brockville’s city limits, in the beautiful Thousand Islands. Here, water conditioning is not required as the St. Lawrence River water is very soft and free of excessive iron. Our Brockville house draws its water from the St. Lawrence River, and household drinking water was being provided from a bottled water dispenser. Many years ago I had "winterized" the river water intake piping and the pump house. So, while our move from a deep water well to a river water source assured us of year-round unlimited house water supply volume, we found ourselves needing to periodically haul home from the grocery store large bottles of drinking water. Carrying these bottles and lifting them onto the drinking water dispenser unit was

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something of a challenge to my now 81 year old muscles. So I decided that I should devise a water treatment system that would provide drinking water for the house from a kitchen drinking water tap and from the refrigerator water tap (and ice maker), using river water. Further thought resulted in a decision to size the system to handle the entire household. Then, I added a couple of additional criteria to my design thinking. First, the system must be very small, because the proposed location of the treatment system, where the raw water pipe enters the house from the pump house, offered very little space for treatment equipment. My next design thought was that the treatment system must be easily maintained by my "non-technical political science graduate" wife. The final design has complied with all of my requirements and has operated superbly since start-up about 11 months ago. All components were purchased at Brockville's Home Hardware store, except the primary filter which is the key to the success of the system. It permits a quick filter element change and the dirty filter element can be quickly flushed clean in the kitchen sink and reused for the next filter change. This primary filter unit is made by Amiad Filtration Systems Ltd. in Israel. Environmental Science & Engineering Magazine


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Water Treatment My original design had called for a primary filter with a 50 micron disc filter element, but my Amiad unit arrived with a 25 micron disc element, and so that is what is presently providing the primary filtration. As an afterthought I elected to run the water line leading from the system to the refrigerator as well as to the kitchen tap through a Rainfresh “Drinking Water System 2” unit, which incorporates an activated carbon filter element. So we are assured of drinking water of a very high quality. Water from any tap in the house is, however, drinking water quality. Following completion of the system, I had the treated water tested and the design has met its objective. The primary Amiad filter lasts about one week, before pressure loss through the system dictates a change of the primary filter element. Also of considerable importance is that the design includes three pressure gauges which effectively indicate the head loss across all filter elements in the system. Without the gauges one is simply “flying blind”. To check the system I simply flush a household toilet, or turn on a kitchen tap, and then read the gauges as

water flows through the system. The system has also been carefully valved using plug valves which permit simple and quick opening and closing and offer minimum head loss. There is a plug valve on either side of the Amiad primary filter plus a drain valve for this filter. A drain hose leads down to a small pail on the floor under the filter. This valving permits quick changing of the filter element without spilling any water. The two Rainfresh secondary filters each incorporate a bypass valve, thereby permitting a dry change of filter elements when set in the by-pass mode without shutting down the system. Plug valves on either side of the Rainfresh infra red unit also permit easy and dry bulb changing. Finally, instead of assembling the system’s copper pipe plumbing using soldered fittings and possibly burning down the house in the process, I elected to use “Shark-Bite” fittings and plug valves which incorporate “Fast Push-Fit Connections”. With these fittings one simply cuts copper or plastic pipe to the correct length, and then pushes the elbow, tee or valve onto the pipe. No soldering, gluing or “wrench-tightening” is required. In ad-

dition, the fitting or valve will swivel or turn on the pipe to suit whatever final position is desired, all without leakage. And the fitting or valve can be removed from the pipe and re-used using a very inexpensive tool should a change be desired. No doubt, it will always be necessary to change the Amiad primary filter element more frequently as summer progresses and algae forms. However, the Zebra Mussel infestation of a few years ago seems to have done a wonderful job of clarifying our St. Lawrence River water, so I expect reasonably long filter runs. Primary filter element changes take only a minute or two, so I am not concerned, even if daily changes are needed during the summer. Changing a filter element and quickly flushing out the dirty element in the kitchen sink takes only five minutes and certainly beats carrying in a 50 lb water bottle. John D. Reid is a well-known and respected water and wastewater professional, who co-founded Napier-Reid Ltd.

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Drinking Water Treatment

Evaluating household scale water systems for arsenic removal By Jahangir Chowdhury rsenic contaminated groundwater is the main source of drinking water for millions of people in south-east Asia. It is estimated that about 80% of the rural population are drinking groundwater containing more than 50 µg/L maximum contaminant level (MCL). Although the cause of this contamination has not yet been definitely established, geochemical conditions are considered to be the cause of the mobilization of the soluble arsenic. Government and non-government agencies are trying to mitigate the problem by identifying the contaminated sources (mainly tube wells) and introducing removal technologies. The following review is based on findings from the report of a project called “Rapid Assessment of Household Level Arsenic Removal Technologies”. The project was carried out in 2000–2001, under the umbrella of the Bangladesh Arsenic Mitigation Water Supply Project and the Ontario Centre for Environmental Technology Advancement. Financial backing was provided by the UK Department for International Development. Seven household arsenic removal technologies were evaluated for performance: 1. Alcan Enhanced Activated Alumina (Alcan) Alcan is a filtration process through enhanced activated alumina. No chemical is required. The process relies wholly on the active surface area of enhanced activated alumina to remove arsenic from drinking water. Other compounds can also compete for the active sites on the alumina and for this reason other elements, such as iron and phosphate, may accumulate on the surface. 2. BUET Activated Alumina Filter (BUET) The BUET process is sand filtration followed by activated alumina adsorption. Initially, 1mL of potassium permanganate (KMnO4) solution is added to the water as an oxidant to convert trivalent arsenic into the pentavalent form, which is more easily removed from solution. Dissolved iron present in solution undergoes oxidation and is hydrolysed into colloidal sized

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24 | September 2011

Alcan enhanced activated alumina.

BUET activated alumina filter.

particles. Such particles adsorb arsenate and remove a component of the arsenic. The highly efficient activated alumina removes arsenic that is not removed in the sand filter from solution. 3. DPHE/Danida Two Bucket System (DPHE/Danida) DPHE/Danida is a sedimentation followed by sand filtration process. Aluminum sulphate (Al2(SO4)3), with minor amounts of potassium permanganate (KMnO4) as an oxidant, are added to the tube well water. The aluminum compound undergoes a process called hydrolysis and is converted into a jelly-like compound of aluminum hydroxide. The sulphate stays in solution, as does the potassium permanganate. Arsenic present in the water is adsorbed onto the colloidal sized floccules and, as these aggregate, they start to settle. The larger the floc size, the more rapid the settling rate. 4. GARNET Home-made Filter (GARNET) No chemicals are added during use of this technology, which is essentially a brick and sand filter. The iron rich brick chips must contain some free lime and reduced iron compounds (Fe(II)) within the porous solids, originating from the baking of clay, iron compounds and calcium carbonate at high temperatures under re-

ducing conditions. Together with oxygenation of the water in the filter, this will promote oxidation and hydrolysis of the iron held in solution. Arsenic is simultaneously coprecipitated and removed with the iron, to form an arsenical iron oxyhydroxide. 5. Sono 3-Kolshi Method (Sono) Sono is a filtration process through sand-iron, followed by sand-charcoal media. No chemical additions are made to the water. Main chemical reactions occur within the top kolshi where the majority of arsenic is removed (>95%). Here the presence of a layer of metallic iron induces low pH conditions, causing arsenic to be precipitated from solution onto iron oxyhydroxide. An arsenical iron oxyhydroxide compound will also accumulate in the second kolshi containing the sand-charcoal filter material (minor coarse brick particles), allowing any arsenic not removed in the top kolshi to be recovered. 6. Steven’s Institute Technology (Stevens) Stevens is a sedimentation followed by sand filtration process. 3.8 g of iron sulphate mixture containing a minor quantity of calcium hypochlorite (an oxidant) are added to 20 L of well water. Following rapid stirring of the solid mixture into the water, the iron compound continued overleaf...

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Drinking Water Treatment

Tetrahedron ion exchange resin filter.

DPHE/Danida two bucket system.

dissolves and the iron undergoes rapid hydrolysis and the formation of colloidal flocs occurs. Conversion of As(III) to As(V) takes place through the action of the added oxidant as well as being catalysed by the oxidation of Fe(II) to Fe(III). Dissolved arsenic within the water is

coprecipitated and adsorbed onto the iron floccules, which settle to the bottom of the bucket. 7.Tetrahedron Ion Exchange Resin Filter (Tetrahedron) Contact of the well water with sodium hypochlorite (“Chlorine tablets� NaOCl), an oxidizing agent, results in the oxidation of arsenic from its trivalent to its pentavalent form. It also adds significant chlorine taste to the water but helps min-

imize bacterial growth. The ion exchange resins are highly selective, removing arsenic and other compounds with a similar valence. It is the surface of the resin beads that makes the material function. Arsenic removal relies on the availability of an adequate number of active sites on the material. Regeneration of the resin may be carried out periodically by flushing with salt (NaCl) solution. Ideally this should be done at a centralized facility. Regeneration frequency will depend on the nature of the water being treated. Conclusions Assessment of the seven technologies’ technical performance was based on three main issues related to the quality of feed and treated waters. These were arsenic, non-arsenic water chemistry and bacteriological analyses. Results indicate that three technologies, Alcan, BUET and Sono, consistently reduce arsenic concentrations below 0.05 mg/L in all areas tested. Two technologies, Stevens and Tetrahedron, performed well at many tube wells but in some instances failed to reduce arsenic to below 0.05 mg/L. The two remaining technologies, GARNET

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Drinking Water Treatment and DPHE/Danida, performed less well. DPHE/Danida is generally not effective at reducing arsenic to below 0.05 mg/L, if well water arsenic concentration is above approximately 0.12 mg/L. At feed water concentrations below this, DPHE/Danida is generally effective. GARNET is unpredictable and it is not yet clear why. With regard to non-arsenic chemical parameters, the technologies do not appear to increase any of the significant water parameters tested above accepted drinking water standards. The exception is DPHE/Danida, which on occasion allows both manganese and aluminium levels to rise above accepted drinking water standards and WHO recommended health levels. With the exception of Tetrahedron and Stevens (which have a chlorination step), faecal contamination was found in all technologies tested at levels that represent significant risk, based on WHO guidelines. Sono-3-Kolshi and Alcan technologies are of greatest concern, since heavy contamination was found in many treated water samples. High levels of contamination were also associated with GARNET and DPHE/Danida in several samples.

GARNET homemade filter.

Sono 3-Kolshi method.

There were issues with BUET in a few samples, but the reason for this is unclear. The level of faecal contamination acceptable for untreated drinking water in rural situations is a matter for international debate. While it is unlikely that the WHO standards of zero faecal coliforms per 100 mL are realistic in this context, it is probable that counts of over 100 cells per 100 mL will remain of concern.

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September 2011 | 27


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Water Supply

Kenora installs new 3.4 km watermain under Lake of the Woods By Marco Vogrig and Bob Romanetz

Figure 1. Location plan of the Kenora marine watermain.

he City of Kenora was confronting an increasing number of issues on a key marine watermain. Whenever a break occurred, over 2,500 residents, a seniors residence, and a district hospital suffered a loss of water and unwelcome “boil water” advisories. Repairs required expensive, specialized services provided by diving contractors, followed by meticulous pressure and bacteriological testing to ensure the repaired line was again delivering potable water conforming to stringent quality standards. The City had a difficult choice: keep fixing the failing 400 mm diameter watermain constructed in 1977, or replace it entirely. To address these options, the City retained AECOM’s Winnipeg office. Long marine watermains are not common in Northwestern Ontario. Although AECOM Manitoba had not designed such a facility under the current regulatory guidelines, the firm had conducted a study for the City in 2003. This study identified over 20 separate defects along the existing watermain. After reviewing possible causes (e.g., pressure spikes, thermal changes, or material issues), the study evaluated three options: repair

T

28 | September 2011

clamps, twinning, or replacement. Replacement was considered the most favourable option, and AECOM commenced predesign work in February 2008. Once the design was done, Galcon Marine Ltd. was selected to construct the project. The new marine watermain is 3.4 km long, (see Figure 1), with seven shore connections (shown in green). Provisions were also made for future connections (shown in orange). Site investigations Kenora provided background data about the watermain, including a GIS database, aerial photography, lake bathymetry, and co-ordinate information from a 2006 diver survey. AECOM compiled this information into a single coherent drawing that highlighted several anomalies. The firm then organized a diver and GPS survey to examine geotechnical conditions along the route, water depth readings, closed-circuit television (CCTV) records and water current measurements. The resulting 3-D picture of the lake bed made precise plan/profile drawings possible. Material selection Due to the main’s failure history,

Kenora asked AECOM to evaluate suitable alternative materials. High-density polyethylene (HDPE) was favoured for its high degree of notch resistance and its forgiveness in longitudinal bending, particularly during tow-out and sinking. A review was made of PENT test results, whereby thermoplastics are subjected to accelerated environmental conditions, with each hour of testing representing approximately 13 years of service. Many 1970s cell classifications had low PENT values (under 10 hours), but PE4710 demonstrated a PENT value of 500 hours. The project team recommended PE4710 over conventional PE 3408/3608 materials, due to its increased hydrostatic design strength, slow crack growth (SCG) resistance and improved fusion characteristics. Hydraulic modeling Since the new routing lengthened the watermain considerably, system hydraulics were carefully reviewed. An EPAnet water distribution model of the City was modified to reflect future conditions. The study included three main elements: 1. An assessment of the watermain’s hydraulic properties. 2. Performance criteria for different syscontinued overleaf...

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Water Supply

Working at the Courthouse tie-in.

30 | September 2011

tem demands and boundary conditions. 3. Extended period simulations to find typical pressure fluctuations (cyclic loading), to determine the minimum pipe diameter and economical wall thickness for the replacement pipe. Modeling system performance was complicated by the constantly changing conditions within both the water treatment plant’s high lift pumps on the upstream end, and at the Norman Booster Pumping Station and Keewatin standpipe on the downstream end. The final decision was to retain the pipe diameter of 400 mm, with a relatively thick wall (dimension ratio DR 11). Economic and social impacts The original watermain was suffering substantial leaks, particularly at the old repair clamp locations. Water losses of 30 to 40 percent were not uncommon, as measured at the City’s water plant (compared to the normal 10 to 15 percent for such systems). The new watermain reduced treated water loss, while lowering maintenance costs. The new watermain brings considerable benefits to the City’s 2,500 residents on the west end, and to the Lake of the

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Water Supply

An excavator works within a silt curtain to avoid disturbance to fish habitat.

Woods Hospital. It should substantially reduce breaks, service interruptions, and the resulting need for precautionary boil water advisories. Although seven shore tie-ins were made, only two such advisories were required during installation. The project team worked with the Northwestern Health Unit to manage the issuance and withdrawal of each advisory. Environmental impacts Environmental concerns were paramount, particularly around the sensitive fish habitat within Lake of the Woods. A number of federal agencies and local stakeholders were consulted during the project, and all outstanding issues were logged and tracked. The Ministry of Environment agreed that a Certificate of Approval was not required. However, AECOM did prepare a Municipal Class Environmental Assessment (EA). The project was advertised in the local press, and the EA and design drawings were made available for public review. The marine works conformed to the conditions of a shore works permit granted by the Ministry of Natural Re-

sources, and with guidance from the Department of Fisheries and Oceans. The permit set deadlines for completion of inwater work, and required silt curtains around marine excavation areas. Installation Marine watermain installations can pose considerable risk, and the consequences of failure are severe. The new installation was substantially more complex than the original line due to additional shore connections, environmental concerns, continuation-of-supply issues, and additional utilities installed since the 1970s. In July 2009 Galcon mobilized equipment to the site, including a barge, tug and work boats. Firstly, a number of pipe lengths were fused together, fitted with weights, air tested and stored at the Kenora Forest Products yard. To monitor the fusion process, AECOM reviewed the temperature and pressure information on each butt-fusion weld. Then air-filled pipes were joined together, towed into place, and gradually lowered to the bed by adding treated water. No air pockets formed during the sinking activities, continued overleaf...

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Water Supply which can be a common problem with such installations. The watermain was then pressure tested and chlorinated. Service issues Construction was made more challenging by the need to maintain service to residents during installation. The project team developed a continuity plan to minimize the number of boil water advisories required, and to ensure connections went smoothly. The plan included a valve numbering system that fostered a stepby-step procedure for each tie-in (some required up to 17 separate steps). A time limit for water shutoffs was imposed by the storage capacity of the Keewatin standpipe. Once work commenced, the tank would normally have been disconnected from the system. Instead, temporary overland hoses were used to keep a nominal supply of water flowing to the standpipe, extending the water shutoff times. Following chlorination, and after the required contact time had elapsed, chlorinated water was discharged to the nearest manhole or lift station within Kenora’s wastewater sewer system. Upon comple-

Air testing the assembled pipe lengths.

tion of pressure testing, two bacteriological samples were shipped to an accredited laboratory in Thunder Bay. After sample testing and approval, the line was put into service. Impediments to construction AECOM incorporated detailed infor-

mation within the bid documents, including the record drawings for the existing watermain, to make bidders fully aware of the site conditions. However, there were a great number of existing services (buried, overhead or on the lake bed), including watermains, sewage forcemains,


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Water Supply hydro, telephone and gas lines. Log booms also obstructed the movement of boats across the mouth of the Winnipeg River, and bedrock levels were highly variable over short distances. These complicated crossings of the new watermain, and the placement of stabilizing legs on the contractor’s barge. All existing marine services were marked with coloured buoys; however, a number of unmarked and abandoned services and structures came to light during construction, such as an old sheet pile wall, roof drains and old manhole bases. Currents Strong currents occur in parts of the lake. Velocities of up to 1 m/s have been observed across the mouth of the Winnipeg River. The original design dealt with this issue by additional weighting of the pipe. The project team developed an alternative that connected existing weights from the abandoned watermain to those on the new watermain. This faster and simpler installation method resulted in considerable cost savings. Safety The near-shore excavation required

divers to work directly adjacent to excavators in zero-visibility water. AECOM’s bid documents required the contractor to provide detailed method statements for review before such hazardous activities commenced. This work was undertaken during the busy summer season on Lake of the Woods, amid the constant activity of float planes, fishing competitions, wake boarders and cottagers. To manage these risks, Kenora and AECOM staff maintained communication with businesses, the Ontario Provincial Police and area residents. The City of Kenora also conducted radio interviews to keep the public informed. Surveys and records Upon completion of the installation, Galcon conducted two surveys to verify the alignment and installation: side scan sonar and a diver survey. AECOM used the sonar images to produce the as-built drawings. The divers also produced DVD records of each pipe segment. Future benefits The project included future connections for servicing of a popular cottage development, and preserved the potential

for future twinning of the marine watermain. Additional tie-in points installed as part of the project will create redundancy looping in the water distribution system as those projects come on line. Maintenance is now considerably easier. The addition of electrofusion saddles and air release points will obviate the need for the City’s operations staff to enter old valve chambers, which are considered a confined space. The original watermain was abandoned and left in place to minimize environmental impacts. Funding The final cost of the project was approximately $2.6 million. The governments of Canada and Ontario provided two-thirds funding, with the City of Kenora providing the balance. Government funding was provided through the Building Canada Fund. Site work took place between July and November 2009. Marco Vogrig, P.Eng., was the project manager for the City of Kenora. Bob Romanetz, P.Eng., directed AECOM’s project team.


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Stormwater Management

How Canada’s largest airport co-exists with one of Toronto’s last green spaces By Randy McGill mid the rapidly developing landscape of the Greater Toronto Area sits a unique ecosystem in the city’s west end. It is one of the few remaining areas that offer a corridor for animals to move north and south through the city, and features a natural, eight-kilometre creek bed that contributes significantly to the local watershed system. Next to it is Toronto’s Pearson International Airport, with its 4.2 million square metres of concrete, on which over 425,000 planes a year are maintained, refueled and, depending on the season, deiced. Yet Toronto Pearson provides a successful case study for how a transportation hub, city gateway and economic centre can co-exist successfully within a sensitive ecosystem. In fact, over the last 15 years, the airport has developed, built and improved one of the most advanced

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The creation of a centralized deicing facility has been instrumental in controlling deicing fluid runoff, and ensuring its proper capture, containment and treatment during wintertime operations.

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Stormwater Management stormwater programs of any airport in North America. It can actively manage 299,260 m3 of storage, which is equivalent to the amount of water in 25,000 backyard swimming pools. Recognizing the need to improve Airport and aircraft operations, including fueling and deicing, require the use of chemicals that have the potential to damage the local ecosystem. Stormwater runoff from the large paved areas has the potential to flood and erode nearby creek banks. In the mid 1990s, the use of aircraft deicing fluids substantially increased to the point that it became clear that changes were necessary. In 1989, Transport Canada announced the need to expand Toronto Pearson to meet the requirement for aviation services in the Southwestern Ontario area. As a result of environmental assessments, it was apparent that stormwater impacts from the expansion and airport operations had to be managed and mitigated. Aided by the airline community, Transport Canada’s environmental planners designed a stormwater program that would tightly control runoff and maintain proper checks and balances to protect the surrounding ecosystems. A combined approach of source control, along with end-of-pipe facilities, has proven to be successful. Indeed, the stormwater program covers the airport’s

entire 1,800 ha. It is based on a 100-year return period (where necessary) to protect downstream infrastructure, and has the ability to capture and treat the first 25 mm of stormwater downstream of any source of contamination. In addition, the program provides a high level of environmental protection from the approximately two billion litres of jet fuel loaded onto aircraft annually. The Central Deicing Facility is also a key component of the stormwater program at Toronto Pearson, allowing for the capture

and containment of deicing runoff. World-class facilities Catch basins and a complex stormwater sewer system, under the tarmac, capture and direct runoff. Once in the drainage system, gravity takes over and guides stormwater to one of Toronto Pearson’s four major stormwater facilities. Three of these are underground, and one is a bio-engineered pond. At the underground facilities, sedimentation is accomplished over a 24-48 continued overleaf...

Stormwater processed through Toronto Pearson’s Moore’s Creek stormwater facility is rehabilitated and released into Moore’s Creek, an eight-kilometre creek bed running through airport property that contributes significantly to the local watershed system.

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Pearson’s Stormwater Facilities Moore Creek Stormwater Facility The Moore Creek stormwater facility is a $30 million facility built under the airport’s Infield Terminal. Out of the four Toronto Pearson stormwater facilities, it is the largest, and consists of a 42,000 m3 underground tank and two ponds providing dry surface detention storage, which store 26,000 m3 and 16,000 m3, for a total storage capacity of 84,000 m3. It maintains a drainage area of 384.6 ha. Aeroquay Crescent Stormwater Facility Located under the outbound roads at Terminal 1, the $6.8 million Aeroquay underground tank can capture 7,000 m3 of runoff and has an oil-water separator. It maintains a drainage area of 31.74 ha. Carlingview Stormwater Facility The Carlingview facility was one of the first of the modern stormwater facilities at Toronto Pearson, with construction commencing before the airport ownership

transferred from Transport Canada to Greater Toronto Airports Authority in 1996. After a $3.9 million expansion in 1999, the facility now has a capacity of 17,000 m3 of runoff in its two underground tanks and an oil-water separator. It maintains a drainage area of 58.53 ha. Etobicoke Creek Stormwater Facility The $10.9 million bio-engineered treatment wetland for polishing water quality has the capacity to contain 54,000 m3 of runoff. The facility contains three sections: a forebay for sedimentation and two cells for treatment utilizing vegetation. It maintains a drainage area of 318.41 ha. Surface Ponds There are 11 additional stormwater surface ponds throughout the airport property, which together have capacity for 115,360 m3 of runoff. These ponds are scattered throughout the airport property, with some located between runways and nearby major highways at the edge of the airport. The surface ponds maintain a combined drainage area of 381.27 ha.

Stormwater Management hour hold time before an oil-water separator eliminates any traces of hydrocarbons. Upon testing, if other chemicals are present, the airport sends the stormwater to municipal sanitary facilities for further treatment. In the winter of 2007-08, the airport discharged 337,098m3 of runoff to sanitary facilities for further treatment. If the runoff is deemed clear from contaminants, it is drained to the creek. Each year, the spring melt and rain kick the system into full gear, resulting in the stormwater facilities’ most active period. Overflows exist at each facility to ensure stormwater is directed safely to receiving waters. Pearson’s stormwater system facilities are unmanned and fully monitored remotely. Each day, one of the airport’s environmental team of nine will check the facilities to ensure smooth operations. In addition to regular monitoring, Toronto Pearson proactively tracks weather forecasts, and schedules additional facility monitoring as needed. The stormwater program also includes a rigorous sampling program, and, throughout the year, general chemistry

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Stormwater Management sampling occurs on a weekly basis. To ensure environmental compliance during the winter season, a daily sampling occurs around the airport, both as grab and composite. In the summer, each of the facilities undergoes a full clean-out and maintenance program. To support the water treatment system, Toronto Pearson has developed and runs an extensive spills response and cleanup program. Although the cleanup of fuel spills is the responsibility of the fuelling party, the airport oversees this with a team made up of personnel from several airport departments. They respond according to Toronto Pearson’s Emergency Response Procedures (ERP). An Environmental Emergency Contingency Plan takes the ERP a step further and addresses any potential environmental contamination. Source control procedures and detailed training of airport staff and tenants that could impact stormwater are also a key component of the success of the stormwater program. Toronto Pearson requires all tenants to develop emergency procedures in the event that a spill does occur. Looking forward As weather patterns change and the demand for aviation increases, the airport will need to keep pace. The airport property is confined on all sides by existing development; there is no way to expand out to build future capacity. This limited ground space makes it less desirable to use existing land for expanded stormwater facilities. Yet, at approximately 15 to 25 times more expensive than traditional surface ponds, building underground is a costly undertaking. This does, however, significantly reduce wildlife concerns associated with large ponds. Toronto Pearson has airside capacity for one more runway. Should it be built, it will require the construction of an additional stormwater facility with a capacity of around 22,000 m3 of water. This is estimated based on the same standards of 25 mm of precipitation for the existing facilities. In the meantime, the airport continues to follow the requirements of the Canadian Environmental Protection Act (CEPA) for managing impacts on biodiversity. It has been working extensively for the past decade with the Toronto and Region Conservation Authority. The air-

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port also has a $3.5 million master plan for the rehabilitation of the local creek, encouraging improved riparian habitat and fisheries. The airport continues to monitor the waterways to determine the effectiveness of previous restoration works and to identify any future concerns. In addition, the Greater Toronto Airports Authority’s Environment Management System, certified to ISO 14001 since 1999, mitigates the environmental impact of other airport operations, such

as resource use and waste management. Toronto Pearson continues to consider how climate change will impact the current stormwater facilities and influence the future needs of the system. Current studies are informing the evolving needs of stormwater at the airport, and indicating what protocols will need to be applied, now and in the future. Randy McGill is General Manager, Environmental Stewardship at Toronto Pearson Airport.

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Water Management

Global mining sector faces severe water management challenges By Victoria Kenrick ccording to some predictions, the world’s population will exceed 8.1 billion by 2030. Demand for water has trebled since 1950 and will double again by 2050. With water being the most important resource in all mining and quarrying developments and operations, its management is emerging as the pre-eminent sustainability issue for this sector. Water can be used and abused. Hard rock mines, in particular, use water in all steps of the mining process, from cooling equipment, separating waste from valuable minerals, to controlling dust. Working with such large volumes of water presents a variety of risks. In recent years there has been renewed public debate globally, where water is scarce, about the mining industry and its sustainability. Tackling water pollution Water pollution problems that can be

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caused by mining include acid mine drainage, metal contamination, and increased sediment levels in streams. Changes in laws, technologies and attitudes have begun to deal with some of the most immediate threats posed by mineral development. But, there are still many

It has been argued that most water pollution caused by mining arises from negligence, not necessity. areas of mining practices and regulations that need to be addressed. Preventable incidents that have occurred recently include massive sediment loading into fish-bearing streams,

the building of roads with acid-generating waste rock, non-compliance with waste handling plans, and repeated violations of water quality standards. To avoid such incidents, mining corporations need to ensure the best pollution prevention strategies are employed in cases where risks can be managed. Another question that should be raised is whether mining should not be allowed to proceed in some places because the identified risks to other resources, such as water, are too great. In the right place, and with conscientious companies, new technologies and good planning, many of the potential impacts are avoidable. Indeed, it has been argued that most water pollution caused by mining arises from negligence, not necessity. Driving sustainable water management With growing competition for water usage within mining, steps towards greater sustainability should involve promotion of the use of poor-grade water, usually underground or sea water, which is not wanted for agricultural or municipal use. Many mining processes can tolerate high-saline water. In addition, by encouraging water recycling as much as possible, companies can move towards a zero water discharge mine. Knowing the volume and composition of the process, and the amount of fresh water running in every unit operation in the plant, enables mine operators to minimize the use of fresh water. The scientific approach involves computer modelling and optimization of flows plant-wide. Among newly-emerging computer modelling approaches to optimize water use and recycling, the most advanced is water pinch modelling. It includes a detailed study of water processes and pollution prevention, which helps with wastewater reuse planning. Preventing water pollution in mining One organization that is leading the way in tackling water pollution within mining is The Environment Agency in Wales, which is working at Cwm Rheidol mine near Aberystwyth as part of a unique

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Water Management

A huge open pit gold mine in Western Australia.

pilot scheme. The mine has historically discharged large amounts of zinc and other metals into the River Rheidol, which means it is failing to meet the good water quality standards required by the European Union's Water Framework Directive. Under a new scheme, toxic metals will be stripped out of the mine water before it enters the river, using an environmentally friendly method whose only energy source is gravity. The treatment system will use a mixture of waste products, including cockle shells and compost, to encourage natural biological and chemical processes that clean mine water. Mining corporations in Australia are taking a more preventative approach and

are currently adopting best practices aimed at preventing environmental damage, rather than repairing damage already done. These programs include borehole extraction to help contain the pollution plume, containment of seepage and pretreatment of all water that is to be released into streams. Environmental solutions company Procon Environmental Technologies has been awarded a $1-million contract by mining giant Vale to install a hydro cyclone oily water separation system at the Moatize coal mine in Mozambique. In the United States, a major public hearing in West Virginia took place in June 2011. After a review of more than

50,000 public comments, the US Environmental Protection Agency announced that it will use its authority under the Clean Water Act to halt the proposed disposal of mining waste into local streams. Water resource management is an integral part of mining, and regulators, industry and the community are increasingly recognizing the importance of managing water resources in a responsible way. The main areas being focused on are finding adequate sources of water, minimizing consumption, reuse, managing waste and remediating contamination. Victoria Kenrick is with Allen &York. E-mail: vkenrick@allen-york.com

Se e Bo WEF us a oth TEC t 42 29

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Wastewater Treatment

New MBR system eliminates sewer surcharges for snack food processing plant

The new MBR system fit nicely into the existing treatment system configuration.

olden Flake Snack Foods was faced with a tough decision, either come up with a solution to stem the $100,000 per month wastewater surcharges it was being assessed, or move its 300,000 square-foot snack food processing plant. The company preferred to find a solution to eliminate the surcharges. If it could reach prescribed TSS (total suspended solids), BOD (biochemical oxygen demand), NH3-N (ammonia-nitrogen) and DO (dissolved oxygen) concentrations, it could receive a direct discharge permit. Then it could convey treated effluent directly into a creek that runs beside its property, and bypass the sewer system altogether. Golden Flake’s wastewater The Golden Flake plant manufactures and distributes a full line of snack food

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items, including potato chips, tortilla chips, puffed corn, corn chips, cheese puffs, cheese curls, onion rings and pork skins. Typically, the facility processes more than 20 million pounds of snack foods per year. The plant’s production mix can vary, causing its wastewater to have varying strength and consistencies, with flow rates ranging from 100,000 to 350,000 gpd. Most of the plant’s wastewater, handled through its on-site treatment facility, comes from the processing of potatoes and corn. No sanitary sewage enters this system. From their arrival on-site, potatoes are carried in a water flume to be peeled and sliced. The slices are then washed and put through deep fryers, before being packaged. Flume and wash water are drained daily and discharged for on-site waste-

water treatment. Raw corn, for the production of corn and tortilla chips, is cooked in kettles with water and lime to loosen and remove the husks. It is then soaked in vats to increase moisture content of the kernels. They are then washed to remove impurities, milled, sheeted to run through ovens, deep fried and packaged. Water from these processes is also discharged after use for on-site wastewater treatment. Raw snack food wastewater is pumped through vibrating screens, which collect 15,000 to 20,000 pounds per week of large food particles. This organic matter is collected and used as animal feed. From the time the facility was originally built, pre-screened wastewater leaving the plant was received at a primary clarifier, with supernatant discharged to the sewer system. Golden Flake is per-

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Wastewater Treatment

The system consists of a pre-aeration tank, and two membrane basins.

mitted to release up to 400,000 gallons of wastewater per day. Stagnant wastewater in the primary clarifier was not aerated or covered and would produce off-odors. The clarifier was located along the edge of a street, where subsequently a housing development had been built, and odour was becoming an issue with residents. “The wastewater being decanted to the sewer system had BOD and TSS concentration levels in the thousands, exceeding maximum surcharge levels,” says David Jones, Executive Vice President of Operations for Golden Flake. “As our surcharges continued to escalate, we began looking for an on-site treatment technology that could not only handle our high-volume peak flows of up to 350,000 gpd, but also produce an effluent that was below the maximum allowable discharge concentration limits for BOD, TSS, NH3-N and DO.” Engineering a solution Golden Flake brought in ADI Systems Inc., (ADI) of Fredericton, New Brunswick, to engineer a solution. The problem was somewhat complicated by the fact the production plant is landlocked. There was no room for site expansion, and little available room for a conventional activated-sludge facility. ADI recommended a membrane bioreactor (MBR) system to treat raw wastewater following the vibrating screens. The ADI-MBR process is a form of activated sludge technology, that uses a submerged membrane barrier to perform liquids/solids separation and reactor biomass retention functions, instead of gravity clarification. This eliminates problems associated with www.esemag.com

sludge settling and separation. The MBR process fits on compact sites, while providing consistent, high quality effluent that can be reused in certain applications. ADI commissioned a 350-gallon ADIMBR pilot plant on-site at Golden Flake, using a small stream of their pre-screened wastewater. The pilot plant operated for three months to demonstrate and evaluate the technology. The system An ADI-MBR system provides a near-absolute barrier to suspended solids, and allows for operation at higher mixed liquor suspended solids (MLSS) concentrations (typically 10,000 to 18,000 mg/l). The system at Golden Flake consists of a pre-aeration tank and two membrane basins, each equipped with doubledecker submerged membrane units (SMU). It is also equipped with aeration blowers, a re-aeration chamber, pumps, instrumentation and controls. The total package includes a control building, with a dewatering press/conveyor system, automatic composite samples, laboratory, office, and PLC systems. Treated effluent is passed through the membranes via a slight suction and then aerated to meet the DO limit prior to discharge to the adjacent stream. Waste activated sludge is dewatered on-site with a screw press, and the sludge cake is removed for disposal. The ADI-MBR system at Golden Flake provides a design hydraulic retention time of approximately one day, and is designed for a daily influent flow rate of up to 400,000 gpd. It treats pre-screened

wastewater with BOD and TSS concentrations that range from 1,000 to 10,000 mg/L, and 200 to 12,000 mg/L, respectively. The new system consistently produces effluent that is lower than effluent discharge limits: <2 ppm TSS, (<30 ppm TSS limit); <5 ppm BOD, (<10 ppm BOD limit); <1 ppm NH3-N (<1.5 ppm NH3-N limit); and >6 ppm DO (>6 ppm DO limit). Up to 250 gallons per minute of highquality effluent is released into the creek, and serves to enhance the downstream riparian environment by improving the oxygenation of water, within the small watercourse. Final effluent produced by the ADIMBR system is clean enough to reuse for certain applications, such as site irrigation. Waste activated sludge from the system is pumped through an on-site dewatering press to reduce the overall sludge volume to 20,000 pounds per week, which is then used for farm fertilization. A maintenance supervisor can completely control the whole system from one location in the plant, or from his home on a laptop. The biggest benefits of the ADI-MBR system are that Golden Flake is no longer discharging primary treated wastewater into the sewer system, and is no longer paying escalating surcharges. For more information, contact Graham Brown, President, ADI Systems Inc. E-mail: gjb@adi.ca

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Wastewater Treatment

New thermophilic digester commissioned at Vancouver's Lions Gate WWTP By Caroline O’Reilly, Leif Marmolejo, Brandon Walker and Christian Brumpton

3D rendering of the Lions Gate WWTP Digester 4 upgrade, showing internal features.

hermophilic anaerobic digestion (TAD) can offer a number of advantages over mesophilic digestion, such as increased volatile solids reduction and pathogen kill, higher specific growth rates, lower biomass yields, and increased biogas production. However, reports on process stability have sometimes hindered the application of TAD in the municipal sector. However, Metro Vancouver has successfully operated TAD at its Lions Gate WWTP since 1990, initially implementing single-stage digestion, followed by a two-stage process. The Lions Gate Wastewater Treatment Plant is owned and operated by Metro Vancouver. It provides primary wastewater treatment to the District of West Vancouver, the City of North Vancouver, and the District of North Vancouver, which have a combined population of approximately 180,000. A four-stage thermophilic digestion process was installed in the mid-1990s at the 580 MLD Annacis Island WWTP. Therefore, considerable process and operational expertise has developed within

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Metro Vancouver, enabling the successful and efficient start-up of the upgraded Lions Gate digester in early 2011. The anaerobic digestion process at the Lions Gate Plant takes place at temperatures between 52oC and 58oC, and, like mesophilic digestion, it is sensitive to changes in temperature, pH, organic loading and other destabilising influences. Maintaining a constant temperature and feed rate, together with thorough mixing, are important in keeping the process stable. Digesters 3 and 4 can be operated in series, with pipework arranged to facilitate either digester operating as the ‘lead’ digester or with both operating in parallel. In both digesters, circulating sludge is heated by pipe-in-pipe heat exchangers. These systems heat feed sludge and replace lost heat (through digester walls/roof, biogas piping, etc.). Biogas is collected and the pressure is boosted for utilization in gas-driven influent pump engines and in a hot water boiler. The engines provide mechanical power for the influent pumps, and waste heat from the engines is recovered for

plant and process utility uses. The boiler and influent pump engine systems have backup natural gas supplies, for periods when biogas is unavailable in sufficient quantity, or quality. Biogas can also be compressed and stored at the plant during periods of low demand. Metro Vancouver retained Associated Engineering to provide design and construction services for the refurbishment of Digester 4.This included installation of a new digester jet mixing system, a new standpipe for scum control, an upgrade of the digester gas system, refurbishment of the sludge circulation/heating system, new digested sludge transfer pumps, a new sludge control building, as well as digester structural upgrades and a new digester liner. The new mixing system in Digester 4 is a Rotamix® jet mixing system with two 50 hp single-speed Vaughan chopper pumps and several nozzle assemblies inside the digester. This system influences process stability, by maintaining homogeneity within the digester, as well as preventing grit, debris and scum accumulation. The newly refurbished Digester 4 was com-

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Wastewater Treatment missioned in June 2011. Start-up planning Metro Vancouver, with Associated Engineeringâ&#x20AC;&#x2122;s assistance, put together a start-up plan that outlined the procedures that would be used to fill, heat, safely and stably introduce raw primary sludge to the digester, and commission the gas system. Planning focussed primarily on safety, with a secondary emphasis on process stability. A detailed step-by-step procedure was developed that included the following: â&#x20AC;˘ Following refurbishments, primary effluent was used to fill the digester and conduct pre-operational checks on all equipment. The digester was then drained to approximately 25%, prior to the introduction of seed sludge. â&#x20AC;˘ Digested sludge from Digester 3 was used as seed sludge. The availability of viable thermophilic seed sludge at the Lions Gate Plant was a significant advantage which facilitated a more straightforward start-up period. â&#x20AC;˘ Digester 4 was completely isolated from all sludge pipework and the gas system, with all digester gas lines purged of oxygen with an inert gas (i.e., nitrogen). â&#x20AC;˘ Digester headspace composition was monitored during the filling process. Regular samples were taken from temporary gas sampling piping which ran from the dome down to ground level, as access to the digester roof was not permitted. Samples were tested for methane (CH4), lower explosive limit (LEL), upper explosive limit (UEL) and oxygen (O2). â&#x20AC;˘ When digestion had been established and once the digesterâ&#x20AC;&#x2122;s headspace was mostly digester gas (i.e., the ratio of oxygen and methane is such that the gas is beyond its upper explosive limit), the gas system was commissioned. â&#x20AC;˘ During digester seeding and feeding, the digestion process was monitored to ensure that adequate performance was nurtured and that the digester was not being overloaded. Parameters monitored daily included temperature, hydraulic retention time, pH, volatile acids and bicarbonate alkalinity. Process monitoring target values were established. â&#x20AC;˘ Digester circulation and heating systems were used during the seeding stage to keep the digester temperature stable at approximately 55°C. â&#x20AC;˘ Digester 4 was filled with an initial bulk transfer of digested sludge (seed www.esemag.com

sludge) from the digested sludge storage tanks, followed by sludge transfers from Digester 3. Thereafter, thickened primary sludge was introduced at a low and controlled feed rate, initially to avoid overloading and shock loading on the digester biomass (i.e., approximately 15% of normal daily loading or approximately 25 mÂł/d). Start-up and commissioning period As planned, the start-up strategy involved headspace gas monitoring as an indicator for gas system commissioning.

Gas composition was determined by the operators on-site with hand held monitors, with representative samples sent for independent laboratory confirmatory testing. After a period of just eight days, the methane (CH4) content of the biogas was >60% and the oxygen (O2) content had dropped to below 1%, which allowed the gas system to be commissioned. Seed sludge was allowed to stabilise and acclimate to Digester 4 mixing and temperature conditions before digester continued overleaf...

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Wastewater Treatment

Aerial photograph of the Lions Gate WWTP showing Digester 4 in the foreground.

feeding with thickened primary sludge (TPS) began. Throughout the start-up period the average total solids (TS) percentage of the feed sludge was 5.9%, with volatile solids (VS) of 91%. Various parameters were monitored by the operations team on a daily basis, including pH, volatile acids (VA), alkalinity, temperature, flow rate, TS% and VS% of the digester feed and digested sludge, gas production, hydraulic load (days) and organic loading (kg/m3.d), with the volatile fatty acids-to-alkalinity ratio (VA:Alk) and pH key indicator parameters used to assess digester stability. Stable operation was recorded with pH value between 7.3 and 7.9, and a VA:Alk ratio between 0.1 and 0.16 with an average of 0.12. Despite some fluctuations early on in digester temperature, the VA:Alk ratio never went above 0.2 and the process remained stable. After a period of 35 days, all of the TPS produced on-site was being pumped to Digester 4. After 61 days, stable operation of Digester 4 had been confirmed, so that Digester 3 could be isolated and emptied for scheduled maintenance. Conclusion The newly upgraded Digester 4 is currently receiving, on average, 167 m3/d of TPS, and is producing 5,412 m3/d of biogas. This will allow Digester 3 to be taken out of service for maintenance and refurbishment. Digester mixing and transfer systems are now fully automated in the WWTPâ&#x20AC;&#x2122;s computerized data acquisition and control system, following internal Metro Vancouver programming. Based on long-term operational experience, thermophilic anaerobic digestion has proven to be a sustainable and robust system, offering a reliable and cost-effective method for sludge treatment and energy recovery at the Lions Gate Plant. The continued use of this renewable energy source is one of the many Metro Vancouver Sustainable Region Initiatives, that promote energy conservation and reductions in greenhouse gas emissions. Caroline Oâ&#x20AC;&#x2122;Reilly, Leif Marmolejo, Brandon Walker and Christian Brumpton are with Associated Engineering. For more information, E-mail: oreillyc@ae.ca

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Water Conservation

Water conservation and the new economy By Sandra Tavares mall and medium size businesses in Canada should and can make a huge difference when it comes to water conservation, especially in their local communities and with their employees. With the new voluntary ISO 26000 guidance document on social responsibility launched in November 2010, businesses now have guidelines and should be aware of them. The document defines one of the benefits of social responsibility as "achieving savings associated with increased productivity and resource efficiency, lower energy and water consumption, decreased waste, and the recovery of valuable by-products. The time to drive home sustainable water management practices for small/medium size businesses is now.” Sustainability consultant, Paul van der Werf, President of 2cg Inc. and My Green Workplace.ca, says that small to large companies are working to improve

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environmental performance. “It’s been interesting to see that during our recent economic times commitment to the stewardship of resources hasn’t faded away,” said van der Werf. “Companies are mindful of researching and finding opportunities to improve their environmental performance with water, waste, and electricity.” He sees many small businesses participating at the local level with incentive programs associated with utilities. Local utilities are raising awareness and small business owners are reaping savings while learning how to manage their water and energy better. Water’s value in Canada is becoming broadly recognized as having the important resource priority that it should. The Walter and Duncan Gordon Foundation, Canadian Water Network, and RBC Blue Water Project recently teamed up for the Blue Economy Initiative. This fall, it will release results of a study

about the economic benefits of protecting Canada’s fresh water, and the economic risks of neglecting the health of watersheds. “Canada’s lakes and rivers hold 9% of the entire planet’s freshwater supply,” says Bernadette Conant, Executive Director of the Canadian Water Network. “It is critical that Canada’s relative ‘abundance’ not make Canadians complacent about water supply, nor divert attention from the critical importance of water quality. Water is not distributed evenly across Canada, nor are its people, industry and environmental needs. Much of Canada’s water is frozen or flows north, away from populated areas. Just one percent of its supply is renewed each year by precipitation. The quality and security of that supply underpin public and environmental health, as well as the economy.” One unique advantage small and continued overleaf...

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Water Conservation medium size businesses have is that they can begin to make long-term changes quickly, that can have positive economic effects in the short term. 1. Begin with a water audit - The best place to begin is with a water audit, as every business will use water in different ways. This can be performed by a professional consultant or possibly the local utility. An audit will assess water consumption, where and when it is used, if leaks are present, offer repair solu-

tions, and will provide conservation guidance. With water rates on the rise, a water audit is a great place to start. 2. Reducing water consumption Every flush, shower and hand wash can reduce water consumption in your business, so employees and contractors can play a conservation role. Consider installing dual flush toilets, which can save nearly 11.4 litres per flush. For all taps, install a low-flow faucet aerator, which will save 2.6 litres of water per

Ministry of Public Works Chief Engineer PS 44 $155,552 (US$ equivalent) Department of Works and Engineering Ref: 5455/82/0072/RA/OS The Department of Works & Engineering seeks a qualified engineer to fill the post of Chief Engineer. Working under the general direction of the Permanent Secretary, the postholder will manage the Works and Engineering Division which provides Highway, Water, Solid Waste collection and disposal, Hydro geological research and monitoring services; vehicle and equipment repair; facility and transport and equipment support services; operation of quarry and asphalt plant; and development impact assessment and work construction management services. Duties include but are not limited to: ˆ  Managing the Works and Engineering Division comprising of approximately 18 professional engineers, approximately 25 technical and administrative employees and approximately 260 clerical and industrial employees. ˆ  Establishing and implementing divisional, managerial and operational policies and guidelines. ˆApproving engineering content of all tenders let by the Government and participating in the review of bids and advise on acceptance or rejection of proposals. ˆ   1EMRXEMRMRK GSRXEGX [MXL WIRMSV SJJMGIVW SJ TYFPMG YXMPMXMIW ERH GSVTSVEXMSRW ERH SXLIV outside bodies pertinent to the operations of the division. Applicants must be qualified for registration in Bermuda as a Professional Civil Engineer and must have a minimum of ten (10) years’ post qualification experience in all aspects of Civil Engineering (structural, highways and water) and preferably have experience in Solid Waste Management, Building Engineering Services design and maintenance and Vehicle Fleet operations. In addition, this experience should include at least five (5) years’ senior management experience in a large engineering firm or government public works environment with demonstrated skills in project management, financial management and human resource management with an industrial work force. This position will be offered on a three (3) year contract term. Any persons wishing to be considered for the position advertised may apply by submitting a completed Government of Bermuda application form (which can be downloaded from www.gov.bm) quoting the appropriate reference number, to: The Secretary of the Public Service Commission, 3rd Floor, Ingham and Wilkinson Building, 129 Front Street, Hamilton HM 12, BERMUDA. email: hr@gov.bm or by fax: 441-295-2858. Closing date: October 31, 2011.

46 | September 2011

minute compared to standard faucets. 3. Rethink outdoors - Using native plants and grasses and harvesting rainwater to irrigate them will cut watering use. Case Study Recently, Levi Strauss & Co. introduced its Water<Less™ jeans. This product innovation was the result of the company looking at its social responsibility. Research showed that, during its life cycle, a single pair of Levi 501 jeans used more than 1,914 litres of water, before it got to the consumer.

The Levi Strauss & Co. example is a life cycle approach to sustainability that is also addressed as an environmental consideration in the ISO 26000 guidance document. By making changes during the manufacturing/finishing process, the company was able to come up with Water<Less™ jeans and reduce its water consumption by an average of 28%. The new finishing process combined numerous wash-cycles and replaced the use of wet stones with dry stones, still giving the product its expected look. To manufacture 1.5 million pairs of Water<Less Jeans, for just one season’s line, added up to a saving of approximately 16 million litres of water. The Levi Strauss & Co. example is a life cycle approach to sustainability that is also addressed as an environmental consideration in the ISO 26000 guidance document. Sustainability is evolving quickly, as a growing number of organizations are demanding sustainability accounting from their supply chains. As such it is a key component to staying competitive. Sandra Tavares is with Tavares Group Consulting Inc., which annually presents a one-day overview of environmental legislation. www.tavaresgroupconsulting.com An on-line way to integrate ISO 26000 into a management system will be available in February 2012 at www.sustainabilitylearningcentre.com Environmental Science & Engineering Magazine


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Instrumentation and Control

Open source software reporting system developed for water and wastewater SCADA systems By Jason Low and Dennis Mutti mplementing effective reporting has always been a challenge with Supervisory Control and Data Acquisition (SCADA) systems. In a typical water plant, the SCADA system consists of a collection of specialized control system hardware, software, wiring, and networks, all working together to look after a multitude of tasks to ensure smooth and orderly operation. SCADA systems look after automated control, alarm management, logging of critical process data, and providing operators with remote access to equipment. Reporting is noticeably missing from the SCADA acronym and continues to be a challenge for system operations. Implementation of effective reporting is difficult for many reasons, including variations in individual user requirements, lack of flexibility in reporting packages, and the need for labour-intensive custom programming whenever a report needs to be added or changed. Licensing, setup, and maintenance costs can also be a challenge for many users. As a radical departure from existing

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reporting software approaches, a new open source reporting package, called e.SCADA.r, is gaining popularity in Ontario’s water/wastewater sector. e.SCADA.r, short for Eramosa SCADA Reporting, is a project that Eramosa Engineering began three years ago. Seeing the need for more advanced reporting tools for the water/wastewater sector, the company began developing the package, using open source software. The software is distributed free of charge for anyone who wants to use it. Users that want additional features added have the option of contracting Eramosa to do the required programming, creating them in-house, or contracting a third party. New reporting features can be added whenever they are needed. Once a new feature is added to the open source code, it is then made available to all other users at no additional cost, including those who have downloaded e.SCADA.r for free. Installation and configuration of the software is straightforward and can be done by either the end user, or with Eramosa’s assistance. Because public water/wastewater util-

ities do not compete with each other, the open source business model works. By emphasizing sharing and collaboration to build a reporting solution, based on the needs of the user community, everyone wins. For smaller municipalities, this is a major benefit because they can get a full featured reporting tool at a fraction of the cost. For larger municipalities, the software gives them the flexibility that allows them to easily make use of and enhance the specialized features that they need. The software is also not restricted by per seat licencing, which allows utilities the flexibility to deploy e.SCADA.r for whichever user group needs it. Similarly, it can be an effective tool for reducing the labour-intensive data requests that many SCADA groups have to contend with. The feature that makes e.SCADA.r easy to use is its web-based graphical interface. Setting up the software generally takes about half a day, but after that the software is entirely user-configurable using a web browser. Data is retrieved from the SCADA system’s existing hiscontinued overleaf...

The feature that makes the software easy to use is its web-based graphical interface. www.esemag.com

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Instrumentation and Control torian server and the reports themselves are configured using the web-based graphical interface. Once a report is configured by a user, the recipe for creating that report is automatically stored on the e.SCADA.r server, so that it can be called up later. Saved report recipes can then be copied and/or adjusted to make new report definitions by using the same web-based graphical interface. Since the process data is coming from the SCADA system’s existing historian server, there is no need to configure/maintain a duplicate reporting database. For users that want a replicated database for reporting purposes, this can be done using the existing historian’s replication technology. As such, there is no need for a specialized second reporting database. The Region of Halton was one of the first municipal water utilities to use the system in Ontario. In their case, they had a large collection of Excel spreadsheetbased reports that were difficult to use and, also, labour-intensive to maintain. e.SCADA.r was the solution they turned to. The software’s user-oriented self-serve

nature meant they could develop the exact reports they wanted. Also, it freed up resources from their internal SCADA team. According to Darren Foster, who was involved with the project in Halton at the time, “the e.SCADA.r reporting system has been a very valuable tool for us on many levels. We have used it to monitor critical plant trends as per the Ontario Ministry of the Environment’s regulation 170 and discovered it to be invaluable for troubleshooting, as well as for plant commissioning. What makes the system so appealing is the ability to easily create and view detailed colour trends, exactly the way you wish to see them, and in the order in which you wish to see them. “Looking at your process-trending from start to finish and having it sent electronically to any remote device (e.g., Blackberry, iPhone, notebook computer, or desktop, etc.) allows everyone to view the process operational “characteristics” from start to finish. This type of accessibility creates a proactive approach that prevents many adverse water incidents from happening. Also, it helps to explain

mechanical and/or instrument failures when they do.” The City of Hamilton is another user of the e.SCADA.r software. In their case, they required a tool for analyzing alarm and event logs. With multiple water and wastewater treatment plants, numerous sewage lift stations, water pumping stations, water towers and other automated parts of their infrastructure, providing tools for analyzing alarm and event logs was critical for their operations and maintenance departments. The City turned to Eramosa to add this feature to the system. e.SCADA.r is now used on a daily basis by the City and integrated into their HMI software. Thanks to this initiative, the alarm and event log analysis tool is now available to other water utilities. Other public utilities in Ontario that are using e.SCADA.r include York Region, Peel Region, the City of Guelph and the Municipality of Centre Wellington (Fergus and Elora). Waterloo Region and Belleville are currently in the process of installing the software. The system has a number of features, which are seeing increasing application

• Scanning of hard copies • Renaming of electronic files • Transmittal creation for work packages • Writing of procedures • Document numbering • CD/DVD burning • Proofreading/formatting of technical documents • French/English translations

Over 20 years of Document Control experience For a free quote and assessment of needs:

Alain Robillard 450-455-8309 RDMDocumentControl@gmail.com 48 | September 2010

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Instrumentation and Control at water/wastewater plants, including ad hoc reporting, multi-pen trend charts, creating and printing daily reports for sign-off, operational reporting, specialized reporting for MOE purposes, alarm/event log analysis, and statistical alarms/reporting to assist with compliance with MOE filter guidelines. Key benefits to users are that it is webbased and requires no configuration on individual user computers. It is centrally managed, so security can be implemented at the server level. Reports are configured using a web-based graphical interface. No custom programming is needed and and the software leverages the site’s existing SCADA historian infrastructure. e.SCADA.r can also generate reports in the form of web pages, PDFs, printouts, and Excel spreadsheets. Furthermore, reports can be configured to be automatically printed and/or emailed on a scheduled basis. Jason Low, B.Sc., and Dennis Mutti, P.Eng., are with Eramosa Engineering Inc. E-mail: mutti@eramosa.on.ca The Region of Halton was one of the first municipal utilities to use the system in Ontario.

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Mining Waste

SART technology coming of age for cyanide recycling By Brad Marchant

BioteQ's application of the SART process recovers up to 95% of cyanide for recycle back to the gold extraction process, improving the environmental performance of the gold operation.

yanide was first used as a means to extract gold from ore in the late 1880s. Fast-forward to the present day and it is currently the most common process for gold extraction, accounting for up to 13% of global cyanide consumption, according to Barrick Gold. A highly toxic substance, cyanide has come under intense scrutiny in recent years, as environmental awareness grows and regulations governing the usage, disposal and destruction of cyanide-laden waste have tightened. In the mining industry, cyanidation is a process in which sodium cyanide solution is applied to a gold heap leach. As it trickles through the crushed ore, the cyanide dissolves gold and other cyanidesoluble base metals. Gold is then recovered from the cyanide solution, and the solution is re-applied to the heap leach. As cyanide degrades over time into less effective leaching compounds, it is then sent to a tailings pond, or to some form of approved destruction process. Gold cyanidation has presented a number of obvious concerns, including the environmental and safety impacts of working with a toxic material. The presence of leachable copper and other base

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metals in gold ore can create a metallurgical challenge by consuming the cyanide. Increased quantities of cyanide are then needed, leading to significant destruction costs. Additionally, the presence of copper in tailings supernatant tends to stabilize cyanide in a form that is harmful to wildlife and less amenable to natural degradation processes, thereby demanding specific and expensive disposal processes. In the past decade and a half, a technology known as SART (sulphidization acidification recycle thickening) has been developed that enables high recycling rates for cyanide. Like any new technology that carries a higher perceived implementation risk than long-established technologies, the process met with resistance at the beginning. However, with successful implementation in the past several years at sites in Mexico and Turkey, SART is now viewed as a viable means to increase gold yields safely and efficiently, reduce associated disposal requirements for cyanide, and improve the environmental footprint of gold operations that generate cyanide waste. Digging deeper for gold The high cost of raw materials and

cyanide disposal technologies have traditionally deterred mine operators from developing ore bodies in which gold occurs with cyanide-leachable base metals. There is now a wealth of un-mined gold deposits in areas rich with cyanide-soluble base metals (e.g., copper and zinc) in North and South America, Asia and Australia. With gold prices at historic highs, mining operations are now taking a second look at options for processing these ore bodies. Part of this reconsideration includes the application of the SART process. SART technology was developed in 1997 by SGS Lakefield and Teck Corporation as a way to reduce the metallurgical interference of copper (and sometimes zinc) in the gold recovery process. It recovers copper from pregnant or barren cyanide leach solution and regenerates the cyanide for reapplication to the gold heap leach. This process can be repeated many times. Its stages are: 1. Sulphidization, to precipitate the copper as copper sulphide. 2. Acidification, to break the coppercyanide coordination complex and liberate the cyanide. 3. Re-neutralization, to raise the pH of the solution with lime to the safe operat-

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Mining Waste ing range (pH 10 â&#x20AC;&#x201C; 11) prior to re-application to the heap leach. 4. Thickening, to densify the resulting solid products (copper sulphide and gypsum), further maximizing the cyanide recovery. When applied successfully, SART can remove up to 99% of the base metal, producing a saleable high-grade concentrate, while regenerating up to 95% of cyanide for recycling to the gold extraction process. It can also improve gold yields and reduce costs for the mine operator. Previously, its use has been limited by two main factors. Additional capital costs are typically associated with SART. These must be balanced with the cost savings of cyanide regeneration, plus the incremental revenue from increased gold yields and the new revenue stream generated from copper recovery. Secondly, early attempts with SART applications met with limited success, due to the complexity of the sulphide precipitation stage of the process. Solving the sulphide precipitation factor While all stages of the SART process are important in removing copper and re-

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covering cyanide for recycle back to the gold operation, the sulphide precipitation circuit and its control are particularly critical, and require specialized know-how in sulphidization. Precipitating metals into a high-grade sulphide product, with good settling and filtration characteristics, has often been a challenge. Specialists such as BioteQ Environmental Technologies, a Vancouver-based water treatment company, have successfully applied their knowledge of sulphide precipitation technologies to SART projects. BioteQ designed and operated the first SART plants in North America and western Asia, and was recently awarded two new projects. The sulphidization process works by introducing a chemical source of sulphide reagent in a contactor tank that contains feed solution to be treated. The conditions in the tank are adjusted to selectively precipitate individual metals as solid metal sulphide particles. These solids are then separated from the treated solution in a clarifier and filtered to remove excess water. By applying a sulphide reagent to precipitate the copper from the leach solu-

tion, gold operations can eliminate copper cyanide complexes in leach residues by recovering the copper as a high-grade concentrate. This removes any potential copper contaminants from the environment. In addition, the process minimizes the amount of waste copper-cyanide solution to be destroyed. There is no question that cyanide will continue to play a significant role in the gold mining process. Therefore, the onus is on the mining industry to demonstrate responsible use when handling, recycling and disposing of cyanide waste. Investment in SART is in its relatively early stages. It is currently being deployed in a small but growing number of projects in South America, Eastern Europe and Asia. However, given its recycling capacity and stability, it promises to play a critical role in enabling gold operations to improve yields, reduce cyanide consumption and waste and mitigate the risks associated with handling and disposal of cyanide. Brad Marchant is with BioteQ Environmental Technologies. For more information, visit www.bioteq.ca

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Guest Comment

How metals and rare earth elements make everyday life possible By Jim Bishop leven years ago, I wrote an article in ES&E about the Periodic Table and some of the elements familiar to most of us. At that time, there were 110 elements on the Periodic Table, of which 40 or so are well known, 30 are radioactive, and 20 others are so rare most people are unaware of them. Another 17 elements make up the “rare earth” elements (REEs), which are not so rare - some are quite abundant in the earth’s crust, and as a group they appear regularly in news reports. These rare earth metals have become somewhat famous over the past few years for two reasons. First, we use them every day. They are key components of such everyday things as CDs and CD players, computers, hybrid cars, and TVs. Second, their importance became even more obvious when we learned that China produces 95% of the global output of these essential elements. The situation became ominous when China’s Commerce Ministry announced it would cut its second half export quota by nearly 75% last year, causing prices for the REEs to soar. Japan, the US, the EU, Canada, and many other countries with advanced high-tech industries, are now desperate to find and develop other sources of these metals. These events have made elements with

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Rare earth metals are key components of everyday things like computers.

bizarre-sounding names, like gadolinium and dysprosium, regular guests in the Wall Street Journal, and they are generating significant excitement in Canada’s mining industry. This is due to the fact that these, and the other 15 rare earth elements, are essential to such common objects as wind turbines, smart phones, computers, iPods, lasers, and diodes. In short, the global high-tech market cannot survive without them. There’s a historical parallel between the sudden mushrooming of the impor-

tance of REEs and those of iron and steel about 160 years ago. Man had found and used very small amounts of iron by 1500 BC. By 1740, iron was being produced at a rate of 20,000 Tons/year, which by means of improved technology (no doubt “high-tech” in its day) grew by a factor of 1,250-fold to 25,000,000 T/yr by 1850. Compare this to steel production in 1850, which was about 60,000 T/yr, produced in small batches of about 22 kg (50 lb) per batch. Enter Henry Bessemer, an Englishman who during the Crimean War had become aware of problems with iron cannons. They sometimes blew up, or otherwise failed, during the heat of battle, due to the brittle nature of the iron. This was a concern to Bessemer, as he had developed a grooved projectile which travelled much further than cannon balls because it developed spin as it exited the cannon. Bessemer was bankrolled by France’s Emperor, Napoleon III, and in 1854 he successfully demonstrated his new weapon. The attending French commandant questioned whether cast-iron cannons could cope with the added stresses imposed by the new projectile. This sparked Bessemer to develop a new, innovative technique for making steel. He blasted air into molten pig iron

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Guest Comment in a crucible called a “converter”. Air is 21% oxygen (O2), which reacted with the excess carbon in the pig iron to form carbon monoxide, which is flammable and produced additional heat, greatly reducing fuel requirements. The O2 also reacted with impurities in the pig iron, like manganese and silicon, forming slag which was skimmed off the top of the molten steel. Bessemer’s process was so successful that by 1870 about 500,000 T of steel was being produced, and by the turn of the century production reached 28,000,000 T. (Steel production in 2010 was 1,414,000,000 metric tons.) Not only was this a high point of the Industrial Revolution, it also heralded the beginning of the science of metallurgy as new steel additives were experimented with to improve the strength, hardness, formability and resilience of steel. These innovations included the addition of limestone (calcium carbonate) to the converter, which enabled Bessemer’s process to convert virtually any iron ore into steel. Soon tungsten was also added, to create tungsten-steel alloys, which extended the lifetime of steel tools by five-fold. Nickel alloys made steel much tougher and resulted in an arms race for European navies eager to clad their warships with this armour-plating. Next, chromium was added to nickel-steel alloys, creating stainless steel which is extremely resistant to corrosion. Today, there are several hundred steel alloys in use, with new ones being developed regularly. Of the 118 or so elements on today’s

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Periodic Table, about 100 are metals. Seven metals, called the Metals of Antiquity, have been known to humans since at least 750 BC: • Gold, ca 6000 BC - jewellery, ornaments, a noble metal. • Copper, ca 4200 BC - weapons, tools, copper sheet.

• Silver, ca 4000 BC - jewellery, ornaments, also a noble metal, often found with lead. • Lead, ca 3500 BC - its ore (galena) was used as eye shadow by the Egyptians, and by 3500 BC lead was being used to make containers and pipes. continued overleaf...

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Guest Comment

Henry Bessemer

• Tin, ca 1750 BC - was known to strengthen copper by 2500 BC, but tin smelting wasn’t common until 1800 BC, in western Asia. Bronze weapons (copper and tin) were vastly superior to copper ones. • Iron (smelted), ca 1500-2500 BC - iron from meteorites was available to ancient peoples as early as 2500 BC. Iron-making did not become a common practice until 1200-1500 BC. Man-made iron revolutionized warfare and agriculture. • Mercury, ca 750 BC - mercury has been found in tombs dated at 1500 to 1600 BC. Its ability to dissolve gold and silver (and many other metals) was a large factor in the development of alchemy. By 750 BC man had learned

how to make liquid mercury. For about 2,000 years no new metals were added, until arsenic was isolated by Albertus Magnus in 1250 AD. Originally, arsenic was used as a pigment, and for murder. Today, it is primarily used to improve the toughness of lead in car batteries, and to improve the sphericity of lead shot. The roasting of antimony was reported by Agricola in 1560; like its cousin arsenic, it is alloyed with lead to improve its hardness and its castability. The 1500s also saw the discoveries of bismuth, zinc and platinum. No other metals were “discovered” until the 1700s when cobalt, nickel, manganese, molybdenum, tungsten, tellurium, beryllium, chromium, uranium, zirconium, yttrium* and titanium were isolated. Only small quantities of laboratory specimens were produced for these metals. There were only 12 metals in common use before 1800: gold, silver, copper, lead, mercury, iron, tin, platinum, antimony, arsenic, bismuth and zinc. An obvious burgeoning technology can be seen in the rapidity with which new metals were isolated and discovered in the 19th Century: 1801 - Niobium 1802 - Tantalum 1803 - Iridium, palladium, rhodium 1807 - Potassium, sodium 1808 - Boron, barium, calcium, magnesium, strontium 1814 - Cerium* 1817 - Lithium, cadmium, selenium

1823 1827 1828 1830 1839 1843 1844 1860 1861 1863 1875 1878 -

Silicon Aluminum Thorium Vanadium Lanthanum* Erbium*, terbium* Ruthenium Cesium, rubidium Thallium Indium Gallium Holmium*, thulium*, scandium, samarium*, gadolinium*, praseodymium*, neodymium*, dysprosium*, ytterbium* 1886 - Germanium 1898 - Polonium, radium 1899 - Actinium * Denotes rare earth elements Of the 42 metals discovered in the 19th Century, the most important (following steel) was aluminum. It had been isolated from bauxite in 1825, but in tiny amounts. By the second half of the century Al was both a rare and a precious metal. Russia chose aluminum for its coinage over platinum, to demonstrate the country’s technical expertise. Napoleon III of France had a set of aluminum tableware, for use by preferred guests. Others had to make do with gold. Aluminum’s mystique ended around 1886 when a French entrepreneur (Paul L.T. Heroult) and another in the US (Martin Hall) independently discovered the electrochemical process that led to commercial production of aluminum metal. The companies formed by these

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Guest Comment

Bessemer’s innovative technique for making steel, blasted air into molten pig iron.

This was the first solid-state crystal that could act as a switch, plus it amplified the input voltage. It was a windfall for Bell and its parent company, AT&T, and it was the beginning of the end of the large, energy-heavy vacuum tubes that had been used for electronic amplification for decades. It was also the end of electromechanical and operator-intensive switches, used to direct telephone calls. This was the start of the microelectronic revolution, and its pace has been accelerating ever since. As telephones, radios, and other electronics became faster, more efficient and smaller, increasing efforts were being made to fully understand the properties of many of the metals that had been discovered from 1800 to the1950s. This included several of the lanthanides, which are elements 57 to 70 in the Periodic Table. These 14 elements, plus scandium, yttrium, and lutetium, are historically classified as rare earth elements. As China continues to slash REE exports to satisfy its domestic demand, the price of them will continue to rise in the rest of the world. Eventually, the price

reaches the point where exploration and mining for REEs becomes financially attractive, and this is happening in numerous locations today. East Africa, several US states, Brazil, India, Sweden, Norway, Russia and Canada have deposits of REEs, and mining/exploration companies able to extract them. Canada is home to 56% of the potential REE deposits outside of China. Ontario’s Mineral Deposit Inventory documents more than 200 known REE mineral occurrences (MNDM, March 2011). Ongoing exploration in the province’s Ring of Fire and elsewhere, including established REE properties in Elliot Lake, could evolve into new REE-based production and manufacturing bases. It could even put Canada in a prime position for the creation and development of environmentally sensible, energy-smart, futuristic products for use in global high-tech markets. Jim Bishop is with Stantec in Mississauga, Ontario. E-mail: jim.bishop@stantec.com

experimenters eventually became Alcan and Alcoa. Production of zinc and copper saw similar advances in the 1800s, as did titanium when commercial production was developed in 1950. The five most commonly used metals today are iron, aluminum, copper, titanium and zinc. Each of these metals are present in objects we use every day, such as cars, appliances, electronics, and so on. But while they’ve been used this way for many decades, their more obscure cousins - the rare earth metals - have only been in our everyday objects for a few years, or decades. The rare earths have become known to us because of the miniaturization of electronics, which only started in 1947, when the first transistor was created. This was made by two researchers at Bell Telephone Laboratories who became Nobel Award winners. They used a piece of germanium, on which two tiny specks of gold had been placed. When the gold touched the germanium, and a voltage was applied to one of the gold contacts, current flowing to the other contact through the germanium was increased. www.esemag.com

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Wastewater Treatment

Bowen Island WWTP upgrade presented unique challenges ocated in British Columbia, the Municipality of Bowen Island’s Snug Cove wastewater treatment plant was built by ECOfluid Systems in 1999. The original plant consisted of two upflow sludge blanket filtration (USBF) bioreactors, each designed to treat 80 m3 of wastewater per day at 185 mg/l BOD, or 14.8 kg BOD per day. Permitted ocean outfall effluent discharge parameters were relatively undemanding: 45/45 mg/l respectively for BOD and TSS, and an acute 96 hour LT50 fish bioassay test. Plant configuration was very basic, consisting of a pump station and the USBF bioreactors only. No post-filtration was employed. All effluent discharges were significantly below levels permitted and nutrients, such as nitrogen and phosphorus, were reduced. However, in the summer of 2005, increased stress on the plant was observed during the high tourist season, due to biological overloading. Plant expansion and upgrade In 2009, after securing provincial and federal grants, the Municipality embarked on a plant expansion and upgrade. Objectives of the approximately $2.3 million project included: • Installation of new mechanical head-

L

1999 Snug Cove WWTP (original installation).

works. • Plant expansion to double its hydraulic and biological capacity, with a provision to triple it in the future. • Incorporation of tertiary treatment, which would allow reuse of treated effluent for irrigation, and/or dual plumbing applications. This would require effluent to meet the municipal sewage regulations

for BOD and TSS of respectively less than 10 mg/l, turbidity of 2 NTU (avg.), fecal coliform of 2.2 CFU/100 ml (avg.), ammonia of less than 1 mg/l, and total nitrogen of less than 20 mg/l. • Waste sludge dewatering, to reduce the cost of ‘off island’ trucking and its inherent carbon footprint. • Incorporation of a pressurized outfall

The new headworks (left), process building, and sludge dewatering unit and bin. 56 | September 2011

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Wastewater Treatment

New membrane filtration tank with roof.

New USBF bioreactor 3.

station. • Pilot receiving facility to evaluate septage processing in the USBF bioreactors. Headworks As a part of the upgrade, all incoming sewage flows were diverted to a new inclined mechanical auger screen. It was installed in a concrete channel that leads to

a refurbished influent pump station. The all-weather IPEC screen collects and compacts screenings into a continuous bagging system. USBF bioreactor A new bioreactor was installed adjacent to the two existing ones. The sludge blanket filter (SBF) of the bioreactor is

fabricated from epoxy-coated steel and provides separation of the anoxic and aerobic compartments. The bioreactor’s anoxic compartment was equipped with a new submersible mixer, designed to provide conditions for mixing of the influent sewage with activated sludge recycled continued overleaf...

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Wastewater Treatment from the bottom of the SBF. This provided the necessary conditions for enhanced nitrogen removal, by nitrification/denitrification processes, and phosphorus removal by biological â&#x20AC;&#x153;luxury uptakeâ&#x20AC;?. Tertiary treatment Tertiary treatment consists of membrane filtration, UV disinfection, chlorination and reclaimed water storage. For filtration, Mitsubishi immersed hollow fibre membranes were selected. They were installed within a separate tank, receiving effluent pre-filtered by the sludge blanket filter of the USBF bioreactor (<10mg/l TSS). The configuration not only results in safer multi-barrier twostage filtration, but flux rate increases, fouling decreases, and energy input is reduced. Also, the biological process and the membrane filtration are separated, so each can be better optimized. Membrane filtered effluent is transferred via a self-priming centrifugal pump to a Trojan UV disinfection system which is housed in a stainless steel channel located in a new process building. Finally, tertiary effluent is transferred into

a new PVC-lined reclaimed water storage tank. The tank is provided with a chlorine make-up circulation loop to maintain minimal residual chlorine when required. Project challenges ECOfluid was aware that the upgrade of the existing facility presented many unknowns and taking on the project with a firm budget presented a significant risk. However, the design-build model provided flexibility and allowed the company to quickly deal with on-site construction issues. With preliminary design/engineering completed in September 2010, construction began a month later. As expected, many project challenges presented themselves during construction. The first challenge was that the project was located on an island, only accessible via a 30 minute ferry ride. Managing larger deliveries, sub-trades and on-site personnel was further complicated due to the small and compact site. The weather brought another challenge, as an unprecedented wet winter and spring led to many construction delays. Another challenge was to carry out all work while keeping

the existing facility in operation. Adding new equipment and components, and bringing them online, without shutdowns and interference with the existing operation, proved demanding. Initial design work, by Kerr Wood Leidal and ECOfluid, began in early 2010. In August ECOfluid was awarded the contract to execute the project. Substantially completed in June 2011, the new facility has met all objectives. The most important of these were an immediate increase of the hydraulic and biological capacity of the plant and the improved quality of its effluent. The USBF-MBR configuration has also provided the municipality with the options of reusing treated effluent for irrigation at a nearby regional park, and/or for future dual plumbing applications. For more information, E-mail: jhebner@ecofluid.com

For over two decades, the SPD Sales team has remained dedicated to the promotion; supply and support of instrumentation and chemical feed products for the process control market. Our highly trained and qualified personnel provides full technical application and product support to industries and municipalities, putting forward the highest quality products and instrumentation solutions for our clients. We build strong, long lasting partnerships with our clients by providing comprehensive product support and calibration services. We represent many leading companies, including:

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Stormwater Management

Edmonton’s airport upgrades its deicing fluid treatment system By Mark O. Liner irports and airlines are required to protect nearby streams and water bodies from wintertime deicing activity. Such is the case with Edmonton International Airport (EIA) and Whitemud Creek, which runs along its western side. In 2000, the airport constructed a subsurface flow wetland to provide treatment of glycol, and other deicing chemicals, found in the stormwater during spring melt. Addressing a need to accommodate increasing air traffic and associated deicing operations, EIA initiated an upgrade of the wetland system to increase treatment capacity and operational flexibility. Through reconfiguration of the hydraulics and the addition of aeration, the full-scale system has the capacity to provide up to 4,000 m3/d of treatment at a loading of 711 kg-BOD/day. Associated Engineering led the design

A

team with support from Naturally Wallace Consulting. Stuart Olson Dominion is responsible for construction management of the project. Subcontractor Nelson Environmental is responsible for the majority of construction and equipment.

be used for deicing a plane, BOD requirements for treatment become very high. Each airport has different circumstances that lead to varying strategies for aircraft deicing fluid (ADF) management. Those with centralized deicing

Addressing a need to accommodate increasing air traffic and associated deicing operations, EIA initiated an upgrade of the wetland system to increase treatment capacity and operational flexibility. The project is currently under construction, and will be commissioned this November. Background Aircraft are typically deiced with glycol-based solutions, such as propylene glycol (PG). As over 758 litres of PG can

pads are able to capture and funnel the majority of deicing fluid as a concentrate, which makes it easier to dispose of it or recycle. With at-gate deicing, airports usually capture and hold glycol-rich stormwater in larger storage basins, and continued overleaf...

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Stormwater Management

The upgrade of EIA’s glycol treatment system included a Forced Bed Aeration system.

treat or discharge it as time permits. EIA uses a combination of approaches that include sewage plant discharge of high strength concentrate, and storage and on-site treatment of low strength

stormwater. Previous design At EIA, ADF-contaminated snow is collected and stored to manage the release of glycol from the airfield. Glycol and

other plane and pavement deicing compounds are channeled to the 91,000 m3 Gun Club Pond, located northwest of the airport. BOD concentrations in the pond can be as high as 600 mg/L during spring melt, so the water requires treatment prior to discharge to Whitemud Creek. The existing wetland treatment system consists of 12 square gravel-filled beds arranged in six trains of two cells each. Each bed is 43 m x 43 m, with a gravel depth of 0.6 m. Water from the Gun Club Pond is delivered, via a submersible pump, with measured flows of between eight and 28 litres per second. Flow rate is governed by the hydraulic head difference between the pond and the wetland beds. System upgrade design The system upgrade is designed to provide over 711 kg-BOD/d of treatment, and to allow increased flow rates as the concentration of the BOD drops during spring melt. It includes reconfiguration of two existing treatment trains initially and a third train in the future. The first cell of each of the upgraded trains has been modified to a vertical flow config-

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Stormwater Management uration, and incorporates patented Forced Bed AerationTM. The second cell in the train has been reconfigured as a surface flow wetland for polishing of the effluent. Aggregate from the second cell was relocated to the first cell, to increase the aggregate and water depth to 1 metre. The depth of aggregate in the second cell is 0.3 m, with a total water depth of 0.6 m. With the addition of aeration and nutrients, the upgraded system can provide up to 10 times more treatment in half the footprint of the existing wetland system. Aeration and nutrient systems are designed so that levels can be adjusted based on influent concentrations. Converting to vertical flow removes the hydraulic constraints previously experienced with the old horizontal flow wetlands. An upgraded lift station also provides substantially more flexibility, when meeting the aberrant flows of spring melt. Finally, incorporation of a recycle system, within each of the first cells, permits expedited start-up in the spring. Adding aeration to enhance treatment

As over 758 litres of propylene glycol can be used for deicing a plane, BOD requirements become very high.

The aeration system uses specially manufactured tubing that is installed beneath the gravel layer. Two positive displacement blowers, each sized to deliver 1,500 SCFM, supply air.

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Stormwater Management square metre. This provides efficient aeration of the gravel bed, and results in robust growth of aerobic bacteria, that are responsible for the degradation of pollutants in the stormwater. Similar aeration systems have been employed for the glycol treatment systems at London Heathrow and Buffalo Niagara International Airport. In each case, providing uniform aeration is central to increasing the capacity of treatment, and meeting the highly variable oxygen demands associated with deicing activity. Theory of operation After each winter, the concentration of BOD will be measured in the Gun Club Pond to determine the amount of total organic mass that needs to be treated. A calculation of supplemental nutrients will be undertaken to determine the amount of nutrients that are required to achieve healthy bacterial growth. A nutrient solution will be fed to the pond and mixed. After this, an initial batch of glycolcontaminated stormwater will be introduced to the drained beds to begin the

62 | September 2011

initial â&#x20AC;&#x153;acclimatizationâ&#x20AC;? phase. Blowers and recirculation pumps will be started and the contents of the bed will be aerated and re-circulated, until there is evidence of bacterial activity and BOD levels drop to acceptable discharge levels. At this point, the first bed is acclimated and the influent pumps will be turned on to provide automated discharge into the beds. Treated stormwater from the first bed will flow by gravity to the second bed, where it will be polished further and ultimately discharged to Whitemud Creek. As the Gun Club Pond is lowered, periodic sampling will determine the level of BOD in the system, and the influent pumping rate will be increased relative to the decrease in BOD concentrations. This will maintain a constant mass load to the beds, within the capabilities of the treatment system. Once the Gun Club Pond is empty, discharge into the treatment system will stop. However, aeration of the beds will continue. With no more influent or effluent, aerobic bacteria generated during the

treatment period will be starved and undergo in situ aerobic digestion. Aeration and recirculation of the beds will continue for two weeks and then be shut off to promote evaporation and plant uptake of nutrients. Prior to the onset of winter, the beds will be drained to minimize ice formation. Conclusion The upgrade of the EIA glycol treatment system demonstrates how Forced Bed Aeration can be used to improve an existing wetland system. Reconfiguration of the existing cells and the addition of aeration greatly increase the capacity and operational flexibility of the system. Innovative engineering allowed EIA to expand capacity, by using existing infrastructure. In doing so, the airport can continue to meet its environmental protection obligations. Mark O. Liner is with Naturally Wallace Consulting. E-mail: mark.liner@naturallywallace.com

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Spill Management

Analyzing a complex oil spill at an Ottawa hospital By Dan McNicoll, Mark McCalla, Kathy O’Neill and Philippe Marleau

n January 2009, a large furnace oil spill occurred beneath the Montfort Hospital which is situated in the east end of Ottawa, Ontario. During a $300M expansion program, a 50,000 litre underground storage tank (UST) was installed just north of the “D Wing” building of the hospital complex. The UST supplies furnace oil to the hospital’s heating plant. A remote fill station was located approximately 20 m from the tank. During final construction activities, the remote fill pipe for the furnace oil tank was inadvertently severed without being repaired. In January 2009, during a period of peak demand, the tank was filled five times before strong petroleum odours were noticed by the basement staff. The hospital immediately evacuated the affected staff and retained exp Services Inc. (exp) to determine the source of the furnace oil odours and to direct emergency response measures. Emergency response As part of the emergency response program, indoor air samples were collected, portable air scrubbers were brought in, furnace oil fill procedures were immediately ceased, and an investigation was conducted to determine the source of the furnace oil odours. After some remote video camera work, a break in the pipe was confirmed. The furnace oil UST and piping was subsequently removed and 1,200 tonnes of furnace oil impacted soil were removed beneath the pipe break and around the UST. Unfortunately, a significant amount of furnace oil was determined to have migrated directly beneath D Wing. Interior sumps and sewers were inspected and temporary oil recovery/groundwater treatment measures were immediately implemented, where necessary. Subsurface Investigation Exp conducted a detailed forensic investigation to determine the most likely cause of the pipe break and calculated that approximately 22,000 L of furnace oil had leaked into the subsurface environment. Due to pending legal actions

I

64 | September 2011

Aerial view of hospital.

by the insurer, the cause of the pipe break cannot be disclosed at this time. A comprehensive subsurface investigation was performed to delineate the extent of the subsurface impact. In total, 28 interior and exterior overburden wells and 33 interior and exterior bedrock wells were constructed on the site, using both conventional and unconventional drilling techniques. The site was found to be underlain by approximately 1 - 2 m of granular fill material, overlying native silty clay, and silty glacial till. The till, in turn, is underlain by Ottawa Formation limestone bedrock at depths ranging from 4 m to 10 m below grade. A major geological fault also exists beneath the site and is thought to pass directly beneath the affected D Wing building. Bedrock groundwater flow direction was found to be from northeast to southwest, or from the neighbouring residential houses towards the hospital. The overburden groundwater regime was found to be discontinuous and, where present, was calculated to be flowing to the south under a gradient of approxi-

mately 0.03 m/m. The furnace oil plume was found to have migrated beneath 75% of the D Wing building footprint and towards the adjacent off-site apartment building property, located approximately 50 m to the south. Large concrete earthquake ballast slabs situated beneath the building served to channel and funnel the oil, making its delineation (and subsequent recovery) very difficult. Stakeholders The hospital’s medical records, decision support, and medical affairs departments are located directly over the area affected by the spill. Health and safety issues for these departments and others located in the new wing needed to be addressed throughout the remediation process. Measures are still ongoing to ensure that all concerns are met. Hospital support services such as Facilities and Occupational Health and Safety were key partners in the management of the situation, as was the Montfort Hospital Governance. Another important stakeholder was the hospital’s major tencontinued overleaf...

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Spill Management

Tank removal.

ant, the Department of National Defense. The hospital is surrounded by a neighbouring community whose residents have their own well and septic systems. Monitoring measures were put in place and regular community communication sessions were offered to address their concerns. A residential apartment building is located directly to the south of the hospital, so owner and resident concerns regarding the spread of the spill onto their property needed to be addressed on an ongoing basis. Regular communication with various ministries including Ontario Health and Long Term Care, the Ontario Ministry of the Environment (MOE), The Technical Standards and Safety Authority, the City of Ottawa and other governing bodies, had to be addressed. Because the project was not fully completed at the time of the spill event, coordination was needed with the general contractor and prime consultant. Finally, as the ultimate payer, the insurance company, the insurance adjuster, and their broker representative were included in all aspects of communication and overall management of the situation. Remedial options analysis Based on the findings of the subsurface investigation, a Remedial Options Analysis (ROA) was performed to select 66 | September 2011

the most appropriate solution. The ROA included a comprehensive review of available remedial technologies; the selection of four preferred technologies or options; preliminary cost estimates for each option; estimates of the anticipated operating period; and, an estimate of hospital staff displacement duration. The ROA focused on a phased approach to the overall site remediation program. The first phase was concentrated on the recovery of furnace oil product. The second phase consisted of the establishment of the final remediation objectives (i.e., background, potable/ non-potable water, or site specific criteria). The third phase, if required, would be to examine additional treatment technologies that could be used to reduce the length of time required to attain the desired final remediation objectives once all of the furnace oil product had been recovered (i.e., the addition of surfactants, oxygen releasing compounds, etc.). Based on the site conditions, it was agreed that the provincial potable groundwater criteria would be used as the remediation criteria. The four remedial options that were ultimately selected for more detailed costing were 1) natural attenuation; 2) multi-phase extraction (MPE); 3) partial excavation and MPE; and 4) complete

excavation. The preferred remedial option that was ultimately selected was MPE. MPE remediation system Exp designed the multi-phase extraction system to recover free phase furnace oil; petroleum impacted groundwater; petroleum vapours beneath the building; and to enhance biological degradation of the residually impacted soil beneath the building that could not be removed. The MPE system involved the installation of 16 interior recovery wells within the basement of the building and 13 exterior recovery wells along the southern property boundary to prevent off-site contaminant migration. All of the recovery wells are equipped with pneumatic submersible pumps, which recover oil, water and vapours from beneath the building and direct them to an exterior, on-site facility for treatment. Piping from each recovery well is directed beneath portions of the floor, within wall cavities, and above the ceiling. Installation of this piping distribution system within an operating hospital required extensive planning, coordination, security, installation of elaborate infection control barriers, and testing to demonstrate containment and treatment of petroleum vapours within the barriers prior to their removal. Pilot and full scale remediation Prior to the design of the full scale MPE system, a readily available, small packaged MPE unit was used on-site in order to provide some immediate control of the subfloor vapour emissions; collect and recover some of the furnace oil product; confirm the appropriateness of using MPE at this location; obtain site specific hydraulic conductivity and air permeability measurements; assist in sizing of the vacuum blowers, water pumps, oil/water separator, etc.; and, assist in determining the volumes of water and air that needed to be withdrawn from the subsurface for regulatory permitting purposes. The pilot test successfully demonstrated that a full scale MPE system would be effective at this location. Sitespecific soil parameters were calculated and used in the design of a full scale, permanent MPE system. The final design included three large vacuum blowcontinued overleaf...

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Spill Management

Treatment System.

ers, 29 pneumatic submersible pumps, a large compressor, an elaborate sediment filtration system, liquid and vapour phase granular activated carbon, an oil/water separator, and a sophisticated control system with remote access and alarm capabilities. The full scale MPE remediation system was activated in January 2011 and has proven to be very effective. To date, approximately 60% of the 22,000 L of furnace oil product spilled has been recovered and petroleum vapour concentrations within the hospital have been reduced to acceptable levels. Initial capital costs for the remediation system and emergency response measures were in the range of $8 to $10 M, and the monitoring and maintenance costs for the anticipated 10 to 15 years of operation are expected to be in the range of $10 to $15 M. Indoor air quality Immediately after learning of the spill event, hospital staff became very concerned over their exposure to potentially hazardous air contaminants associated with the oil. In order to ensure their health and safety, the hospital engaged exp to conduct indoor air quality monitoring and provide recommendations on other mitigative measures that could be employed. 68 | September 2011

An indoor air monitoring program was implemented and is presently being conducted on an ongoing basis, including the regular collection of indoor air samples for laboratory analyses of volatile petroleum hydrocarbons (PHC) and real time, direct read, monitoring of total volatile organic compound (TVOC) levels. In addition, two sophisticated, real time TVOC monitors were installed in the D Wing basement, which provide continuous readings and record all readings on a data logger. These two units are equipped with audio/visible alarms in the event of elevated readings. Although, at present, there are no Canadian or US standards for TVOC, the Health Canada guideline indicates target and action levels of 1,000 and 5,000 μg/m3, respectively, are being discussed. The European Community indicates that, at a TVOC exposure over 3,000 μg/m3, symptoms such as odours, irritation, and discomfort may occur and complaints may be expected. Since the operation of the pilot, and subsequent full scale, remediation system, concentrations of TVOC have decreased and have remained stable in what is considered to be a normal range. In addition to the field measurements, indoor air samples are collected

for laboratory analyses at nine locations every three months. Sample locations are in rooms where there were previous complaints of odours, in unoccupied rooms awaiting occupancy, and in areas situated above the oil plume. Analytical results are compared to Ontario Ministry of Labour (MOL) Occupational Exposure Limits and calculated MOE risk based target levels for the tested parameters. Over the last year, all measured parameters were below these levels. Benzene concentrations ranged from <1 μg/m3 to 3.6 μg/m3, which is much less than the MOL permissible occupational exposure limit of 1,600 ug/m3. Lastly, exp recommended that the ventilation system in the basement of the D Wing be adjusted to increase the air pressure so that it is positive with respect to the subfloor. With the negative subfloor pressure created by the MPE system, air flow within the basement is in a downward direction. This prevents potential vapours from migrating upwards into the hospital environment. To monitor air flow direction, there are currently four manometers installed within the basement floor that record and log the pressure difference between the office environment and the subfloor regime. MOL investigation and findings The local Ministry of Labour office conducted a comprehensive investigation in order to determine whether the remediation system and monitoring programs were sufficient to safeguard staff from being exposed to unacceptable health risks associated with the oil spill. After their review, the MOL concluded that the site remediation system has proven to be effective and worker exposure to airborne petroleum hydrocarbons is acceptable. There is no evidence to indicate that a chemical hazard presently exists for workers at the hospital, due to exposure to airborne petroleum hydrocarbons associated with the fuel oil spill.

Dan McNicoll, Mark McCalla, Kathy O’Neill and Philippe Marleau are with exp Services Inc. For more information, E-mail: dan.mcnicoll@exp.comw

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Kinecor and Peacock are now proud to be Wajax Industrial Components We are a nationwide distributor of industrial components providing technical solutions and services to all major industries across Canada. Over the years our company has forged itself through the contributions of numerous businesses, resulting in our present-day expertise. Kinecor, one of Wajax Corporationâ&#x20AC;&#x2122;s three divisions, will now share the Wajax name. The Wajax company has existed for over 150 years and is largely recognized within the industrial sector of the Canadian economy. Kinecor and Peacock will begin operating under the Wajax Industrial Components name on December 31st, 2011. Only the QDPHRIRXUIDFLOLWLHVÂąKHDGRIÂżFHGLVWULEXWLRQFHQWUHVDQGEUDQFKHVÂą will change; their locations will remain the same.

1.866.546.3267 www.wajaxindustrial.com


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Wastewater Treatment

Alternative WWTP project delivery model is key to improving Mumbai’s quality of life By Sanjay Devnani and Vincent Nazareth lternative project delivery models are allowing Mumbai, India, to implement urgently needed wastewater treatment and conveyance upgrades. Most of the city’s existing sewage, which averages 3,258 million litres per day (ML/d) and peaks at 6,624 ML/d, discharges untreated into local watercourses and the Indian Ocean. This degrades the local environment and endangers public health. The consortium of R.V. Anderson Associates Limited, and Mott MacDonald Limited from the UK, was retained by the Municipal Corporation of Brihan Mumbai (MCBM) in 2007 to undertake capital upgrades to Mumbai’s wastewater system. A changing regulatory environment and a decision from MCBM to immediately implement works that were originally supposed to be deferred, greatly changed the scope of work. The current scope includes $1 billion (CAD) worth of capital upgrades, including one new treatment facility; installation of primary and secondary treatment at seven wastewater treatment facilities, ranging from 37 ML/d to 849 ML/d; sludge stabilization and biosolids management facilities for all eight plants; 10 new sewage pumping stations; 19 km of new tunnel sewers; 25 km of sewer rehabilitation; and 10 km of transfer tunnels to a new 5 km ocean outfall. A procurement strategy developed by the consortium retained to undertake the priority works determined that the WWTPs would be best procured through alternative project delivery models, specifically design-build-operate. The design-build-operate model offers contractors flexibility in design with opportunity for innovation, which could result in significant capital and operations cost savings. More importantly, it gives MCBM time to recruit and train staff, while transferring design, construction, and operational risk to the contractor. Mumbai’s operations staff have limited experience with primary or secondary treatment processes. Design-build-operate will also allow the facilities to become

A

70 | September 2011

Map of Mumbai sewage disposal works project stage 2 priority works.

Rendering of the 37 ML/d Colaba Wastewater Treatment Plant.

operational more quickly, as well as accelerate amelioration of past environmental impacts. The Request for Proposal for the project’s first design-build-operate contract, with a 15-year operations and maintenance requirement, will be released later this year. It will be for expanding and upgrading the 37 ML/d Colaba WWTP, which is Mumbai’s smallest treatment facility. This plant will be constructed in a highly built-up area. It will set the standard for treatment plant design and operations quality, and allow the issues to be identified and addressed, that could be of higher risk when undertaking larger projects. Once Colaba is underway, work will begin on the next plants: Ghatkopar (503

ML/d), Bhandup (323 ML/d) and Lovegrove (493 ML/d). All design-build-operate contracts will be based on the guide from the International Federation of Consulting Engineers (FIDIC)’s Gold Form Conditions of Contract. Using internationally accepted forms of contract is expected to give contractors confidence in bidding on the project. It is anticipated that bids will be received from all over the world, which should provide for a high degree of innovation. Sanjay Devnani and Vincent Nazareth are with R.V. Anderson Associates. For more information, E-mail: tcarey@rvanderson.com

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Ranging from 2.7 HP to 536 HP, ABS EffeX pumps provide outstanding benefits for optimal lifecycle economy, including long-term reliability, greater energy savings, excellent rag handling, and future-proof design.Visit www. abseffex.com for more information. Tel: 800-988-2610, Fax: 905-670-3709 E-mail: info.abs.ca@cardo.com Web: www.absgroup.ca ABS Group

Package Treatment System ACG Technology’s package treatment system offers performance and durability. It provides sewage treatment within a small footprint. Aeration, mixing and settling can be accomplished in compact, easily transported ISO containers, ideal for remote locations. Provides flexibility of adding future parallel units, an economical means of meeting the needs of any growing sewage loads. Tel: 905-856-1414, Fax: 905-856-6401 E-mail: sales@acgtechnology.com Web: www.acgtechnology.com ACG Technology

APU offers 87 degrees

Biosolids management

American Public University (APU) has 87 online degrees. Our tuition is far less than other top online universities so you can further your education without breaking the bank. Learn more about one of the best values in online education. Web: www.studyatAPU.com/ESE.

American Water provides beneficial reuse of biosolids; advanced technologies - Class A biosolids; mobile dewatering; digester, reactor, tank and lagoon cleaning; confined space entry; treatment plant by-pass; vacuum and haulage services; custom, mobile screening; and free assessments and quotations. Tel: 800-846-2097 E-mail: terratecsales@amwater.com Web: www.terratec.amwater.com

American Public University

American Water

Phoenix Underdrain System

• Optimizes all types of filters • Extremely low profile; lowest available • Manufactured from corrosion-resistant stainless steel • Variable custom orifice sizing • Custom hydraulic design • Guaranteed uniform air scour distribution • Rapid, low-cost installation Tel: 403-255-7377, Fax: 403-255-3129 E-mail: info@awifilter.com Web: www.awifilter.com AWI

www.esemag.com

Coalescing oil/water separators ACG Technology’s coalescing oil/ water separators are available in carbon steel, stainless steel, FRP and polypropylene construction. Standard systems include air-operated diaphragm pump, air filter and floating skimmer. Adjustable weir and skimmer height provides optimal oil removal and minimal disposal volume. Standard range is 1 to 50 GPM. Tel: 905-856-1414, Fax: 905-856-6401 E-mail: sales@acgtechnology.com Web: www.acgtechnology.com ACG Technology

Phoenix Panel System

• Upgrades and optimizes all types of filters • Installs directly over existing underdrain system • Eliminates the need for base gravel layers • Improves backwash flow distribution • Provides longer filter runs and lower turbidity effluent Tel: 403-255-7377, Fax: 403-255-3129 E-mail: info@awifilter.com Web: www.awifilter.com AWI

Lone worker protection

Electronic road flares

The new Grace G.E.M. MS900 Employee Monitor solves the problem of employees working alone in remote locations. The worker wears a small battery-operated motion detector with a panic button. If a worker is incapacitated, the motion detector automatically goes into alarm and a signal is sent up to 3/4 mile to the Grace receiver. An injured but conscious worker uses the panic button to summon help. Tel: 800-265-0182, 905-949-2741 Fax: 905-272-1866 E-mail: info@cdnsafety.com Web: www.cdnsafety.com Canadian Safety Equipment

EFLARE, the new electronic road flare, eliminates the need for hazardous pyrotechnic road flares with their toxic fumes and potential fire hazard. The EFLARES have 360 degree high visibility LED beacons with flash or steady-on capabilities in orange, red, green, blue and white. They are intrinsically safe, with up to 80 hour battery life and low battery indicator. Tel: 1-800-265-0182, 905-949-2741, Fax: 905-272-1866 E-mail: info@cdnsafety.com Web: www.cdnsafety.com Canadian Safety Equipment

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Product & Service Showcase

ABS pumps range


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Corrosion protection

Denso Petrolatum Tapes

Denso Bitumen Mastic is a high build single component, cold applied liquid bituminous coating that is used to provide economical corrosion protection on buried pipes, valves, flanges and underground storage tanks. Denso Bitumen Mastic is self-priming, VOC compliant and can be applied by brush, roller or spray. Tel: 416-291-3435, Fax: 416-291-0898 E-mail: blair@densona.com Web: www.densona.com Denso

Proven worldwide for well over 100 years, Denso Petrolatum Tapes offer the best, most economical, long-term corrosion protection for all above and below ground metal surfaces. Requiring only minimum surface preparation and environmentally responsible, Denso Petrolatum Tape is the solution to your corrosion problems in any corrosive environment. For applications in mines, mills, refineries, steel mills, pulp & paper, oil & gas, and the waterworks industry. The answer is Denso! Tel: 416-291-3435, Fax: 416-291-0898 E-mail: blair@densona.com Web: www.densona.com Denso

P roduct & Service Showcase

New liquid hypochlorite injection system Fluid Metering, Inc. has introduced their NEW Chloritrol™ valveless metering system for accurate, maintenance-free injection of liquid sodium and calcium hypochlorite for purification of municipal drinking water and other sanitizing operations.The Chloritrol has been field tested in very demanding applications, and demonstrated that it exceeds performance expectations. Tel: 800-223-3388, 516-922-6050 E-mail: pumps@fmipump.com Web: www.chloritrol.com Fluid Metering

Next generation water sampler The new CSF48 water sampler from Endress+Hauser sets the benchmark in water quality monitoring. Choose between vacuum or peristaltic pumping, and multiple sampling routines. Opt for the two industrial digital sensors (expanding to eight in future) and connect to the SCADA with the latest communications protocols. This is a complete monitoring and collection solution for today’s industrial requirements. Tel: 905-681-9292, Fax: 905-681-9444 E-mail: info@ca.endress.com Web: www.ca.endress.com Endress + Hauser

Ozone systems

Vortex mixing system

The JetMix Vortex Mixing System can be used for sludge mixing, anaerobic digester mixing, and aerobic digester mixing. Among the advantages of the system are: minimal tank obstructions; easy cleaning, loading/unloading; ideal for varying liquid levels; simplified maintenance; easy retrofitting; and, finally, its ‘as needed operation’. Tel: 519-469-8169, Fax: 519-469-8157 E-mail: Sales@greatario.com Web: www.greatario.com Greatario Engineered Storage Systems

H2FLOW offers Pinnacle’s revolutionary Zenith ozone systems, producing up to 600 lbs/day (5% wt.) per unit. With their highly efficient design, they can be turned up/down for 100% dosage variability. They are built with solid components, are rugged, proven, extremely compact, and water cooled, with no yearly maintenance. Tel: 905-660-9775, Fax: 905-660-9744 E-mail: info@h2flow.com Web: www.h2flow.com H2Flow

Emergency gas shutoff

Water level indicator

Multiparameter meter

The Terminator Actuator emergency shutoff system sequentially closes 150 lb. cylinder valves containing toxic gas in less than three seconds, when activated from remote sensors and switches. The operator corrects the condition, checks the facility, and then manually resets the valve before restarting the gas system. Tel: 877-476-4222, Fax (949) 261-5033 E-mail: info@halogenvalve.com Web: www.halogenvalve.com

The dipper-T Water Level indicator from Heron Instruments has a yellow, flexible, high tensile steel tape jacketed with heavy duty polyethylene, in lengths up to 3,000 ft. Tape damage is prevented by a unique link between the tape and probe. In the event of the probe becoming stuck in the well the link releases the probe, preventing over stressing the tape. Tel: 800-331-2032 E-mail: info@heroninstruments.com Web: www.heroninstruments.com Heron Instruments

The YSI Professional Plus handheld multiparameter meter provides extreme flexibility for the measurement of a variety of combinations for dissolved oxygen, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, pH/ORP combination, ammonium (ammonia), nitrate, chloride and temperature. Web: www.hoskin.ca

Halogen Valve Systems

72 | September 2011

Hoskin Scientific

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The YSI ProODOTM handheld DO meter provides extreme durability for the measurement of optical, luminescent-based dissolved oxygen for any field application. Web: www.hoskin.ca

Hoskin Scientific

Sludge screen

Inclined screw press

Inline sludge screen

The RoS3Q Inclined Screw Press from Huber Technology provides high performance sludge dewatering in a compact, entirely enclosed machine. It provides efficient and reliable operation with minimal operator attendance. The slow rotational design is simple and energy-efficient. Tel: 541-929-9387, Fax: 541-929-9487 E-mail: trgregg@hhusa.net Web: www.huber-technology.com

With more than 700 installations, Huber Technology’s Strainpress® Inline Sludge Screen is designed to effectively screen sludge in pressurized lines. It reduces maintenance costs and increases the operating reliability of downstream sludge treatment systems. The Strainpress is precision manufactured of stainless steel. Tel: 541-929-9387, Fax: 541-929-9487 E-mail: trgregg@hhusa.net Web: www.huber-technology.com Huber Technology

Huber Technology

Relining pipe

The Hydro-Sludge™ Screen is an inline pressurized device that screens tramp material from sludge and dewaters the material in one operation. The enclosed system reduces odour problems, has no washwater requirements, and works on primary, secondary or combined sludges. Tel: 866-615-8130, Fax: 503-615-2906 E-mail: sales@eutek.com Web: www.hydro-international.biz

Streamliner CR relining pipe from Ideal Pipe is a strong, light corrugated HDPE pipe designed to ‘streamline’ the upgrading of old metal culverts. In-place relining with Streamliner CR eliminates the trouble and expense of road reconstruction, while improving drainage through the culvert. Tel: 800-265-7098 Web: www.idealpipe.ca

Hydro International

IDEAL Pipe

New jet aerators Based on the clogfree Flygt Npumps, the new Flygt jet aerator from ITT Water & Wastewater has become easier to install and maintain. The major changes in the new generation jet aerators are: an improved lift in, lift out structure, and a strengthened stand equipped with rubber dampers. Available with up to three ejectors, the Flygt jet aerator is a flexible aeration solution for small- and mediumsized tanks. Tel: 514-695-0100, Fax: 514-697-0602 Web: www.ittwww.ca ITT Water & Wastewater

New amalgam UV lamps

Submersible pumps

WEDECO Ozone Generators from ITT Water & Wastewater eliminate pollutants, coloured substances, odours and micro-organisms without creating harmful byproducts. They are compact in design to reduce overall footprint, and provide reduced energy consumption per unit of ozone production. Tel: 514-695-0100, Fax: 514-697-0602 Web: www.ittwww.ca

ITT’s new WEDECO ECORAY® ultraviolet lamps offer significant savings in operation and life cycle costs. The UV lamps incorporate a new long-life coating and improved overall stability and performance. An innovative gas and amalgam mixture in the lamp utilizes up to 80 percent less mercury. Corresponding electronic ballast cards have been fine-tuned to the specific requirements of ECORAY lamp aging characteristics. Tel: 514-695-0100, Fax: 514-697-0602 Web: www.ittwww.ca

KSB’s Amarex N compact maintenance-friendly submersible pumps provide optimized hydraulic system and higher efficiency which guarantee reduced energy cost. The single cast housing for motor and pump prevents leakage. Different non-clogging impellers are available to handle solids, fibres or dissolved gases for economical operation. Maximum flow rate is 53 l/s. Tel: 905-568-9200 E-mail: ksbcanada@ksbcanada.com Web: www.ksb.ca

ITT Water & Wastewater

ITT Water & Wastewater

KSB Pumps

Chemical-free water treatment

www.esemag.com

September 2011 | 73

Product & Service Showcase

Hand-held DO meter


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Automatic Duckbill sampler

Clear span buildings

This “SIMPLER SAMPLER” automates sampling, even in freezing temperatures. Inherently explosion-proof, it uses compressed air, not pumps, pushing samples up 24+m lifts/along 30+m runs. The same controller can sample multiple sites simultaneously. This versatile instrument facilitates monitoring for regulatory compliance. Tel: 1-855-873-7791, Fax: 905-873-6012 E-mail: markland@sludgecontrols.com Web: www.sludgecontrols.com

Every square foot of space is profitable in a MegaDome building. Ranging from 30’ to 125’ wide and with no limitation to its length, MegaDome provides a production or storage area built in accordance with all building codes in your area. Tel: 888-427-6647, Fax: 450-756-8389 E-mail: info@harnois.com Web: www.megadomebuildings.com

ArmorGalv is an environment-friendly process that offers superior corrosion protection and wear resistance, as well as antigalling properties. It coats and penetrates the surface of any type of steel, becoming integrated with the part. An excellent alternative for toxic coatings. E-mail: info@planthub.com Web: www.armorgalv.com

Markland Specialty Engineering

MegaDome

MJ International & Associates

P roduct & Service Showcase

Safety hatches MSU MG Safety Hatches - the open and shut case for hatch standards. With single, double and multi-door configurations in aluminum and stainless steel, they are made right here in Canada. Check us out on the web www.msumississauga.com Tel: 1-800-268-5336, Fax: 1-888-220-2213 E-mail: sales@msumississauga.com

MSU Mississauga

Safety hatches

ArmorGalv® thermal diffusion environment-friendly cost effective corrosion protection

Association for groundwater industry

MSU MG Safety Hatches set the standard in Canada for fall-through protection. They withstand pedestrian and occasional traffic loads. With single, double and multi-door configurations in aluminum and stainless steel, they are made in Canada. Tel: 1-800-268-5336, Fax: 1-888-220-2213 E-mail: sales@msumississauga.com Web: www.msumississauga.com

The National Ground Water Association is the hallmark organization for anyone affiliated with the groundwater industry. NGWA's purpose is to provide guidance to members, government representatives, and the public, for sound scientific, economic, and beneficial development, protection, and management of the world's groundwater resources. E-mail: ngwa@ngwa.org Web: www.ngwa.org

MSU Mississauga

National Ground Water Association

Metering pump

Metering pumps

Membrane bioreactor

The awardwinning delta® with optoDrive® provides diverse control and operating capabilities in a capacity range of 7.5 - 75 l/h, 362 psi - 29 psi. The delta from ProMinent has many advanced features: pulsed or continuous dosing; automatic detection of airlock, low pressure and high pressure; and an automatic degassing option. Tel: 888-709-9933, Fax: 519-836-5226 E-mail: sales@prominent.ca Web: www.prominent.ca/delta

Feature-rich and dependable Sigma series metering pumps from ProMinent help keep your chemical feed under control. Sigma pumps operate in capacities of up to 1000 LPH and pressures up to 174 psi. Microprocessor controls are easy to use, with backlit LCD for rapid and reliable adjustment.

Sanitherm has perfected containerizing their SaniBrane® MBR. The containerized SaniBrane is portable, provides excellent effluent on start-up, is operator friendly and comes pre-wired, preplumbed and tested. The system for anywhere needing reliable waste treatment with a small footprint!

Tel: 888-709-9933, Fax: 519-836-5226 E-mail: sales@prominent.ca Web: www.prominent.ca

Tel: 604-986-9168, Fax: 604-986-5377 E-mail: information@sanitherm.com Web: www.sanibrane.com

ProMinent Fluid Controls

ProMinent Fluid Controls

Sanitherm Inc.

74 | September 2011

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Water level meter

Smith & Loveless Inc. announces its latest headworks innovation, PISTA® WORKS™, a pre-engineered packaged headworks system, combining screening, grit removal and grit washing into one integrated system. It is pre-assembled and shipped direct to the job site, significantly reducing field-installation costs, while allowing for a compact footprint. All equipment components are constructed of stainless steel. Tel: 913-888-5201, Fax: 913-888-2173 E-mail: answers@smithandloveless.com Web: www.smithandloveless.com

The new Model 101 Water Level Meter with P7 Submersible Probe and extremely durable PVDF flat tape, features thick dog-bone design, reducing adherence to well casings, and increased tensile strength. It is laser marked every mm or 1/100 ft., with lengths to 1,800 m (6,000 ft). Tel: 905-873-2255, 800-661-2023 Fax: 905-873-1992, 800-516-9081 E-mail: instruments@solinst.com Web: www.solinst.com

Smith & Loveless

Solinst Canada

Specialist training Practical Hands-on Progressive Formats

With absolute precision, the new Levelogger® Edge records up to 120,000 water level and temperature data points using new linear compression sampling. It offers improved temperature compensation, reduced thermal response times, accuracy of 0.05% FS, 24 bit resolution, a 10-year battery, corrosion-resistant titanium coating, and Hastelloy pressure sensor. Tel: 905-873-2255, Fax: 905-873-1992 E-mail: instruments@solinst.com Web: www.solinst.com Solinst Canada

Trickling filters

Controlling contaminated groundwater

Tel: 905-578-9666, Fax: 905-578-6644 E-mail: contact@spillmanagement.ca Web: www.spillmanagement.ca

Waterloo Barrier is a low permeability cutoff wall for groundwater containment and control. It is a new design of steel sheet piling, featuring joints that can be sealed after the sheets have been driven into the ground, and was developed by researchers at the University of Waterloo. It has patent/patent pending status in several countries. Canadian Metal Rolling Mills assisted in developing the product. Tel: 519-856-1352, Fax: 519-856-0759 E-mail: info@waterloo-barrier.com Web: www. waterloo-barrier.com

Spill Management

Waterloo Barrier

Inline disposable filters

Mechanical actuators

Waterra currently has three Inline Disposable Filter options available: the 0.45 Micron high turbidity FHT-45, the 0.45 Micron medium turbidity FMT-45, and the 0.2 Micron CAP300X2. All our filters use high quality polyethersulphone filter media (which offers excellent particle retention above the target micron size range) and are pre-rinsed with 1L of de-ionized water to ensure purity. Tel: 905-238-5242, Fax: 905-238-5704 E-mail: sales@waterra.com Web: www.waterra.com Waterra

The portable, electrically operated Hydrolift has been one of the most popular mechanical actuators for the Waterra Inertial Pump, and we've been working to make it better. Today, the improved Hydrolift is more durable and easier to use and, most importantly, more affordable than ever. Tel: 905-238-5242, Fax: 905-238-5704 E-mail: sales@waterra.com Web: www.waterra.com Waterra

www.esemag.com

Water level data logger

Waterloo Biofilters® are efficient, modular trickling filters for residential and communal sewage wastewaters, and landfill leachate. Patented, lightweight, synthetic filter media optimize physical properties for microbial attachment and water retention. The self-contained modular design for communal use is now available in 20,000L/d and 40,000L/d ISO shipping container units - ready to plug in on-site. Tel: 519-856-0757, Fax: 519-856-0759 E-mail: wbs@waterloo-biofilter.com Web: www.waterloo-biofilter.com Waterloo Biofilter

Containment system Westeel's CRing Containment Systems are ideal for petrochemical, frac water storage, oil and gas, fertilizer, hazardous material, and agricultural applications. All systems are made with high-strength (50-ksi) steel and have heavy-duty G115 galvanizing, meeting the stringent requirements of ISO 9001. Tel: 1-888-674-8265, 204-233-7133 Fax: 1-888-463-6012 E-mail: info@westeel.com Web: www.westeel.com Westeel

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Headworks system


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 WFP campaign offers a chance to win a trip

Acoustic Panels, Enclosures & Products WE WELCOME YOUR INQUIRIES

Email: info@acousticproductsales.com Web: www.acousticproductsales.com Tel: (613) 551-6100

Water For People (WFP) has launched a Crowdrise.com campaign to raise $2 million. Instead of just donating their money, a generous group of Water For People donors are leveraging their $1 million pledge by also challenging supporters to raise another $1 million. The two-month “Donate to Drink,” campaign, which will run through October 31, 2011, began with a $150,000 donation from CH2M HILL, a long-time supporter of WFP. Those who create fundraising pages on www.crowdrise.com/donatetodrink and collect $1,000 in donations will be entered in a draw for a trip for two to join a WFP volunteer expedition in Rwanda. www.waterforpeople.org

Unprecedented response to WERF research program The Water Environment Research Foundation (WERF) received an unprecedented number of pre-proposals seeking Polymaster™ System Now CSA Listed

• ANTHRACITE • QUALITY FILTER SAND &GRAVEL • CARBON • GARNET ILMENITE • REMOVAL & INSTALLATION 20 Sharp Road, Brantford, Ontario N3T 5L8 • Tel: (519) 751-1080 • Fax: (519) 751-0617 E-mail: swildey@anthrafilter.net • Web: www.anthrafilter.net

High Pressure Water Jetting Liquid/Dry Vacuum Services Dry Ice Cleaning Hydro Vac Excavating

Markham, Ontario

The POLYMASTER™ liquid polymer mixing/diluting system complies with both UL778 and CSA C22.2 No. 108-01 standards. The system thoroughly activates emulsion, dispersion and solution polymers, including new high molecular weight liquid polymers, and can produce dilute solution (0.1% – 2.0%) at rates up to 50 gpm. The patented “Gatlin” is a motorized mixing chamber that segments the polymer into ultra-thin film for maximum activation. This system is unique in that the degree of activation is not affected by fluctuating water pressures.

905-747-8506

See us at WEFTEC booth 2719

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WeKnowWater@BV.com Consulting • Engineering • Construction • Operation

76 | September 2011

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Neptune Chemical Pump Co. North Wales, PA Tel: 888-3NEPTUNE or 215-699-8700 E-Mail: info@neptune1.com www.neptune1.com

Environmental Science & Engineering Magazine


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 funding for stormwater management research under its 2011 Unsolicited Research Program. WERF Director of Research, Dan Woltering points out, however, that while stormwater management may be a hot issue, utilities continue to face new challenges on many fronts. These include wastewater operations, energy, asset management, nutrient removal and recovery, and the effects of trace organic compounds. He also noted an increase in the amount of leverage, or in-kind funding, offered in the pre-proposals. www.werf.org

Canada and Alberta join in WWTP public-private partnership The Government of Canada will contribute up to $9.95 million through the P3 Canada Fund towards the Evan-Thomas Water and Wastewater Treatment Facility project in Kananaskis County, Alberta. Alberta’s innovative P3 procurement approaches for delivering schools and roads have proven successful. Now, in cooperation with PPP Canada, a P3 template is being established for water and wastewater infrastructure projects. Once selected, the private sector partner will design, construct and provide partial financing for the Evan-Thomas facility project. The partner will also be responsible for operations and maintenance of the new water treatment plant, the new wastewater treatment plant, and the water storage and distribution systems, for 10 years after construction is completed. Ownership of the facility will rest with the Alberta government.

BC approves Vancouverʼs solid waste management plan

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The British Columbia government has approved a solid waste management plan for Metro Vancouver that minimizes garbage generation, maximizes recycling, and includes the addition of several conditions to ensure the environment is protected. The plan includes: • New goals for diverting 70 per cent of the region’s waste through recycling, continued overleaf...

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composting and other programs by 2015. • Strategies for reducing the amount of waste produced by 10 per cent by 2020. • A range of options to deal with the greatly reduced waste stream, that this plan will produce. The ministry thoroughly reviews any solid waste management plan, to ensure it meets all rules for waste management. This includes a requirement for reduction and recycling, before land filling or waste-to-energy options are considered. Local governments are required to consult the public, and First Nations, before submitting their plan. www.gov.bc.ca

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Charlottetownʼs water and sewer systems to be improved The Prince Edward Island government is committed to working with the City of Charlottetown and the federal government to ensure that improvements are made to water and sewer systems, Last year, the City commissioned a study on separating the combined system, with the understanding that the province supported the project. “The province has been on-side with this for quite some time,” said Environment, Energy and Forestry Minister, Richard Brown. “Now that the City agrees that improvements are a priority, we can present a unified case to the federal government, and get the work underway as soon as possible.” Once funding is finalized, current estimates suggest that the project will take roughly three years. Combined storm systems are no longer being built in Canada. In February 2009, the Canadian Council of Ministers of the Environment endorsed a national strategy and a call for stricter regulations for wastewater management, to protect human health and the environment.

Ontario Government releases annual drinking water report The Ontario government’s Annual Report on Drinking Water 2011 highlights key achievements and successes in protecting drinking water. 78 | September 2011

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 The province is making progress in cleaning up its Great Lakes. Lake Erie's Wheatley Harbour was removed as an Area of Concern and Lake Superior's Jackfish Bay was changed from an Area of Concern to an Area in Recovery. The health of Lake Simcoe is improving. The goal of the Lake Simcoe Protection Plan's phosphorus reduction strategy is to reduce phosphorus from 72 to 44 tonnes per year. According to the report, the new Water Opportunities and Water Conservation Act is helping Ontario develop innovative water technologies which create jobs. In 2011, Ontario provided $7 million for landowners to take action to protect their drinking water sources through the Ontario Drinking Water Stewardship Program. The Chief Drinking Water Inspector's Annual Report 2009-2010 shows 99.88 per cent of drinking water tests, reported by municipal residential drinking water systems, met Ontario's drinking water quality standards.

Explosion at Toronto WWTP A minor explosion occurred at the Ashbridges Bay wastewater treatment plant on September 17. Toronto Water confirmed that a fire started at the pelletizer facility at the treatment plant at about 8:45 a.m. The pelletizer is operated by Veolia Water Canada Inc. on behalf of the city, turning biosolids into pellets that the company sells as fertilizer. Veolia Water released a statement that confirmed the incident, saying there were no injuries or environmental damage, and the proper officials had been notified. According to Toronto Fire, a pellet-drying machine suffered extensive damage in the incident. The Ontario Fire Marshal has been called in to investigate the explosion. In 2003, a five-alarm fire gutted a pelletmaking facility at the plant.

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Oil Sands project to recycle up to 97% of facilityʼs water Grizzly Oil Sands ULC has selected GE’s produced water evaporation technology for its Algar Lake project near Fort McMurray, Alberta. Phase 1 of the Algar Lake Steam-Assisted Gravity Drainage continued overleaf... www.esemag.com

WƌŽǀŝĚŝŶŐĞŶŐŝŶĞĞƌŝŶŐĂŶĚƐĐŝĞŶĐĞͲďĂƐĞĚƐŽůƵƟŽŶƐ DĞĞƟŶŐƚŚĞŶĞĞĚƐŽĨŽƵƌĐůŝĞŶƚƐ ϭͲϴϬϬͲϮϲϱͲϵϲϲϮ ǁǁǁ͘ƌũďƵƌŶƐŝĚĞ͘ĐŽŵ September 2011 | 79


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 (SAGD) project will produce 5,000-6,000 barrels per day of bitumen. By using GE’s process, it will recycle up to 97 percent of the produced water. GE also is also providing the Algar Lake SAGD project with system design, equipment, instruments and controls, training and site support. GE will deliver equipment to the site in the first half of 2012, with installation and commissioning scheduled for the second half of 2012. Partnering to provide sustainable solutions

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ITT completes acquisition of YSI ITT Corporation has completed its acquisition of YSI Incorporated, forming a water-focused analytics business with annual revenues of approximately $300 million. YSI, which was founded in 1948, is a developer and manufacturer of sensors, instruments, software, and data collection platforms for environmental water monitoring. Gretchen McClain, president of ITT's Fluid and Motion Control business, will become chief executive officer of Xylem, the new stand-alone water company, which is separating in a spinoff from ITT later this year. www.itt.com

Quebec takes major step in meeting Great Lakes agreement

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80 | September 2011

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Québec’s government has announced two draft regulations that will help it to meet its commitments under the Great Lakes— St. Lawrence River Basin Sustainable Water Resources Agreement. The first regulation deals with the authorization framework for projects entailing the transfer of water from the St. Lawrence River basin. The second regulation amends water withdrawal declaration rules. The Agreement exists to foster sustainability by ensuring that water withdrawals are managed by taking into account their cumulative impact and by establishing a strict framework for granting limited exceptions to the prohibition on transferring water out of the basin. Quebec’s Water Act, adopted in June 2009, confirms the legal status of water

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 resources and stipulates the responsibilities of the government as guardian of the resource on behalf of the population. www.mddep.gouv.qc.ca

The entire Florida Keys is in the process of upgrading local wastewater treatment plants, and these measures should eliminate this bacterium source.

Human pathogen killing Florida Key coral

Peter Laughton honoured by WEAO

A research team from Rollins College in Florida and the University of Georgia has identified human sewage as the source of the coral-killing pathogen that causes white pox disease of Caribbean elkhorn coral. The team has known since 2002 that the bacterium that killed coral was the same species as found in humans, Serratia marcescens. In order to determine a source for the pathogen, the research team collected and analyzed human samples from the wastewater treatment facility in Key West and samples from several other animals, such as Key deer and seagulls. While Serratia marcescens was found in these other animals, genetic analyses showed that only the strain from human sewage matched the strain found in white pox diseased corals on the reef. The final piece of the investigative puzzle was to show that this unique strain was pathogenic to corals. With funding from Florida’s Mote Marine Laboratory “Protect Our Reefs” grant program, the team conducted challenge experiments by inoculating fragments of coral with the strain found in both humans and corals to see if it would cause disease. The strain caused disease in elkhorn coral in five days. This research reveals a new disease pathway, from humans to wildlife, which is the opposite of the traditional wildlifeto-human disease transmission model. Movement of pathogens from wildlife to humans is well documented—for example, bird flu or HIV—but the movement of disease-causing microbes from humans to marine invertebrates has never been shown before. www.esemag.com

Long time Environmental Science & Engineering Editorial Advisory Board Member, Peter J. Laughton, P.Eng., was recently awarded the 2011 Geoffrey T.G. Scott Memorial Award, by the Water Environment Association of Ontario at its annual conference in Toronto. For over four decades, Mr. Laughton has been widely known for his contributions as a consultant to the water environment industry in Canada and abroad, with R.V. Anderson Associates Limited, and more recently as a sole practitioner. He is also admired for his contributions as a volunteer for professional organizations, serving on the board and as an officer for the Water Environment Association of Ontario, the Canadian Association on Water Quality, the President’s Executive Committee of the Water Environment Federation, and on the Governing Board of the International Water Association. But it is for his volunteer leadership in championing university level education in the water environment industry in Canada and abroad, that he was nominated for this award, by Tom Davey, Founding Editor of ES&E Magazine.

As a graduate of the University of Toronto, Mr. Laughton went back as a guest lecturer year after year, starting in the 1970s, to teach both undergraduate and graduate students the practical applications of their environmental engineering studies, based on his experiences as a consulting engineer.

Peter Laughton (right) with ES&E publisher Steve Davey at a recent 5S meeting.

Mr. Laughton did not limit his commitment to university education to the University of Toronto alone. He was also a guest lecturer at McMaster University in Hamilton, Ontario, and more recently at the University of Montreal in Quebec. He was a graduate of Ryerson, where he also served for many years as a volunteer continued overleaf...

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Advertiser INDEX

Company

Page



ABS Pumps ......................................3 ACG Technology............................83 Altech Technology Systems ...Insert American Public University ..........31 American Water .............................61 Associated Engineering..................5 Avensys Solutions.........................36 Bürkert Fluid Control.....................37 Canadian Safety .............................11 Cancoppas .....................................67 Cole Engineering ...........................52 Corrugated Steel Pipe Institute ....84 D’Aqua Technologies ....................59 Degremont Technologies..............27 Delcan Water ..................................16 Denso .............................................53

in various capacities, starting in 1984 at the Faculty of Engineering and Applied Science, on the Civil Engineering Advisory Committee. The school honoured him with a Doctor of Engineering – Honoris Causa in 1997. As a result of his efforts and leadership, Peter J. Laughton has inspired countless students and engineers to make their careers in the water environment industry. According to Gail Scott, who presented the award, “Peter Laughton is a true champion of advancing the mission of the water environment industry and a worthwhile candidate for the Geoffrey T.G. Scott Memorial Award.”

Echelon Environmental.................13 Endress + Hauser ..........................19 Eramosa Engineering....................61 Globe...............................................62 Gorman-Rupp.................................17

Nanomaterials provide boost to biosolids dewaterability and odor reduction

Government of Bermuda...............46 Greatario.........................................10 Greyline Instruments.....................60 H2Flow ............................................48 Heron Instruments.........................30 Hoskin Scientific................12, 22, 45 Huber Technology ...........................9 Hydro International........................53 Ideal Pipe ........................................49 ITT Water & Wastewater ..................7 John Meunier .................................26 JWC Environmental.......................43 Kinecor LP......................................69 KSB Pumps ....................................38 Levelton Consultants ....................55 Markland Specialty Engineering ..57 MegaDome......................................59 MSU Mississauga ..........................25 Myron L Company .........................65 National Ground Water Assoc. .....23 Neptune Chemical Pump ..............76 Orival...............................................39 Pro Aqua ...................................29, 63 ProMinent .........................................2 Robillard Document Mgmt. ...........48 Sanitherm Inc. ................................57 SEW-Eurodrive...............................11 Smith & Loveless...........................44 Solinst Canada...............................35 SPD Sales .......................................58 Stantec............................................36 StormTrap.................................32, 33 Waterloo Biofilter Systems ...........60 Waterra Pumps ........................21, 51 Whipps............................................54 WTP Equipment .............................34 XCG Consultants ...........................23

Could nanoscale additives be the next big thing in biosolids management? Findings from a recently completed Water Environment Research Foundation project, investigating the use of nanomaterials to address biosolids odors and dewaterability, suggest that these tiny particles hold tremendous potential for wastewater treatment. Despite being no more than 100 nanometers (nm) in any one dimension, nanomaterials have proportionately high surface areas. At nanoscale many materials are far more reactive than their conventional-sized counterparts, often interacting with the surrounding medium in ways not possible with larger particles. Because of their unique properties, nanomaterials have recently replaced dissolved, micron-sized forms in several industrial and commercial products, and many hold promise for improving dewatering and reducing odors in biosolids processing operations. The project conducted preliminary experiments on nearly a dozen different nanomaterials as additives to determine their ability to improve dewatering and reduce odor production in the cake. Samples of biosolids were dewatered in the laboratory, and the resulting cake samples were stored for odorant analyses. The major odor-causing gases studied were the volatile organic sulfur compounds (VOSCs), mainly methyl mercaptan and dimethyl sulfide.

Researchers then studied nanomaterial characteristics for the factors which impact dewatering and odor production. In general, the nanomaterial additives reduced the optimum polymer dose and increased the amount of resulting cake solids. Researchers also observed substantial reduction in the production of VOSCs. Following their initial analysis, the team then performed detailed dewatering and odor production studies using three additives selected from the screening tests. The dewatering studies focused on the effect of polymer type on dewatering using the nanoadditives. Polymers of high, medium, and low charge-density were used with the nanoadditives for dewatering return activated sludge and digested sludge from two Pennsylvania utilities. Depending upon the source of sludge, the researchers observed between 20 to 60 percent reduction in optimal polymer dose, with a 10 to 20 percent increase in cake solids. Odor reduction proved just as successful. Researchers observed 30 to 70 percent reduction in the production of VOSCs. Moreover, the nanoparticles that led to the reduction of odorant production did not inhibit generation of methanogenic bacteria. This interesting outcome is highly desirable because methanogenic bacteria help to deodorize cake during storage, and research has shown that odors are worse when methanogens are inhibited. In addition to these benefits, additional work associated with the WERF project Wastewater Treatment Plant Design and Operations Modifications to Improve Management of Biosolids Odors and Sudden Increases in Indicator Organisms (SRSK4T08) has shown that one of the nanoadditives was able to inhibit regrowth of indicator bacteria after dewatering. This is important for utilities that are experiencing regrowth issues in their cake, which can lead to exceedance of regulatory requirements for fecal coliforms. Although the researchers observed a strong correlation between the characteristics of the sludge and those of the nanoscale additives, further studies are required to better understand the mechanisms involved during nanoadditiveaided dewatering.

Environmental Science & Engineering Magazine


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Environmental Science & Engineering Magazine September-October 2011  

This issue focuses on: New combined sewer overflow treatment technology; New drinking water source for Abbotsford; improving the energy effi...

Environmental Science & Engineering Magazine September-October 2011  

This issue focuses on: New combined sewer overflow treatment technology; New drinking water source for Abbotsford; improving the energy effi...