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STATUS OF ACTIVITIES AT THE SITE A Problem Assessment Report (PAR) for the site was issued on 19 December 1991 The PAR summarized activities conducted at the site since the discovery in December 1986 of petroleum hydrocarbons in the site soil from two, underground storage tanks Included in the PAR was a summary of investigations conducted at the site from April 1987 until present to determine the extent of soil and groundwater contamination Additionally, a summary of soil remediation activities was also included in the PAR Remediation of groundwater contamination at the site has not yet been conducted, but is proposed Until a groundwater treatment system is on-line, the San Joaquin County Environmental Health Department has requested that quarterly groundwater monitoring be conducted in accordance with the State of California Regional Water Quality Control Board's Underground Storage Tank Regulations GROUNDWATER SAMPLING Sampling of the Rambo Bakery groundwater monitoring wells was conducted on 9 April 1992 Due to recent drought conditions, only five of the eight monitoring wells contained enough water to allow samples to be obtained Consequently, only monitoring wells MW-1, MW-2, MW-3, MW-6 and MW-8 were sampled in April 1992 Initial groundwater data was obtained prior to beginning the sampling Static groundwater elevations for each well were first measured and recorded The elevations were used to calculate the groundwater gradient and to gauge well recharge following purging of the wells The temperature, conductivity and pH of the groundwater in each well was also measured and recorded This data was used to gauge the well purging operations Following collection of the initial data, all five wells were purged using a teflon bailer The extracted groundwater was containerized in a 55-gallon drum stored on the site Three to five well volumes of water were extracted from each well, 0 25 gallons from MW-2 and MW-3, 2 0 gallons from MW-8, 3 0 gallons from MW-6 and 24 gallons from MW-1 Due to the low groundwater levels in the wells, all but MW-1 were virtually depleted of groundwater Following completion of the well purging, measurements of the groundwater temperature, conductivity and pH for each well were obtained and recorded The wells were then allowed to recharge to 85% of their original groundwater level Upon adequate recharge, the wells were sampled via a teflon bailer The groundwater samples were placed in sterile containers, stored on ice and transported to a State of California certified analytical laboratory Laboratory analyses were conducted for total petroleum hydrocarbons (method 8015 modified/purge and trap), aromatic volatile organics (EPA method 602) and total lead (EPA method 6010) FIELD DATA AND SITE DETERMINATIONS The site-specific groundwater gradient for April 1992 was calculated based on the static groundwater elevations measured prior to well purging Based on the measurements, the groundwater gradient for April 1992 was calculated to be toward the east/northeast (see Figure 2) The groundwater gradient calculation worksheet is included at the end of this letter ANDERSON CONSULTTININ / CONSUG V GROUP