Laserfiche WebLink
� I <br /> ENVIRONMENTAL RISK SERVICES <br /> CORPORATION T - <br /> April 25, 2013 <br /> Phil Giovannini <br /> RWQCB-CVR <br /> 11020 Sun Center Drive, Suite 200 <br /> Rancho Cordova, CA 95670 <br /> RE: Work Plan for Well Destruction, Roberts No.1 Dredge Sediment Placement Facility, <br /> Lower Robert's Island, San Joaquin County, California <br /> Dear Mr. Giovannini <br /> The Port of Stockton has conducted ground water monitoring in association with the Roberts <br /> No.1 (RN1) dredge sediment placement area under Waste Discharge Requirements Order No. <br /> R5-2006-0078. A total of 44 wells were installed and monitored on a quarterly basis at RN1 from <br /> 2006 through 2008. The order was amended in 2008 in a letter from the Regional Water Quality <br /> Control Board—Central Valley Region(Board) to include annual monitoring of 18 of the 44 total <br /> wells. <br /> While the original order was intended to monitor the effects from the placement of sediment <br /> from Docks 14 and 15 from the Port of Stockton (Port), dredge sediment is placed at RN1 from <br /> the Stockton DWSC and maintenance dredging of the Port's docks on an annual basis. In <br /> addition, deepening of the Port's West Complex docks has been proposed for placement at the <br /> RN1 facility. The continued monitoring of the RN1 facility is recommended to evaluate impacts <br /> from dredge sediment placement. <br /> However, since 2008, a number of the wells are inactive and some of the 18 wells in the <br /> monitoring program have been damaged or become inaccessible due to site activities. The <br /> following recommendations are proposed to streamline and improve the annual monitoring <br /> program at the RN1 site. <br /> • Because wells at MW-1 through MW-4, MW-13 through 17, and MW-20 have not been <br /> accessed for a period of nearly 5 years, it is recommended these wells are abandoned as <br /> described below. <br /> • Wells MW-12d, r, and s are suitable replacement wells for MW-6d, r and s and are in <br /> better condition. It is recommended that the MW-6 wells are abandoned and MW-12 <br /> wells are added to the monitoring program. <br /> 1600 Riviera Avenue,Suite 310,Walnut Creek,California 94596 a rs <br /> 925 938 1600-erscorp.us <br />