June 29, 1999

To:Works Committee

From:Commissioner of Works and Emergency Services

Subject:Class Environmental Assessment for Residue Management Facilities Project

R.C. Harris Filtration Plant (Ward No. 26)

Purpose:

The purpose of this report is to provide information on the progress to date of the Class Environmental Assessment for Residue Management Facilities Project at the R.C. Harris Filtration Plant.

Funding Sources, Financial Implications and Impact Statement:

Funding for approximately $19 million has been provided for this project in the 1999-2003 Capital Works Program based on a preliminary estimate, of which $558,000.00 has been allocated to the pre-design study incorporating the Class Environmental Assessment. To date, a funding authority of $1,850,000.00 has been obtained. Authority for additional expenditures will be requested in future to carry out the pre-design, design and construction for this project. Since the revised estimated cost of construction for this project is approximately $33.1 million, additional funds will be budgeted for in the 2000-2004 Capital Works Program.

There are no financial implications as a result of this report.

Recommendations:

It is recommended that this report be received for information.

Council Reference/Background/History:

By adoption of Clause No. 24 of Report No. 14 of the Environment and Public Space Committee on August 16, 1995, the former Metropolitan Council authorized funding and approval to engage a consultant to carry out a pre-design study incorporating the Class Environmental Assessment for the installation of residue management facilities at the R.C. Harris Filtration Plant, in order to comply with the Ontario Water Resources Act (RSO 1990).

At a meeting on May 7 and 8, 1997, the former Metropolitan Council adopted, with amendment, Clause No. 1 of Report No. 5 of The Environment and Public Space Committee. By adoption of this clause, the former Metropolitan Council authorized engagement of the firm of Dillon Consulting Limited to complete the above-mentioned work.

Since the engagement in June 1997, Dillon Consulting Limited have supported staff in carrying out the environmental assessment for the proposed project. This report provides information on the progress of the project with respect to the environmental assessment along with a description of the preferred method for managing the residues from the R.C. Harris Filtration Plant.

Comments and/or Discussion and/or Justification:

The R.C. Harris Residue Management Class Environmental Assessment (EA) was undertaken to identify and evaluate the preferred method of managing the residues which result from the treatment of Lake Ontario water for drinking water purposes at the R.C. Harris Filtration Plant in an environmentally responsible and cost-effective manner. The documentation for the EA process is summarized in "R.C. Harris Residue Management Project - Class Environmental Assessment Draft Report" dated June 4, 1999. The following information is mostly reproduced from the Executive Summary contained in the above-mentioned report.

The objective of the residue management project is to minimize the pollution of the environment associated with the discharge of water treatment residues from the R.C. Harris Filtration Plant. Currently, the R.C. Harris Filtration Plant discharges an estimated 750 to 1000 tonnes of solids mixed with 3500 to 5500 million litres of water back to Lake Ontario each year. Constituent parameters of the residue streams exceed the allowable Provincial Water Quality Objectives putting the City of Toronto in contravention of the Ontario Water Resources Act which is a chargeable offense under the Act.

The objective of the Class EA was to provide for an interactive and open approach to the planning process. This would allow the public and government agencies to become more familiar with the details of the proposed undertaking and to provide input into the decision making process. In addition, a key purpose of the consultation activities was to provide the City of Toronto with the opportunity to gather information concerning public and government agency perspectives, attitudes, concerns and potential impacts.

Since the beginning of the Residue Management Class EA in June 1997, there has been extensive public and agency consultation as follows: 17 meetings of the R.C. Harris Public Advisory Committee, three meetings of the Main Treatment Plant Neighbourhood Liaison Committee, three workshops dealing with evaluation criteria, short-listed options and Value Engineering, one joint stakeholders meeting, one agency meeting and two open houses. Through the public consultation, a list of alternative residue management options which may provide a solution to the identified need for the project was developed as shown in the table.

Option No.	Description
1	Treat On Site at R.C. Harris - full on-site treatment with trucking of dewatered residues to final disposal or beneficial re-use.
1st Variation	Treat On Site at R.C. Harris - treatment units are located on a lake fill site immediately adjacent to the R.C. Harris site.
2nd Variation	Treat On Site at R.C. Harris - treatment units are located inside two existing sedimentation basins.
2	Treat Off Site - equalization and pumping station at R.C. Harris site with forcemain to a treatment facility in the Port Lands area.
2a	Treat Off Site at the Main Treatment Plant (MTP)- equalization and pumping station at R.C. Harris site with forcemain to a treatment facility at the Main Treatment Plant site.
3	Treat in the Main Treatment Plant - equalization and pumping station at R.C. Harris site with forcemain to sanitary sewer on Queen Street and treatment being provided by MTP.
4a	Partially Treat On-Site, Send to MTP for Further Processing - equalization, clarification and pumping station at R.C. Harris site with forcemain to sanitary sewer on Queen Street and treatment being provided by MTP.
4b	Partially Treat On-Site, Send to MTP for Further Processing - equalization, clarification, thickening and pumping station at R.C. Harris site, with forcemain to MTP biosolids dewatering units for co-dewatering with biosolids
4c	Partially Treat On-Site, Send to MTP for Further Processing - equalization, clarification, thickening and pumping station at R.C. Harris site, with forcemain to MTP dedicated dewatering units. Dewatered residues would be sent to beneficial re-use with biosolids or kept totally separate.
4d	Partially Treat On-Site, Send to MTP for Further Processing - equalization, clarification and pumping station at R.C. Harris site, with forcemain to MTP dedicated thickening and dewatering units. Dewatered residues would be sent to beneficial re-use with biosolids or kept totally separate.
5	Operational and Maintenance Modifications - e.g., change coagulant type or backwashing procedures
6	Do Nothing

The estimated capital costs for the above options ranged from a low of $27.4 million for option 4d to $77.8 million for option 3.

The evaluation criteria used for the evaluation included the following nine criteria groups: heritage, cost, technical, natural environment, public health, social, recreation, local business, and planned land use.

The evaluation resulted in two options being recommended as more preferred - Option 2a, Off-site treatment at the MTP and Option 4c/d, Partial treatment at the R.C. Harris site and thickening/dewatering at the MTP site. These two options were presented to the R.C. Harris PAC, the MTP Neighbourhood Liaison Committee and a Stakeholder meeting in the spring of 1999. Following review of the evaluation, the advantages and disadvantages of each option and input received from public consultation, Option 2a - Off-site treatment at the MTP, which includes construction of underground storage tanks at the R.C. Harris site, installation of a 600 mm (24 inch) forcemain (pipe) from the Harris to the MTP with the residue processing at the MTP was brought forward as the recommended solution and presented at an Open House on June 8, 1999.

The estimated total estimated capital cost for "Option 2a - Off-site Treatment at the MTP Site" is $33.1 million. This cost is broken down as follows: construction at the Harris Plant - $8.9 million; 24" forcemain (pipe) from Harris to MTP - $9.4 million; and construction/upgrade at MTP - $14.8 million.

Option 2a has been identified as the recommended solution, for the following key reasons:

(a)Option 2a conserves the most space on the R.C. Harris site for future water quality process improvements and utilizes space at the MTP site which is not designated for any future use.

(b)Option 2a moves the treatment units off-site, thereby minimizing the heritage, recreational and social impacts on the R.C. Harris site and the neighbourhood.

(c)Option 2a has no impact on the sewage treatment or biosolids program at the MTP.

(d)Option 2a may utilize redundant buildings on the MTP site for dewatering of the residues.

(e)Option 2a will utilize either the existing outfall or the future outfall at the MTP, providing better dispersion of the clarified effluent than would be the case with the existing outfall at the R.C. Harris site if Option 4c/d was considered.

(f)In the short term, until the future outfall is constructed, any impact on the near shore water quality at the MTP can be avoided by temporarily suspending pumping of residue to the MTP during periods of peak flows at the MTP when the existing outfall is at its rated capacity. This short-term operational constraint can be managed by deferral of backwashes or using the equalization tank at the R.C. Harris site as a decant tank.

(g)Having all the treatment units at the MTP site, where there are well trained staff, familiar with wastewater treatment, will simplify control of the treatment process.

(h)Construction of the 600 millimetre (24 inch) diameter forcemain provides the maximum opportunity for linkages with other projects such as the shoreline stabilization project and the completion of the storm sewer interceptor from the R.C. Harris site to the Maclean detention tank.

(i)Option 2a addresses a number of relevant issues raised in the Mediator's Report dated April16, 1999 recently prepared subsequent to the Environmental Assessment for the Main Treatment Plant.

The impacts associated with the recommended solution can be fully mitigated through proper design and sound construction practices.

Currently, we are awaiting further comments from the public and agencies. The draft Class EA Report will be finalized by addressing any comments received and a notice of completion of the R.C. Harris Residue Management Class EA will be issued in August 1999. The final report will then be filed for the 30-day public review period. If no bump-up requests are filed or granted, then we will proceed to pre-design of the project. It is anticipated that the pre-design and detailed design will take place during 1999 to 2000 with the construction of facilities during 2000 to 2002.

Conclusion:

Following extensive public consultation through the environmental assessment process, a recommended solution has been identified for managing the residues from the R.C. Harris Filtration Plant in an environmentally responsible and cost-effective manner. The recommended solution consists of off-site treatment at the MTP which includes construction of underground storage tanks at the R.C. Harris site, installation of a 600 mm (24 inch) forcemain (pipe) from the Harris to the MTP and further processing at MTP.

Contact Name and Telephone Number:

Mr. H.A. Taniguchi, P. Eng.

Director, Water Supply

Phone: (416) 392-8220

Fax: (416) 392-3639

E-mail: htaniguchi@metrodesk.metrotor.on.ca

Michael A. Price, P.Eng., FICE

General Manager, Water and Wastewater Services

Barry H. Gutteridge

Commissioner, Works and Emergency Services

ADT/rah