Laserfiche WebLink
cnc� n <br /> Z ? z <br /> CD <br /> o i sr� ' SERVICES, WCORPORATEI3 <br /> {✓ <br /> i <br /> [P— <br /> -ji'l,11,329 <br /> P11 r. <br /> ] <br /> MPDS-UN6981-06 <br /> February 22 , 1995 <br /> Unocal Corporation <br /> 2000 Crow Canyon Place, Suite 400 <br /> P.O. Box 51.55 <br /> San Ramon, California 94583 <br /> Attention: Mr. David J Camille <br /> RE. Quarterly Data Report <br /> Unocal Service Station #6981 <br /> 4707 Pacific Avenue <br /> Stockton, California <br /> Dear Mr. Camille : <br /> This data report presents the results of the most recent quarter of <br /> monitoring and sampling of the monitoring wells at the referenced site <br /> by MPDS Services, Inc . <br /> RECENT FIELD ACTIVITIES <br /> The monitoring wells that were monitored and sampled during this <br /> quarter are indicated in Table 1 . Prior to sampling, the wells were <br /> checked for depth to water and the presence of free product or sheen. <br /> The monitoring data and the ground water elevations are summarized in <br /> Table 1 . The ground water flow direction during the most recent <br /> quarter is shown on the attached Figure 1 . <br /> Ground water samples were collected on January 25 and 26, 1995 . Prior <br /> to sampling, the wells were each purged of between 5 and 16 . 5 gallons <br /> of water. During purging operations, the field parameters pH, <br /> temperature, and electrical conductivity were recorded and are <br /> presented in Table 2 . Once the field parameters were observed to <br /> stabilize, and where possible, a minimum of approximately four casing <br /> volumes had been removed from each well, samples were then collected <br /> using a clean Teflon bailer. The samples were decanted into clean VOA <br /> vials and/or one-liter amber bottles, as appropriate, which were then <br /> sealed with Teflon-lined screw caps, labeled, and stored in a cooler, <br /> on ice, until delivery to a state-certified laboratory. MPDS Services , <br /> Inc transported the purged ground water to the Unocal Refinery located <br /> in Rodeo, California, for treatment and discharge to San Pablo Bay <br /> under NPDES permit . <br /> ANALYTICAL RESULTS <br /> The ground water samples were analyzed at Sequoia Analytical Laboratory <br /> and were accompanied by properly executed Chain of Custody <br /> documentation The analytical results of the ground water samples <br /> collected to date are summarized in Tables 3 and 4 The concentrations <br /> of Total Petroleum Hydrocarbons (TPH) as gasoline and benzene detected <br /> 2401 Stanwell Drive Sprite 300 Concord,CA 94520 <br /> TEL (510)602-5120 FAX (510)689-1918 <br />