ARCHIVED REPORTS_2009_1 - Laserfiche WebLink

Home Browse Search

Mr. Todd Del Frate - 2 - SECOND 2 - SECOND SEMESTER 2009 GROUNDWATER AND SURFACE WATER MONITORING REPORT; FOOTHILL SANITARY LANDFILL Two VOCs were reported in well MW-3: TCE at 1 ppb and DCE at trace concentration. The County continues to be concerned that installation of impermeable liner over refuse decreases the potential venting of LFG in spite of the presence of a LFG collection system. Sealing the refuse from the air can prevent the escape of LFG, forcing LFG into the soil where impact to groundwater can occur. Perhaps such low concentrations will immediately dissipate. Regardless, the County will improve the piping (and increase LFG collection) from the two LFG wells that serve the portion of the landfill near MW-3. The County has been collecting gas from the soil gas trench beneath the Module 1 liner since October 2009. Methane content has decreased from 25% to near zero during that time. Surface water from the creek on the eastern property boundary was sampled this year. Results from the upstream and downstream samples were similar, indicating no noticeable impact by surface flow from the landfill property. I certify under penalty of law that I have personally examined and am familiar with the information submitted in this document and all attachments and that, based on my inquiry of those individuals immediately responsible for obtaining the information, I believe that the information is true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment. If you have any questions, please call me at (209) 468-8504. Sincerely, W. MICHAEL CARROLL, PE Senior Civil Engineer WMC:kb NAI Foothill\Groundwater Mon itoring\Repts2009\2nd Sem\FH 2ndSem091etter.doc Enclosure c: Robert McClellon, Environmental Health Department LA 31610