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Site History Jackpot Food Mart, 1434 W Yosemite Ave,Manteca CA Time Oil Property No 04167 A copy of SECOR's "Quarterly Monitoring Report, July- September 1995"was forwarded to the PHS/EHD and CRWQCB on December 14, 1995 (quarterly Status Report - Fourth Quarter 1995 Groundwater Sampling Results On December 5, 1995, samples were collected from each of the groundwater monitoring wells (W-3 and W-5 through W-7) at the subject site Prior to purging, the depth to water in each well was measured to evaluate elevation, flow direction, and gradient Groundwater with a southwesterly flow at a rate of 0 001 ft/ft was encountered in the wells at depots of 15 10 feet to 16 12 feet below ground surface Since the previous sampling event, groundwater elevation increased in each of the wells by 0 90 feet to 1 24 feet, or an overall average increase in groundwater elevation of 1 08 feet across the site Groundwater flow direction changed from northeast to southwest, however, gradient remained consistent with previously collected data The variations in groundwater elevation and direction are most likely due to seasonal variation Analyses did not indicate presence of hydrocarbons in any of the samples collected from the wells Remedial Actrvrtres Although a permit was received from the San Joaquin County Unified Air Pollution Control District for the construction of a vapor extraction system to remediate soils beneath the site, Time Oil was aware that the PHS/EHD is currently considering changes in cleanup requirements for petroleum-impacted sites which pose little or no risk to potential receptors Because groundwater at the subject site has not been impacted, and soil impacts appear to be only residual, Time contacted the PHS/EHD to discuss and re- evaluate the need for the installation of the currently proposed remediation system Based on that telephone conversation, it was Time's understanding that 1 The PHSIEHD considers the hydrocarbon impacts at the subject site to be minimal, limited to soils, and "low risk" 2 Based on the PHS/EHD's current direction with respect to "soil only" sites, the installation of the proposed remediation system will not be required at this time 3 The PHS/EHD will not grant site closure at this time, however, they will permit Time Oil to submit a workplan for verification soil sampling which includes an evaluation of the propensity for natural attenuation of hydrocarbons beneath the site to occur 4 Because adequate groundwater data has been collected, bi-annual groundwater sampling (rather than quarterly groundwater sampling), may be conducted until closure of the site has been granted Time Oil's Fourth Quarter 1995 status report was forwarded to the PHS/EHD and CRWQCB on February 1, 1996 A copy of SECOR's "Quarterly Monitoring Report, December 1995"was forwarded to the PHS/EHD and CRWQCB on February 13, 1995 Quarterly Status Report - First Quarter 1996 and Submittal of Workplan for Additional Environmental Investigation Groundwater Sampling Results- First Quarter 1996 Because groundwater at the subject site had not been impacted, and soil impacts appeared to be, residual, Time contacted the PHS/EHD in January 1996 to discuss the need for active site remediation and potential changes to the current quarterly groundwater monitoring program At that time, the 6