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A �AI3RIA Constant rate test recovery data from well S-1 were analyzed by the Theis Recovery method to estimate the hydraulic conductivity and transmissivity of this water-bearing zone The results should be considered approximate for the reasons previously discussed The hydraulic conductivity and transnussivity yielded from the Theis Recovery analysts of well S-1 constant rate test recovery data are 3 93 mlday and 12 9 m2/day This hydraulic conductivity is consistent with fine-grained sand (Todd, 1980) Mass Removal A total of 6,455 gallons of groundwater was extracted from S-1 and S-1-85 over the duration of this mass removal event Table 4 presents the pump test extraction data, analytical results of groundwater samples, and mass removal data The chemical analytical data collected during pumping were used to determine the mass of TPHg, benzene, MTBE, and 1,2- DCA removed during this event At the end of pumping, a total of 0 001 pound of MTBE, 188 pounds of TPHg,0 103 pounds of benzene, and 0 019 pounds of 1,2-DCA were removed SITE CONCEPTUAL MODEL UPDATE The data collected during this investigation did not significantly change the site conceptual model (SCM) for this site other than the finding that a former service station was present on the property north of the subject site This fact could affect the SCM if this former site is found to have had a historical release We have proposed assessment work on the property where the former service station was located The property owner has denied us access to the property The CPT investigation did not identified any other laterally continuous coarse-grained zone deeper than the one occurring at approximately 110 fbg The updated SCM is presented in Appendix J CONCLUSIONS Records Research Cambria's records research determined a former service station was present on the property north of the subject site Based on the fact that a service station was located north of the Shell site and that the predominant shallow groundwater flow direction is toward the southeast, it is possible that a release from this former service station may be contributing to groundwater impact in the vicinity of both sites Cambria has proposed work to investigate this former service station, but we have been denied access to the property to perform the investigation SJCEHD staff has offered to help discuss our property access request with the property owner 0797 10