FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

' Emergency Remediation- 2480 Tracy Blvd., Tracy, CA. • Page 6 To permit an extended site investigation, which was included in the emergency plan to rapidly proceed, an application for a drilling permit was also submitted to the SJCPHS on April 3, 1996. It was issued by that regulatory authority on the same day. On April 5, 1996, Mr. Brett L. Hunter of Chevron U.S.A. Products Company's Northwest Region Site Assessment and Remediation Department in San Ramon, California was contacted to notify that company that contaminated soil and groundwater had been found in the subsurface of the adjacent property located down the groundwater gradient from the property at 575 West Grant Line Road where a Chevron service-station had previously been situated. Mr. Hunter was also briefed about plans for an emergency remediation program designed to permit timely continuation of construction of the new car-wash and lubrication-facility on the affected property at 2480 Tracy Boulevard. Contact with Mr. Hunter was maintained throughout the progress of the emergency remediation project and he was periodically apprised of the status of the work. He was provided with all pertinent data from sample analyses and other information gathered about the extent and characteristics of the contamination and the history of the site as soon as it became available. EXTENDED SITE INVESTIGATION The extended site investigation provided for in the emergency remediation plan was initiated by The San Joaquin Company on April 5, 1996. Health and Safety Plan The site investigation and all work to implement the subsequent remediation of soil and groundwater was performed according to the requirements of a site-specific health and safety plan included as an attachment to the Plan For Emergency Remediation. (Ref. 1.) The site-specific plan incorporated, by reference, all of the applicable directives of The San Joaquin Company's Master Health and Safety Plan (Ref. 2), a copy of which is on file with the SJCPHS. Geology and Hydrogeology The subject property and the surrounding area are situated on level terrain on the distal, northern slope of an alluvial fan. The underlying alluvial sediments are of Quaternary to Recent age. Observations in the excavations opened for construction of the new car-wash and lubrication-services facility revealed that the soil beneath the site - to a depth of at least eight feet - is a silty clay. Similar clastic materials, including clays, silty clays, sandy clays, silty sands, sands, and sands with gravel, are known to dominate the regional, near-surface strata to considerably greater depth than exposed by the excavations on the subject