RECOMMENDATION PREVIOUS REPORTS PERTINENT TO THIS MATTER BACKGROUND

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1 1 ma Agenda Item # Page # TO: FROM: SUBJECT CHAIR AND MEMBERS ENVIRONMENT AND TRANSPORTATION COMMllTEE MEETING ON MARCH 20,2006 PETER W. STEBLIN, P.Eng. GENERAL MANAGER OF ENVIRONMENTAL AND ENGINEERING SERVICES AND CITY ENGINEER POLLUTION CONTROL PLANT (PCP) DISCHARGE STRATEGY FlNAl RFDnRT FSk3An RECOMMENDATION I1 That, on the recommendation of the General Manager of Environmental and Engineering Services and City Engineer, the Pollution Control Plant (PCP) Discharge Strategy, SNC-Lavalln Engineers and Constructors Inc. and Associates Limited, March 2006 BE ADOPTED by Municipal Council as the basis for establishing effluent criteria for future expansion and upgrades of Pollution Control Plants in London. PREVIOUS REPORTS PERTINENT TO THIS MATTER ETC -January 30, 2006 Southside Pollution Control Plant Update (2006) ETC - November 29, 1999 Southside PCP EA Request for Contract Extension ETC -August 26, 1996 Appointment of Consulting Engineers Class Environmental Assessment for New Southside Pollution Control Plant and Sludge Management Feasibility Study Purpose: BACKGROUND The PCP Discharge Strategy is complete and following acceptance of the report by Municipal Council, the strategy will be used as a valuable background document for the completion of future pollution control plant expansions in the City of London. Background: Report Basis and Ontario Ministry of Environment Acceptance: The basis for the development of the Discharge Strategy was to comply with a Condition from the Minister of Environment in response to the Bump-Up Requests on the Southside PCP EA. In the letter dated, January 16, 2002, Minister of the Environment, Elizabeth Witmer, MPP stated that An individual environmental assessment (EA) is not required, on the following conditions: $ 1. The Corporation of the City of London complete the work outlined in the Environmental Permitting and Approval Proposed Work Plan, Mar. 2000, SNC-Lavalin Engineers & Constructors IncorporatedR. V. Anderson Associates Limited and approved City of London Council Apr. 3, The Corporation of the City of London make copies of the studies prepared under this work plan available to each of the seven bumpup requesters, and inform the Director, Environmental Assessment and Approvals Branch, Ministry of the Environment (MOE), by letter when this has been done; and %

2 2 Agenda Item# Elm Pa e# The Director, Environmental Assessment and Approvals Branch, MOE be in receipt of the letter noted in Item 2 above, thirty days before granting any permits or approvals related to this undertaking under the Ontario Water Resources Act. In the recent Ministry of Environment letter of January 27, 2006, documenting the review of the December 2005 Draft Final PCP Discharge Strategy, the Ministry states that: The Region considers that this report meets one of the conditions b.e., Condition I] imposed by the Minister of the Environment related to the Southside PCP. The other Condition requiring distribution of the copies of the Reports in the Environmental Permitting and Approval Proposed Work Plan was completed in May 2002 when copies of the report were distributed following the Minister of Environment s decision. Scope of Study: The Discharge Strategy examines the quality of the Thames River from samples taken from long-term monitoring locations and from new locations upstream and downstream of the discharge outfalls from the city s Pollution Control Plants. River samples were collected, analysed and compared with the long-term record. Benthic samples were collected and compared with long term data and new methods of analysis were undertaken in response to Ministry of Environment comments. Estimated expansion dates and flows for future expansions were adopted from the Sanitary Servicing Plan Update (2003). Flow data was used to establish future effluent limits based on existing conditions, current PCP treatment performance and future concentration and contaminant loading. Public and Agency Consultation: The City of London followed the Master Plan process identified in the Municipal Class Environmental Assessment document (Municipal Engineers Association, 2000). The Ontario Ministry of Environment and Environment Canada were consulted early in the process and were provided with the study work plan prepared by SNC-Lavalin Engineers and Constructors Inc. As the project progressed, additional input was sought and further analysis and interpretation were completed based on comments from Environment Canada and the Ontario Ministry of Environment. Extensive Public Consultation was undertaken beginning with the establishment of a comprehensive mailing list based on the Environmental Assessment work connected with the Southside Pollution Control Plant. Relevant government agencies were notified of study commencement and three public, information centres were advertised and held. The notice of completion was published in December 2005 and copies of the report were available for public review at City Hall and the Central and Lambeth Branches of the London Public Library. The mandatory 30-day public review period expired on January 27, The Ministry of Environment provided comments on the December 2005 Draft Final Report. All comments have been incorporated in the March 2006 Final Report. Discussion: The PCP Discharge Strategy sets future phosphorus effluent concentrations in mg/l and loading to the river in kgld to levels that will ensure sustainable growth in the City while minimizing the impact on the river. Phosphorus levels are of concern because the background levels in the Thames River are already higher than the Interim Provincial Water Quality Objective of 0.03 mgll. Phosphorus levels upstream of London are about 0.14 mgll or about four times the PWQO and there is an increase in levels at sampling stations downstream of London at 0.20 mgll. Phosphorus is a nutrient essential for plant and animal life. Sources of phosphorus include human and animal waste, detergents, and fertilizers which can enter the river from treated effluent and from run-off from urban and agricultural areas. The contribution of the PCP effluent to the total phosphorus load is about 17% of the annual load to the river (5 year average

3 3 Agenda Mrn Item # Page # between 1999 and 2003). The City of London can reduce the load from the PCPs by optimizing operations and changing treatment processes. Benthic sampling and analysis has been used by the City of London for many years to monitor the effect of pollution in the Thames River. By examining the type and number of macro invertebrates in the benthos layer, the relative health of the river can be assessed. Comparison of 2004 results with yearly and long-term data determined that there was no evidence of severe or consistent degradation in water quality downstream of the PCPs. The work also found that the conditions at the present time appear to have improved compared to those observed in! About 90% of the phosphorus in wastewater is currently removed at the City s PCPs by secondary treatment methods using biological and chemical processes. Optimization of plant performance and an increase in the use of chemical coagulants will increase the quantity of phosphorus removed and reduce the concentration of phosphorus in the effluent. Accordingly, the preferred solution recommends reductions in the Certificate of Approval limits and objective loads at Pollution Control Plants over the next 20 years. The stricter limits will systematically be imposed on each plant and be incorporated into their Certificates of Approval as each plant is expanded in the future. More stringent limits are also proposed for the Greenway Pollution Control Centre even though an expansion is not currently contemplated and the Certificate of Approval is not in need of amendment. Expansion and upgrades to the Vauxhall PCP are dependent on potential growth in the sewershed. Because the City is already doing an EA to deal with combined sewer overflows, a minor expansion of 0.5 MlGD is also being undertaken as recommended in the Sanitary Servicing Plan Update (2003). The expansion will be funded through Development Charges. The actual timing for the expansion will depend on growth in the Vauxhall sewer shed. The proposed compliance and objective limits for effluent criteria are based on a monthly average of the test results. Compliance limits refer to the maximum (or in some cases minimum) value for the given test parameter. When a test result is out of compliance, the Ontario Ministry of Environment is notified, the reason for non-compliance is investigated and corrective action is undertaken. Objective limits are stricter target criteria that Pollution Control Operations is attempting to meet through continuous improvement and optimization. Effluent criteria are finalized in Certificates of Approval issued by the Director of the Environmental Assessment and Approvals Branch of the MOE after the Class Environmental Assessment and detailed design for the PCP Expansion and Upgrade is completed. Conclusion: In summary, the City is committed to reduce phosphorus loads so that the net effect after adding the future Southside PCP will be an overall reduction in the total phosphorus discharge. The net reduction is achieved by imposing stricter limits at the other City PCPs. An Executive Summary from the Pollution Control Plant Discharge Strategy (March 2006) explains the strategy in more detail. The reduction is shown in Figure ES-1 of the Executive Summary where, despite population growth in the City over the next 20 years, the total phosphorus load to the Thames River is reduced. I

4 4 Agenda Item # Page Elm?$ Acknowledgements: This report was prepared within the Wastewater and Drainage Engineering Division by Richard Todd, P.Eng., Environmental Services Engineer, and Tom Copeland, P.Eng., Division Man age r. SUBMITTED B RON STANDISH, P.Eng. DIRECTOR, WASTEWATER AND TREATMENT /om RECQMMENDED BY: - PETER W. STEBLIN, P.Eng. GENERAL MANAGER OF ENVIRONMENTAL AND ENGINEERING SERVICES AND CITY ENGINEER.I RJT/pt Attach: Appendix A - Executive Summary PCP Discharge Strategy, March 2006, SNC-Lavalin Engineers and Constructors. C.C. Mart Lupp, SNC-Lavalin Engineers and Constructors Inc. Robert Kuzyk, Associates Limited Y:\Shared\Wastew\WPDOCS\RPRT-ETC~C - Finallzafion of PCP Discharge Sfrategy.doc

5 mn APPENDIX A Agenda item # Pa e# Final Clty of London Pollutlon Control Plant (PCP) Dlachame Strategy March 2006 EXECUTIVE SUMMARY The Pollution Control Plant (PCP) Discharge Strategy provides a City-wide strategy to manage treated effluent discharges to the Thames River from the City of London s plants. The study looks at the impact of the discharges on the river at locations upstream and downstream of the City and each PCP discharge point. The intention of the strategy is to set future phosphorus effluent concentrations and loads to levels that will ensure sustainable growth to the City while minimizing the impact on the river. Phosphorus is a necessary nutrient for plant and animal life. Phosphorus is commonly found in the aquatic environment in the form of inorganic phosphates and organically bound phosphorus, in both the dissolved and particulate forms. While phosphorus is an essential nutrient for the growth of organisms, elevated concentrations of this element in surface waters can lead to excessive plant growth and nuisance algal concentrations. The Ministry of the Environment (MOE) has established an interim Provincial Water Quality Objective (PWQO) of 0.03 mg/l to protect against excessive plant growth in rivers and streams. Sources of phosphorus to the Thames River in the vicinity of the City are numerous and include: agricultural run-off and groundwater flow from feedlots, pastures, fertilized fields, septic systems, etc. urban stormwater drainage including combined sewer overflows, and runoff containing street drainage, waste from resident bird and animal populations, residential fertilizers, etc., and Pollution Control Plant (PCP) effluent discharges. Human waste, food residues and domestic cleaning products associated with household (sanitary) wastewater are the major contributors of total phosphorus (TP) to the City s PCPs, exceeding the contribution from commerciallindustrial sources to the City treatment plants. As the population of the City of London grows, so grows the demand on the City s PCPs to control TP discharges to the Thames River. Between the periods to , the average annual sewage flows to the City PCPs increased by approximately 15% in response to increases in population and City growth. Despite this increase in sewage flows, the actual TP loading to the river from the PCPs declined by approximately 11% over this same time interval. This can be attributed to the improved treatment at the City PCPs (Le,, reduced TP discharge concentrations over time). On average approximately 90% of the TP is currently removed from the raw sewage by the City PCPs. This reduction demonstrates excellent performance for the conventional activated sludge and extended aeration treatment systems used at the City PCPs. SNC*LAVALIN +) Engineers &constructors Page ES-I Assoclstes Llmlted

6 Agenda Item # Pa Elm e# City of London Pollution Control Plant (PCP) Discharge Strategy Final A mass balance of TP sources in the City of London was used to estimate current conditions using data for the 5-year period The mass balance indicates that on an annual average basis the City PCPs contribute about 17% of the total phosphorus loading measured in the river downstream of the City at Byron. "Other" sources in the City which primarily include tributary loads and stormwater runoff represent approximately 14% of the TP load in the river at Byron. The vast majority (approx. 68%) of the TP in the river originates upstream of the City (30% from the South Branch as measured at Whites Bridge, and 38% from the North Branch as measured at Clarke Road). A review of the City's historical water quality monitoring record at Byron indicates that TP concentrations in the Thames River downstream of the City have not increased (and may have actually decreased) since 1978 (when data was first routinely collected and the population was approx 254,000). This shows that after an 100,000 (approx.) population increase, the concentrations have remained the same or have reduced. The excellent TP removal at the City PCPs and other nutrient reduction initiatives completed by the City (e.g., sewer separation and stormwater management projects, sewer use bylaw enforcement, etc.), plus participation /funding of other programs upstream of the City, have all contributed to this situation. Benthic macro-invertebrate surveys completed for this study found the overall effect of the PCPs on water quality based on the benthic community results to be low to moderate, and localized within the City environment. Water quality in the Thames River within and downstream of the City appears to be consistently better in 2004 compared with conditions found in historical surveys in Fish habitat conditions in the river have also been noted to be improving over the last several years. Total phosphorus concentrations exceed the interim PWQO concentration of 0.03 mgll in both the North and South branches of the Thames River as they enter the City, as well as within the City itself. Since the TP concentrations exceed the PWQO, the Thames River, like many watercourses in Southern Ontario, is classified by the MOE as a "Policy 2" watercourse with respect to TP. As a "Policy 2" watercourse, no further degradation in water quality is permitted and all practical measures should be taken to upgrade the water quality to the Objective. Over the next 20 years the population of the City of London is projected to increase by approximately 20%. This growth will place an additional TP loading burden on the river via the City PCPs. Each City PCP currently treats sewage in accordance with its Certificate of Approval (C of A) issued by the MOE under the Ontario Water Resources Act. The PCPspecific Cs of A typically define objective and legal maximum limits for TP concentrations and loads in the PCP effluent discharges to the river. In light of the "Policy 2 designation, the MOE has indicated that for any future PCP upgradeslexpansions, the existing TP treatment limits +) Engheers SNC*LAVALIN &Constructors Page ES-2 Associates Limited

7 Agenda Item # BI City of London Pollution Control Plant (PCP) Discharge Strategy Final March 2006 defined in the Cs of A should be re-examined on a City-wide basis. This has led to the development of this City of London PCP discharge strategy. The goal is to ensure a net drop in the phosphorus load to the river while the population grows by improving phosphorus treatment at the PCPs. The TP discharge strategy is based on a 20-year design horizon. The required increases in rated capacity of the City PCPs to support City growth over this period have been extracted from the separate Cify of London Sanitary Sewerage Servicing Plan Update (Earth Tech, December 2004). The Cs of A which govern the operation of each City PCP provide a suitable framework for developing effluent concentration and loading targets against which TP reductions over time can be measured and compliance determined. Cs of A are legally enforceable control documents. Consistent with the "Policy 2" designation for the river, it is the City's intention to offset any additional TP loading to the river attributable to future City growth (Le., future PCP expansions) with an equal or greater TP load reduction within the City. This would be accomplished by systematically reducing the TP objectives and TP non-compliance limits defined in the PCP Cs of A over the 20-year design horizon. By focussing on the PCPs themselves (as opposed to other point or non-point sources) any trade-offs between sources would be "kind-for-kind'' and would remain readily measurable, verifiable and within the control of the City. Specifically, the proposed PCP discharge strategy assumes: the proposed PCP expansions would proceed according to the City of London Sanifary Sewerage Sewicing Study (2004 update) schedule as follows: Greenway PCC would continue to operate as a 33.5 MlGD facility; Oxford PCP would be expanded from 2.2 to 4.2 MlGD in 2007; Vauxhall PCP would be expanded from 4.6 to 5.1 MlGD in 2008; Adelaide PCP would be expanded from 8 to 10 MlGD in 2009; Southside PCP would be built and operated as a 4 MlGD plant by 2016 and possibly earlier; Pottersburg PCP would be expanded from 8.6 to 10.6 MlGD in 2019; Southland PCP would remain operational for the foreseeable future but would cease operations once the Southside PCP is operational or connectlon to the proposed Wonderland Pumping Station is undertaken; Westminster PCP would remain off-line. SNC.l.hVALlN +) Engheen 81 Constructors Page ES-3 Associates Limited

8 mq Agenda Item # Pa e# City of London Pollution Control Plant (PCP) Dlscharge Strategy Flnal March 2006 stricter TP discharge limits would systematically be imposed on each plant and incorporated into their Cs of A as each plant is expanded in the future, in order to achieve a decrease in overall City TP limit and TP objective loads over time, new, more stringent TP discharge limits would be imposed on the Greenway PCC despite the fact this plant is not slated for expansion in the next 20 years, by 2019 before the end of the 20-year design horizon, the Greenway PCC would be operating under a C of ATP discharge limit of 0.65 mgll (with a 0.55 mgll objective), while all other City PCPs would be operating at limits between 0.65 to 0.75 mg/l limit (with 0.5 to 0.6 mgll objectives), and; it is proposed that for plants currently regulated under "total ammonia" that this be replaced with "un-ionized ammonia" limits of 0.1 mg/l for compliance and 0.08 mg/l for objective concentrations to be consistent with the majority of City PCPs. Based on the above, over the next 20 years, the cumulative city-wide C of A-defined PCP TP load limit (i.e., the total TP load discharged from all city PCPs assuming each PCP is discharging at its maximum allowable legal limit) would decrease from 221 to 206 kg/day. This 15 kg/day reduction is a significant decrease when compared to the 38 kglday increase which would occur under a "do nothing" scenario where the PCPs are allowed to expand with no reduction in their respective C of A TP limits. Over the same 20-year period, the corresponding cumulative city-wide C of A-defined TP objective load (Le., the total TP load discharged from all city PCPs assuming each PCP is discharging at its treatment objective limit) would decrease from 176 to 168 kglday. In the PCP discharge strategy no attempt has been made to realize any TP credits associated with other City initiatives such as combined sewer separations, stormwater management projects or City participation in, and/or funding of, programs sponsored by the Upper Thames River Conservation Authority. It has been assumed however, that these other City initiatives to reduce TP loadings to the Thames River would continue and would lead to further improvement to the river environment. SNC.LAVALIN +) Engineers & Constructors Page ES-4 Associates Limited

9 Agenda Item # Pa e# Clty of London Pollution Control Plant (PCP) Discharge Strategy Final March 2006 Figure ES.1 illustrates the proposed decrease in the TP C of A limit and objective loads summed across all City PCPs over the next 20 years. Figure ES.l also includes a plot of the growth in population over time. As shown, the population is expected to grow by approximately 70,000. The increase in population and industrial, commercial and institutional growth is offset by a reduction in the phosphorus loading over the 20 year study period Figure ES.1: PCP Total Phosphorus Load Reductions Versus Population Growth $'.E F e Year ---c C of A Non-cowliance Load - c C of A Objective Load -L- Pop'n Rojeclions (Tnousands) The development of the City of London Pollution Control Plant (PCP) Discharge Strategy has been conducted following procedures consistent with the Master Planning Process as outlined in the Municipal Engineers Association's Class Environmental Assessment (Class EA) document, dated June The PCP Discharge Strategy will ultimately be integrated with other related City initiatives, which include the updated City of London Sanitary Sewerage Servicing Study. SNC+LAVAUN +j) Engineers & Constructors Page ES-5 Assoclates Limlted