GENERAL COMMITTEE–COMMUNITY SERVICES AND ENVIRONMENT
	TO:	Mayor and Members of Council
	FROM:	Peter Loukes, Director of Operations and Asset management
	PREPARED BY:	Stan Lau, Senior Project Manager
	DATE OF MEETING:	November 7, 2005
	SUBJECT:	Settlers Park Landfill Site Management – Status Update

RECOMMENDATION:

THAT the report entitled “Settlers Park Landfill Site Management – Status Update” be received;

AND THAT staff report back when the result of application to the Canada-Ontario Municipal Rural Infrastructure Fund is known.

PURPOSE:

The purpose of this report is to provide Council with an update on the Settlers Park Landfill Site Management program.

BACKGROUND:

On November 30, 2004, Council accepted staff recommendation to retain Beatty & Associates to carry out the following works:

· To carry out a leachate plume assessment in the vicinity of the Settlers Park Landfill site.

· To carry out a detail design for an Aerobic Landfill Management Plan.

Staff was also requested to report back in 2005 on the consultant’s finding and recommendations.

The consultant has completed the study and detail design and the results are outlined below:

Leachate Plume Impact Assessment:

· Groundwater Discharge To German Mills Creek

Inspection of the west bank of German Mills Creek revealed evidence of groundwater seepage along much of the creek between the north and south limits of Settlers Park. The seepage level, on average, is 20 to 30 cm higher than the stream. There is evidence that groundwater migrating from the landfill is continually discharging into the German Mills Creek.

The temperature profiling study indicates that the relative small mass of groundwater discharge, compared to flow in the stream, is too small to have a measurable thermal effect on the stream.

· Groundwater Quality

The June 2005 water samples from the stream bank well contained the same type of leachate parameters as previous 2003 and 2004 samples. Although some parameters such as calcium, iron, potassium, sodium, etc. show increasing concentrations each year, other indicators such chloride and hardness, show fluctuating concentrations.

Water from the two new piezometers which sample the groundwater discharge into German Mills Creek contained elevated leachate parameters, although the concentrations were generally lower than at the stream bank well.

· Impact on German Mills Creek

The water quality in German Mills Creek has been monitored annually since 2002. Water samples were collected upstream and downstream of the landfill. All samples were collected during the August to September low flow period when flow was measured in the range of 200 to 300 l/s.

The main leachate indicators which show minor increases in concentration between the upstream and downstream stations include chloride, calcium, manganese, zinc and ammonia. The increases in concentration are generally only a few percent and they vary from year to year.

Comparison of the upstream and downstream water samples indicates that the landfill leachate plume does not cause a significant impact to German Mills Creek. This is largely due to the fact that the low flow in the stream is several hundred times greater than the groundwater flux beneath the landfill.

Aerobic Landfill Management Plan:

· Aerobic Landfill Pilot Test

A pilot aerobic air injection test was carried out in July and August of 2004. Indicators of aerobic landfill conditions such as decrease in methane gas generation, increase in oxygen levels in the landfill, and the production of thermal energy (heat) were monitored in a network of gas probes.

The result of the pilot test indicated that the landfill temperature increase from 16 degree C to 26 degree C during the test period and gradual reduce to 21 degree C after about 6 months. Methane in the landfill around the test well decrease from 34% (by volume) to less than 5% and remain low for 11 days after completion of the air injection test.

The overall results of the pilot test demonstrated that it is feasible to reduce methane to non hazardous levels by utilizing Aerobic Landfill Technology.

· Aerobic Landfill Design

Implementation of the aerobic landfill technology requires the installation of a network of air injection wells. Atmosphere air is injected into the waste via the nests of wells by means of positive displacement air blowers. The air is distributed to the injection well by means of flexible surface piping.

Temperature and gas monitoring probes are required throughout the landfill to monitor the system performance. Automated monitoring using remote temperature loggers are required to ensure optimum conditions are maintained for aerobic decomposition.

· Leachate Recirculation System

In order to optimize the aerobic process, it is necessary to add moisture to the waste material. This is commonly done by installing an irrigation system on the landfill surface.

In this case, it is proposed to install a row of shallow well points along the west bank of German Mills Creek to intercept the leachate plume and then re-circulate onto the landfill by means of a drip irrigation system or shallow infiltration trenches.

This system will effectively eliminate the discharge of leachate into the German Mills Creek. As well, it will provide additional moisture to aid the aerobic process.

· Implementation Cost

The cost for implementation of the aerobic landfill and leachate recirculation system is estimated at $700,000.

DISCUSSION:

Implementation of Program:

Implementation of the aerobic landfill and leachate recirculation system will achieve the following objectives:

· Major reduction of greenhouse gas emission in Markham (estimated 1000 to 2000 tonnes of methane gas per year).

· Elimination of the risk of underground methane gas migration to the adjacent residences and the risk of fire and explosion.

· Elimination of leachate discharges to the German Mills Creek and contaminate the surface water.

· Reduce the waste decomposition and stabilization period from over 100 years to less than 20 years.

Potential Partnerships and Funding:

Canada-Ontario Municipal Rural Infrastructure Fund (COMRIF) – Intake Two:

Council on September 27, 2005, accepted a staff recommendation that the Settlers’ Park Landfill Management Program be submitted, as the Town’s highest priority, to the COMRIF – Intake Two program. An application was submitted to COMRIF prior to the submission deadline on September 30, 2005.

If the application to COMRIF is successful, the total project cost will be equally shared by the Federal Government, the Ontario Government and the Town of Markham at 1/3 each. An amount of $700,000 for this project is included in the Capital Works ROW 2006 Capital Budget request with funding of $ 233,333 from the Town, and $466,667 anticipated from COMRIF. If the 2006 capital submission for Settlers Park is approved, the project will proceed if the 2/3 COMRIF funding is received.

FCM Green Municipal Enabling Fund (GMEF): This project may qualify for funding contribution from GMEF. Staff will pursue funding opportunities in this regard.

Toronto and Region Conservation Authority (TRCA): Town staff have met with TRCA and have shared the findings of the studies with them. The TRCA has expressed interest in the project and may be willing to participate in the water quality monitoring program.

Ministry of the Environment (MOE): According to our consultant, the MOE has contacted them and has indicated wishes to monitor our program as they have other candidate site where this technique may apply.

ATTACHMENTS:

Attachment “A’ – Groundwater Flow

Attachment “B” – Air Injection and Leachate Infiltration System

Attachment “C” – Leachate Recirculation System

Attachment “D” – Aerobic Landfill and Leachate Recirculation System

Peter Loukes, P. Eng. Director, Operations and Asset Management

Jim Sales Commissioner, Community and Fire Services

Q:\Commission Share\Operations and Asset Management\Reports\2005\C & U\ROW\Other Report\Settlers Park Landfill Site Management Status Update.doc