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Mr. Dan Johnson <br /> December 29, 2004 <br /> Page 2 <br /> At higher concentrations, methane is flammable. However, the presence of methane gas in site <br /> soil does not mean there is an immediate threat of explosion because flames cannot typically <br /> propagate through soil. <br /> Surface Emissions Monitoring <br /> On November 9, 2004, surface emissions monitoring was performed over the surface of the <br /> subject site. The intent of the monitoring was to identify any specific locations or areas of the <br /> landfill surface with organic compound concentrations exceeding SJVAPCD Rule 4642 <br /> threshold limit value of 1000 ppmv measured as methane. <br /> Emissions Testing Instrumentation/Calibration <br /> Instruments used to perform the landfill surface emission testing consisted of the following: <br /> • Century Organic Vapor Analyzer(OVA) Model 108 portable Flame Ionization <br /> Detector(FID). This instrument measures methane in air over a range of 1 to 10,000 <br /> ppmv. The OVA meets SJVAPCD requirements and was calibrated in accordance <br /> with Rule 4642 Section 6.1.1.1 test methods. <br /> • Davis Instruments Weather Wizard III Anemometer with continuous data recorder for <br /> meteorological conditions in accordance with SJVAPCD Rule 4642 Section 6.1.1.3. <br /> Instrument calibration logs are shown in Attachment 2. <br /> Surface Emissions Monitoring Procedures <br /> Surface emissions monitoring was conducted in accordance with SJVAPCD Rule 4642 Section <br /> 6.1.1.2. Monitoring was performed with the OVA inlet held within 3 inches of the landfill <br /> surface while a technician walked a grid in parallel paths not more than 90 feet apart over the <br /> surface of the landfill. Cracks, holes and other breaks in the surface were also tested. Surface <br /> emissions readings were recorded approximately every 30 seconds or when significantly <br /> different values were measured. <br /> During surface emissions testing,wind speed was recorded using the on-site anemometer. <br /> Recorded wind speed results are shown in Attachment 1. Wind speed averages were observed to <br /> remain below 10 miles per hour and no instantaneous speeds exceeded 15 miles per hour. No <br /> rainfall had occurred within 72 hours of the monitoring events. Therefore, site meteorological <br /> conditions were within the modified Rule 4642 requirements on the test date. <br />