SITE INFORMATION AND CORRESPONDENCE_1988-1991

Home Browse Search

MEMORANDUM . CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD - CENTRAL VALLEY REGION 3443 Routier Road, Suite A Phone: (916) 361-5600 Sacramento, CA 95827.3098 ATSS Phone: 8495-5600 TO: File FROM: Camilla Williams Engineering Geologist DATE: 12 July 1991 SIGNATURE: �LG1�rc��L� GrGnLIJ SUBJECT: REVIEW OF WELL SAMPLING FREQUENCY RECOMMENDATIONS, DEFENSE DISTRIBUTION REGION WEST (DORM), SHARPE SITE, SAN JOAQUIN COUNTY The "Remedial Investigation/Feasibility Study at DORM Sharpe Site, Well Sampling Frequency Recommendations" was submitted on 11 February 1991 by the U. S. Army Toxic and Hazardous Materials Agency (USATHAMA) . The Report was reviewed by Ton Vorster and Cam Williams. On 14 June 1991, I called Mr. John Guzman at the Sharpe Site to discuss our preliminary concerns with the Well Sampling Frequency Recommendation Report. I stated that the Board had several comments on the Report and that our comments would be sent out by letter in July. Mr. Guzman indicated that he had anticipated that the Board would have comments on the Report. In general , we are pleased that Sharpe has evaluated the data and has made proposals to streamline the monitoring program. Sharpe has collected a large ground water level and quality data base through the years and the revision to the monitoring program is overdue. Our review indicates that in general , Sharpe has included an adequate number wells in the quarterly monitoring program to define plume and monitor the effectiveness of the extraction system. However, we do have concerns with some of the specific wells listed for monthly, quarterly and annual monitoring. Our comments are discussed below. Page 1-1 . The Report states that the continuing monitoring program is required. 1 . To track the plume movement. 2. To validate the effectiveness of the treatment system. 3. To monitor potable supply wells. We concur that these are the objectives of the ongoing monitoring. However, Objective 1 should be expanded to include the assessment of the potential threat to downgradient receptors. Objective 2 should be expanded to include the optimization of the extraction and treatment systems. The objectives of the ongoing monitoring system should be further expanded to include the following. 4. To provide a long term strategy for ground water sampling and analyses which includes the constituents of concern, frequency and analytical methods.