Laserfiche WebLink
Mr. John Trinkle - 2 - 16 December 2008 <br /> Table 1. Soil and Groundwater Analytical Matrix <br /> Volatile Carbamate/Urea <br /> Organic Compounds, Chlorinated Organophosphate Organochlorine <br /> Compounds including Diuron Herbicides Compounds Compounds <br /> (EPA 826013) (EPA 632) (EPA 8151) (EPA 814 1) (EPA 8081) <br /> Soil X X X <br /> Groundwater x X X <br /> The Work Plan proposes obtaining grab groundwater samples from each of the monitoring <br /> well borings. Since Trinkle and Boys will be obtaining groundwater samples from the <br /> monitoring wells, it will not be necessary to also obtain grab groundwater samples. <br /> Missing Monitoring Wells <br /> Monitoring wells MW-1, MW-2, and MW-3 were installed in 1989, and disappeared sometime <br /> between 1991 and 2008. Trinkle and Boys proposes to use ground penetrating radar to <br /> conduct a subsurface search of the areas where monitoring wells are recorded to have been. <br /> Regional Water Board staff concur with this approach. <br /> Summary <br /> Regional Water Board staff conditionally concur with the Monitoring Well Installation Work <br /> Plan, subject to the following changes. <br /> • Provide a diagram illustrating a revised location for proposed monitoring well MW-4 for <br /> Regional Water Board staff concurrence. The diagram may be transmitted electronically. <br /> • At least one soil sample should be obtained from each boring at about three feet below <br /> ground surface. <br /> • Trinkle and Boys should, at the minimum, follow Table 1 for soil and groundwater sample <br /> analyses. <br /> In a 11 December 2008 telephone conversation with Mr. Daniel Villanueva of Advanced <br /> GeoEnvironmental, we agreed that the field work could begin within 60 days of this letter, and <br /> an investigation report prepared 60 days after the field work was completed. Therefore, please <br /> provide a Well Installation and Geophysical Investigation Report by 17 April 2009. <br /> If you have any questions, you may contact me by telephone at (916) 464-4680 or by email at <br /> aterrell(a-)waterboards.ca.gov. <br /> AIMY ITERRELL <br /> Private Sites Cleanup Unit <br /> Enclosure <br /> cc: Mr. Harlin Knoll, San Joaquin County Environmental Health Dept., Stockton <br /> Mr. Mike Lehr, MCR Engineering, Inc. Manteca <br /> Mr. Robert Marty, Advanced GeoEnvironmental, Inc., Stockton <br />