Laserfiche WebLink
4 SUMMARY OF FINDINGS <br /> Philip continues to monitor subsurface conditions and the plume of gasoline-impacted <br /> groundwater at the Earthgrain's facility Philip's data from this current monitoring <br />' event, and from previous assessments indicates that the plume of groundwater <br /> impacted with detectable hydrocarbons is approximately 100 feet wide, and some 550 <br /> feet long, elongated in the same east-northeast direction as groundwater flow The <br /> highest concentrations of petroleum hydrocarbon compounds are centered near the <br /> former gasoline USTs, and around wells MW-1, SP-1, and PZ-I <br /> IThe lateral extent to the north, south, and west had been delineated by historic, non- <br /> detectable,petroleum concentrations measured in groundwater samples collected <br /> from wells in those directions To the east, a TPH-G concentration of 100 µg/l was <br /> measured in a groundwater sample collected from CPT-3 during the May 1999 site <br /> investigation This CPT-3 sample did not contain benzene, and Acculabs had <br /> characterized the TPH-G analysis as being uncharacteristic of a typical gasoline, <br /> suggesting that the impact was more characteristic of degraded petroleum <br /> The oxygenate compound DIPE has been detected in samples collected from wells in <br />' close proximity to the source TBA was detected in one groundwater sample collected <br /> from a source well TBA had only been detected one previous time Philip will <br /> continue to monitor oxygenate levels to assess site conditions <br /> Philip and Earthgrains are planning to install an air-sparging and soil venting <br /> remediation system to augment natural degradation and initiate petroleum <br /> hydrocarbon source removal in the vicinity of the former gasoline USTs The <br /> workplan for this system has been approved by PHS/EHD Philip has applied for an <br /> air permit to operate this system, but have been notified by the local air management <br />' district that a 4-month period may be required before permits are authorized Based <br /> on this waiting period, it may be at least until February 2001 before the system can be <br /> installed and operated <br /> 1 <br /> 10 <br /> October 2000 <br /> Groundwater Monitoring Report <br /> The Earthgrams Company <br /> 2651 South Airport Way <br /> Stockton,California <br /> Prepared for THE EARTHGRAINS COMPANY Prepared by Philip Services Corp <br /> H1ENV%624001321121382EG15tockton\StocktonVOWmondoe November 10,2000 <br />