Laserfiche WebLink
California gional Water Quality Control Board � 6 <br /> Central Valley Region <br /> Katherine Hart., Chair <br /> Linda S. Adams 11020 Sun Center Drive#200, Rancho Cordova. California 95670-6114 Arnold <br /> Secretary for Phone(916)464-3291 • FAX(916)464-4645 Schwarzenegger <br /> Environmental http://www.waterb L1 V ID Governor <br /> Protection Ir"—'- 11 „ 511VV1 u <br /> Russell F. Chapin Sr. ll�ll lllllll "✓ 9 February 2010 <br /> Chapin Bros., Inc. FEB 1 2 2010 <br /> 1203 N. Charlton Avenue ENVIROWEINT HEALTH <br /> Stockton, CA 95203 PERMIT/SERVICES <br /> DOCUMENT REVIEW AND DIRECTIVES, CHAPIN BROTHERS INC., 1766 MONTE DIABLO AVE., <br /> STOCKTON, SAN JOAQUIN COUNTY, REGIONAL BOARD CASE NO. 390577 <br /> On 6 July 2009, a Regional Board staff letter directed semi-annual groundwater monitoring (SAGM) and <br /> resumption of groundwater extraction at your site. On 1 February 2010, you, your son Russell Chapin <br /> Jr., staff of your consultant Closure Solutions, Inc. (CSI) and Regional Board staff attended a meeting at <br /> our office. I reviewed the Meeting Summary (Letter) for that meeting, received 8 February 2010 and <br /> submitted by CSI. The Letter states that we discussed proposals for additional work to address data <br /> gaps, specifically potential future use of site groundwater and threats to human health from residual <br /> contamination. The Letter did not include a CSI proposed evaluation of additional remedial <br /> technologies. Regional Board staff proposed a limited first quarter 2010 sampling event, and directed <br /> shutdown of the groundwater extraction (GWE) system prior to sampling, to evaluate site conditions. <br /> The Letter proposes the GWE system shutdown and a groundwater sampling event of all wells with <br /> analyses limited to known contaminants of concern, during the week of 15 February 2010; and submittal <br /> of a SAGM report by 31 March 2010. The Letter also proposed the following scopes of work: <br /> • Conduct an updated sensitive receptor survey by 30 April 2010. <br /> • Contact California Water Service Company (CWSC) to assess potential groundwater usage, <br /> • Evaluate potential for groundwater plume migration and effectiveness of the GWE treatment system, <br /> and <br /> • Submit a workplan for a vapor intrusion survey / human health risk assessment by 30 April 2010. <br /> The Letter proposed schedule is approved; however, please provide a discussion of the effectiveness of <br /> the existing GWE system in the next SAGM (1St quarter) report, due 30 April 2010; and evaluate <br /> groundwater plume migration, determine need for additional remediation, and include the CWSC <br /> response in the following SAGM (3rd quarter) report, due 30 October 2010. Also provide email or letter <br /> status reports of all work conducted during the previous quarters (2nd and 4th quarters) by 15 July 2010 <br /> and 15 January 2010. If you have any questions, you can contact me at (916) 464-4615 or I can be <br /> reached by e-mail at jbarton(a�waterboards.ca.gov. <br /> sn <br /> ames L.L. Barton, P.G. <br /> Engineering Geologist <br /> cc: Nuel Henderson, San Joaquin County Environmental Health Department, Stockton <br /> Kathleen Waldo, Closure Solutions, Inc., 1243 Oak Knoll Dr., Concord 94521 <br /> California Environmental Protection Agency <br /> p�a Recycled Paper <br />