ARCHIVED REPORTS_2014 - Laserfiche WebLink

Home Browse Search

Landfill Gas The Monitoring and Reporting program for the landfill requires semi-annual VOC testing by EPA method TO-15 analysis. Soil gas samples were collected on February 14, 2014, and is included in this first semiannual report. Soil gas samples were collected in 1-liter Summa canisters and sent for VOC analysis. The concentrations of major gasses were recorded during the TO-15 sampling event, and a sample was collected from the probe most likely to have the highest VOC concentration. Methane concentrations were zero in all perimeter migration monitoring wells during the first quarter monitoring event. VOCs were detected in all four soil gas well probes during the first quarter monitoring event. The highest VOC concentration was found in the West Header of the landfill gas system as shown on Table 3. GROUNDWATER DIRECTION AND FLOW The general direction of groundwater flow, determined from the elevations of water in the groundwater wells, is to the south, and was consistent between quarters (Figure 2 and 3). Groundwater flow velocity was calculated to be about 77.39 feet per year with a gradient of 0.0023 feet per foot during the first quarter 2014. Groundwater flow velocity was calculated to be approximately 84.16 feet per year with a gradient of 0.0025 feet per foot during the second quarter 2014. (Appendix F). STANDARD OBSERVATIONS The site was inspected monthly throughout the monitoring period. The information on the original field form was transcribed for legibility. Transcribed and original handwritten forms are attached (Appendix G). MRP Section B—Facility Moniotoring - requires that the site be inspected after a "significant" storm event, which is indicated by rainfall 1.4 inches or more within a 24-hour period, as measured at the Peanut Hill meteorological station. Rainfall of that intensity did not occur during this monitoring period. IRUN-OFF/RUN-ON FACILITIES General The HLSL utilizes a single facility to control run-off and run-on: a perimeter berm/road surrounding the site, which generally prevents any water from entering the site. Water drains from the landfill property to a retention pond. A discharge to the Waters of the State occurs when discharge pumps are manually activated, discharging water from the retention ponds. No such discharge occurred in this monitoring period. Hamey Lane Sanitary Landfill 7 Department of Public Works/Solid Waste 1"Semiannual 2014 Groundwater Monitoring Report County of San Joaquin—July 31,2014