SITE INFORMATION AND CORRESPONDENCE_FILE 1

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Mr. Edward C. Ralston Unocal Corporation August 24, 1995 Page 2 Approximate Date of Release The approximate date(s) of the release(s) is/are unknown. Date the Release was Discovered The release at Unocal Service Station No. 5886 was discovered in the field on July 27, 1995, during the removal of the stations fuel dispensers and associated piping. Partial verbal results were provided to Delta after 4:30 p.m. on Friday, July 28, 1995. Written results were received via fax beginning August 1, 1995. Unocal's compliance division confirmed the reported release and reported the confirmed discovery of the release on the USTURR form as July 31, 1995. Date Release was Stopped The possibility for release of hydrocarbons at the site was terminated on July 27, 1995, following the removal of the product piping. Description of Actions Taken to Stop the Release During the week of July 24, 1995, the associated fuel piping and fuel dispensers were removed from the site. The dispensers and associated piping will be replaced with new lines and dispensers. Description of Corrective Actions It is Delta's understanding that product was removed from the tanks and the associated product lines were rinsed out the week of July 24, 1995, prior to the demolition activities. The product dispensers were removed during the week of July 24, 1995, and the former product delivery lines were removed on July 27, 1995. Concurrent with the line removal, confirmation soil samples were collected beneath the former dispensers and along a minimum of every 20 linear feet of piping. Soil samples were also collected from two pits immediately adjacent to the former northern and southern canopy footings due to the observed visual presence of stained soil. Analytical results from the samples collected beneath the lines, dispensers, and from within the pits are presented in Table 1. Delta submitted a Work Plan for Corrective Action, dated August 18, 1995. This work plan proposes the installation of a minimum of 10 Geoprobe soil borings, the collection and analysis of both soil and ground water samples from the site, the removal of approximately 30 cubic yards of 3/4-inch drain rock used as backfill, observe line trenching on-site during construction activities, and the preparation of a report of findings. Based on the results of the proposed work, additional investigation/remediation will be performed as needed. Methods of Cleanup The initial field discovery (based on visual staining)occurred on July 27, 1995. Copies of the signed laboratory reports were received between August 10, and August 21, 1995. The work plan to perform an investigation to assess the lateral and vertical extent of hydrocarbons in soil and the lateral extent of hydrocarbons in ground water was submitted to the SJCPHS-EHD. Communication with the SJCPHS-EHD indicate that the earliest possible initiation of field work will be the week of