Laserfiche WebLink
GROUND ZERO ANALYSIS, INC. <br /> 1714 Main Street <br /> Escalon, California 95320 <br /> Telephone: (209) 838-9888 <br /> Facsimile: (209) 838-9883 <br /> June 29, 2005 (D ECE�v J, <br /> Mr. Nuel Henderson <br /> JUN 3 0 2005 <br /> San Joaquin County Environmental Health Department EN\PR(SM�t4T HEALTH <br /> 304 E. Weber Ave., 3rd FloorR�� RVICES <br /> Stockton, CA 95202 <br /> Subject: Second Quarter 2005 Groundwater Sampling Report <br /> 102 South Wilson Way, Stockton, California (Figure 1) <br /> Dear Mr. Henderson: <br /> Ground Zero Analysis, Inc. (Ground Zero) has prepared this report to summarize fieldwork <br /> conducted at the subject site during the second quarter of 2005. Groundwater related activities <br /> • included monitoring groundwater elevations in all site wells and sampling groundwater from select <br /> site wells. On May 23, 2005, during a telephone conversation you instructed that for this event we <br /> would only need to sample wells that we feel are susceptible to evidencing plume migration. With <br /> this in consideration only monitoring wells MW8, MW 11, MW 12, MW 15A, MW 15B and <br /> MW 15C were sampled this quarter. <br /> Groundwater analysis consisted of total petroleum hydrocarbons as gasoline (TPHg), benzene, <br /> toluene, ethylbenzene and total xylenes (BTEX), 1,2 dichloroethane (1,2-DCA), ethylene <br /> dibromide (EDB), and gasoline oxygenate additives [methyl-tert-butyl ether (MTBE), ethyl-tert- <br /> butyl ether (ETBE), di-isopropyl ether (DIPS), tert-amyl methyl ether (TAME) and tert-butyl <br /> alcohol (TBA)]. <br /> The soil vapor extraction system was not in operation during the quarter. <br /> GROUNDWATER ACTIVITIES <br /> Groundwater Monitoring and Sampling <br /> Depth to groundwater was measured on May 24, 2005 in monitoring wells MW1 through MW16B <br /> and in vapor wells VW 1 through VW6. Depth to groundwater was then subtracted from each <br /> respective wellhead elevation to determine groundwater elevation. Water levels at the site rose an <br /> 40 average of 1.72 feet since the first quarter event in February 2005. The potentiometric surface was <br /> G:\GROUNDZE\ROEK\QMR\2005Qqtn2OO5.doe <br />