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KNOWLES MEETING -2- lower levels of BTX&E with benzene at 2 . 0 to 6 . 0 ppb. TPH (gas) was found at slightly lower levels for wells 1 and 3 (180 to 210 ppb) but at higher levels for well 2 (720 ppb) . Numerous domestic and municipal wells are located near the site (see attached map and table) . Sampling of two small system municipal wells (Oakridge Shopping Center) on 16 June 1957 showed 0. 5 and 0. 6 ppb benzene and the SJL.HD has requested the owner of Oakridge Shopping Center to monitor the wells. Subsequent sampling of the Oakridge wells and other nearby wells by RWQCB staff has showed no detectable benzene. Soil and groundwater contamination is being assessed at a nearby Exxon station (909 W. Hammer Lane) but no relationship between the Exxon and Knowles sites has been determined. Ted Knowles stated that he has operated the station since approximately 1960 and that inventory records indicate no product loss. No tank test data have been submitted. Ted Knowles has requested approval from the SJLHD for the construction of a new service station. Delay in the construction has severely reduced the influx of revenue to the. Knowles business and future remediation work at the site would be difficult without operation of the new station. A workplan prepared by Groundwater Technology (GTI) pr_opcses to investigate potential sources of contamination at the site and to monitor the on-site wells. The source investigation will involve drilling and sampling of one deep boring at the old tank pit and drilling and sampling of shallow borings near the old product lines and pump stations. Ground water monitoring will ins*oive monthly measurements of water 'Level to determine gradient and quarterly sampling for BTX&E and TPH (gas) . GTI will. make sure that locking caps are on the monitoring wells. Construction for the new service station is acceptable provided a map is submitted showing the current construction plan and the old tank, product lire, and pump station locations; the work plan is imnlemented; a Preliminary Report is prepared; and a. letter of commitment to define the extant of contamination if necessary, perform necessary remediation, and prepare a Problem ?assessment Report (if necessary) is received within 30 days of local agency approval of the construction plan.