Laserfiche WebLink
Mr. Robert Trommer <br /> Comments on CUF Site Closure Recommendations for Various Sites March 3, 2010 <br /> Claim No. 17042 - 15406 S Tracy Blvd Tracy <br /> This site has persistent moderate TPHg, and low ethylbenzene and xylenes contaminants in <br /> one well, MW-4. Wells toward the north, east and south are not impacted; there are no <br /> delineating wells toward the west. A domestic well is located approximately 135 feet southwest <br /> of MW-4. In November 2009 limited groundwater extraction (GWE) was implemented utilizing <br /> MW-4. Approximately 15,000 gallons were extracted from the well. Since then the well has <br /> been monitored monthly; concentrations were reduced, but may be rebounding. The consultant <br /> plans to complete the rebound testing with the March sampling event and then prepare a report <br /> of findings. The plume appears to be of limited extent, except toward the west, which is not <br /> characterized. Significantly impacted soil has not been encountered on the site. There does not <br /> appear to be a significant contaminant mass present, but the contaminants are persistent and <br /> there is a domestic well to protect. The EHD will issue a directive to prepare a site closure <br /> summary report, addressing plume delineation and evaluation of vapor intrusion and health risk <br /> issues, threat to the domestic well, and other site closure concerns. If a favorable report is <br /> received, the EHD anticipates site closure in nine to twelve months. <br /> Claim No. 17179 - 15 E. Grant Line Road Tracy <br /> Dissolved contaminant concentrations have declined to levels suitable for site closure <br /> consideration. The consultant has recently obtained grab groundwater samples to complete the <br /> lateral and vertical delineation of the site, and the results are pending. The EHD will direct <br /> completion of a vapor intrusion evaluation. Upon receipt of the results of the recent grab <br /> groundwater investigation and the vapor intrusion evaluation, the EHD will initiate the site <br /> closure process if warranted by the additional information. The EHD anticipates site closure may <br /> be obtained in six to twelve months. <br /> Summary <br /> The EHD will be moving these sites to closure as rapidly as possible. The EHD has responded <br /> previously to the CUF on these sites in response to the five-year reviews and the annual <br /> updates. Direct comments from the CUF technical staff on the concerns expressed on the more <br /> problematic sites above are requested (specifically Claim Nos. 8431, 7709, 11775, 14118, <br /> 14349, 14353, 15211, 15890, and 17042). An EHD representative is available to meet with <br /> your technical staff if that would be helpful. <br /> If you need more information to complete your evaluation of these cases, please contact Nuel <br /> Henderson, Engineering Geologist, at (209) 468-3436, or nhenderson@sicehd.com. <br /> Sincerely, <br /> Nuel C. Henderson, Jr., PG Adrienne Ellsaesser, REHS <br /> Engineering Geologist Acting Program Coordinator <br /> Comments on CUF Site Closure Recommendations 0310.doc <br /> i <br />