Laserfiche WebLink
r <br /> GROUND ZERO ANALYSIS, INC. <br /> 1714 Main Street 2006 MAY 19 PM : 35 <br /> Escalon, California 95320 <br /> Telephone (209)838-%88 SAP: C Q,1 N T Y <br /> Facsunxle (209)$3&9883 E N VI�;'J J t Z f: i 1;L <br /> HEALTHDE►'.. KTHLNT <br /> May 18, 2006 V Ott <br /> Ms Vicky McCartney (/ 0 <br /> San Joaquin County Environmental Health Department <br /> 304 E Weber Ave , Third Floor <br /> Stockton, CA 95202 <br /> Subject First Semi-Annual 2006 Groundwater Monitoring and Sampling Report <br /> H&H Engineering and Construction Facility, 212 Industrial Drive, Stockton, CA <br /> Dear Ms McCartney <br /> This letter report summarizes the results of the first semi-annual 2006 groundwater monitoring and <br /> sampling activities at the subject site A site location map is presented on Figure 1 <br /> Site Activities <br /> Activities at the site included monitoring water Ievel elevations, and purging and sampling <br /> groundwater from all site wells Groundwater samples were analyzed for benzene, toluene, <br /> ethylbenzene and total xylenes (BTEX), total petroleum hydrocarbons as gasoline (TPHg) and 1,2 <br /> dichloroethane (1,2-DCA) <br /> Groundwater Monitoring and Sampling <br /> On May 9, 2006 monitoring wells MW 1 through MW3 were monitored and sampled Groundwater <br /> elevations were calculated by measuring the depth to groundwater in each well and subtracting from <br /> the respective wellhead elevation Groundwater elevations at the site rose an average of 5 98 feet <br /> since last monitored on August 19, 2005 The average hydraulic gradient across the site was <br /> approximately 0 009 ft/ft (47 feet per mile) Groundwater flowed in a northeasterly direction A <br /> potentiometric surface map is depicted on Figure 2 Groundwater monitoring data are summarized <br /> in Table 1 Monitoring data sheets are included in Attachment A <br /> Prior to sampling, monitoring wells MW 1 through MW3 were purged of a minimum of three well <br /> casing volumes During the purging process, temperature, pH and electrical conductivity parameters <br /> were measured Samples were collected after parameter stabilization, and 96-100% water level <br /> recovery Groundwater samples were delivered under chain of custody protocol to Argon <br /> Laboratories (ELAP #2359) for analysis of TPHg by EPA Method 8015M, BTEX by EPA Method <br /> 802113, and 1,2-DCA by EPA Method 8260B Purge water was contained in a properly labeled r <br /> G 1GROUNDZEIW-EISAR1200611 SAR06 doc <br />