Laserfiche WebLink
t27 June 2002 <br /> i AGE-NC Project No. 98-0520 <br /> ,Page4of8 <br /> Temperature, pH and.conductivity were measured at 1-gallon intervals, using an Oakton water <br /> '. analyzer to monitor pH, temperature and conductivity of the purged water; the field data logs are <br /> provided in-Appendix B. Purged water was temporarily stored on-site in 55-gallon drums. <br /> 2.2.2. Collection and Analysis of Ground Water Samples <br /> 1 Water samples were collected from the monitoring well.using new disposable bailers after allowing <br /> the wells to achieve a minimum 80% recovery of the pre-purge water volume. Each water sample <br /> ' was transferred into laboratory-supplied 40-m1 VOA vials containing 0.5 ml 18%hydrochloric acid <br /> as a sample preservative. After collection, the samples were properly labeled, placed in.a chilled <br /> container and transported under chain-of-custody to Cal Tech Environmental Laboratories(CTEL), <br /> ' a DHS-ccrtified laboratory, and analyzed"for; <br /> Total petroleum hydrocarbons,quantified as gasoline (TPH-g) in accordance with EPA <br /> Method 5030/8015M; i <br /> Benzene, toluene, ethyl benzene and 'xylene (BTEX) and for methyl tertiary- butyl ether <br /> (MTBE) - iri accordance with EPA Method 8020; and <br /> ' Fuel oxygenates,including tertiary butanol(TBA),di-isopropyl ether(DIPE),ethyl tert-butyl <br /> ether (ETBE), tert-amyl methyl ether (TAME), and MTBE, .with 1,2-dichloroethane <br /> ' (1,2-DCA) in accordance with'EPA Method 8260B. <br /> ' 2.3. , WELL HEAD SURVEY , <br /> ' On 05 March 2002, a California state-licensed survey engineer from Baumbach & Piazza, Inc. ' <br /> surveyed the elevation of a reference point on the top of the casings of ground water monitoring <br /> wells MW-6 through MW 10, respectively, to the nearest 0.01-foot relative to the City of Manteca <br /> ' Bench Mark Datum 963 at 3 3.75 8 feet above mean sea level (MSL). The results of the monitoring <br /> well survey are contained in Table 1. The surveying reports are presented in Appendix C. <br /> 3.0. FINDINGS <br /> ' Shallow site stratigraphy and groundwater elevation and flow direction were calculated•from field <br /> data.Hydrocarbon-impact to soil and ground water was inferred from laboratory analysis of the soil <br /> and ground water samples. ` <br /> Advanced GeoEnvironmentaI,Inc. <br />