ARCHIVED REPORTS_XR0002070 - Laserfiche WebLink

Home Browse Search

ri a GROUND ZERO ANALYSIS, INC. 1714 Main Street Escalon,California 95320-1927 Telephone (209)838-9888 Facsimile (209)838-9883 July 18, 2003 Mr Harlin Knoll San Joaquin County Environmental Health Department 304 East Weber Avenue, Third Floor Stockton, CA 95202 Subject Second Quarter 2003 Groundwater Monitoring Report Knowles Property, 1140 W Hammer Lane, Stockton, CA Dear Mr Knoll • This report summarizes activities at the subject site (Figure 1) during the second quarter 2003 Activities conducted during the reporting period included monitoring depth to water in all site wells, purging and sampling wells MW1, MW4 and MW5, and analyzing groundwater samples for benzene, toluene, ethylbenzene, total xylenes (BTEX), and total petroleum hydrocarbons as gasoline (TPHg) SITE ACTIVITIES Groundwater Monitoring and Sampling An experienced Ground Zero technician measured the depth to groundwater in each site well on May 27, 2003 The depth to groundwater beneath the site ranged from 32 95 feet below the top of the well casing (btoc) in well MW3 to 34 58 feet btoc in well MW2 Groundwater elevations in site wells rose an average of 0 90 feet between February 10, 2003 and May 27, 2003 The water table beneath the site lies above the screened intervals in all wells except well MW3 Groundwater flow was generally toward the east with a calculated gradient of 0 0016 feet per foot, or approximately 8 4 feet per mile A potentiometric surface map for May 27, 2003 is presented on Figure 2 Monitoring well construction details are summarized 1n Table 1 Groundwater monitoring data are summarized 1n Table 2 A Ground Zero technician purged a minimum of three well casing volumes of groundwater from monitoring wells MW1, MW4 and MW5 on May 27, 2003 Temperature, specific G 1GROUNDZEIKNOWLES HAMIREPORTSIQMR12QM2003 doc