AECOM Report B&W - N - City of Guelph

City of Guelph2008 Annual ReportClosed Eastview Road Landfill SiteProbe GP00-06, located in the flowerbed adjacent to the scale house, has recorded methane concentrationsabove the LEL during all monitoring events since February 2006. In 2008, however, the methaneconcentrations were seen to be decreasing from previous years, with the December 2008 methaneconcentration measured at 9.3%. To ensure continued health and safety of staff and the public, the methanedetection and alarm systems in the scale house will continue to be maintained and calibrated asrecommended by the equipment supplier. If high gas concentrations persist in this area, installation of apassive gas venting system should be considered.In general, any construction activities undertaken in any on-site areas or buildings where gas may be presentshould be undertaken in accordance with the requirements of the Occupational Health and Safety Act andassociated regulations.6.4 Measured or Predicted Off-Site Occurrences of Combustible GasThere have been no measured or predicted occurrences of methane migrating off-site to date. Themonitoring program undertaken in 2009 should continue to assess the potential for off-site gas migration.6.5 Need to Implement Contingency PlansGiven the monitoring data and the physical setting of the site, there is a low likelihood of gas migration offsite.Therefore there is no need to implement a control system to address gas migration off-site.6.6 Adequacy of the Monitoring Programs and Recommended Changes6.6.1 Monitors Within the WasteGas concentrations in BH series monitors within the fill area should continue to be measured at least once inthe summer and once in the winter. Additional data may be collected to assist in assessment of gascollection system operation.6.6.2 Monitors Adjacent to the PLCCS (“C” and “D” Series Probes)The “C” and “D” probes should continue to be monitored for gas concentration at least twice a year.6.6.3 Buffer Lands Near the Property BoundaryThe ten “BH” probes, located in the buffer near the property boundary, should continue to be monitored atleast twice a year.(111414_2ra_apr29-09_city_of_guelph.doc) - 52 -