AECOM Report B&W - N - City of Guelph

City of Guelph2008 Annual ReportClosed Eastview Road Landfill SiteMonitor D4-I, adjacent to MH 4S and between the waste and sheet pile wall, measured gas concentrationsbelow LEL during all 2008 monitoring events. MH 4S, however, showed gas concentrations above LELduring two monitoring events in 2008.Monitors C9-II, C10-II and C11-II located beyond the sheet pile wall in the southeast corner of the site,consistently measured no methane in 2008.Monitor D5-I, located upstream and midway between MH AS and MH BS on the east side of the site,measured gas concentrations below LEL during 2008 monitoring events. MH AS and MH BS both containedno methane during 2008 monitoring events.Monitors C12-I, C13-I and C14-I located between the PLCCS and the property boundary, recorded nomethane during all 2008 monitoring events.The above noted trends continue to indicate that some landfill gas migrates from the waste toward thePLCCS where it is intercepted and vented to the atmosphere.Buffer Lands Near the Property BoundaryTen “BH” monitors are located in the landfill buffer zone to document gas concentration near the propertyboundary. Monitoring results, as shown in Table E4 of Appendix E, indicate that landfill gas has not migratedto the property boundary to date.Southwest Corner of the SiteSix “GP” probes monitor for gas migration and soil-gas conditions adjacent to on-site buildings. Table E5 ofAppendix E presents methane measurements at the GP series probes.At GP97-1, near the southwest property boundary, there was no methane recorded during four occasions in2008. Since 1997, methane concentrations have never exceeded LEL. It is therefore concluded thatmethane migration off-site is not occurring in this area.At probe GP97-3, north of the Storage Building, gas concentrations in 2008 were measured to be above theLEL on one event, and below the LEL on the other three events. This may be the result of the presence ofwaste or putrescible materials in the area.At probe GP97-4, northeast of the Administration Building, gas concentrations in 2008 were consistently zero.At probe GP97-5, north of the maintenance shed, there was no gas measured during each monitoring eventin 2008.At probe GP00-07 located adjacent to the Main pump station, no methane was measured during allmonitoring events in 2008.(111414_2ra_apr29-09_city_of_guelph.doc) - 51 -