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{ y a r A S S O C I A T E S I N C LABORATORY ANALYSIS Groundwater samples from the monitoring wells were placed on ice and transported under chain- of-custody protocol to Sequoia Analytical laboratory Groundwater samples from wells MW1, MW3, and MW5 were analyzed for TPHg and total petroleum hydrocarbons as diesel (TPHd) by EPA method 8015 modified, and BTEX and methyl tertiary butyl ether (MTBE) by EPA method 8020 ANALYTICAL RESULTS The groundwater sample collected from well MW I contained benzene (247 ppb), toluene (14 1 ppb), ethylbenzene (7 12n ppb), xylenes (11 2 ppb), TPHg (932 ppb), TPHd (2,110 ppb), and MTBE (28 8 ppb) The Iaboratory reported the chromatogram patterns indicated both weathered gas and diesel are present in well MW1 along with an unidentified hydrocarbon The MTBE detected in this sample was not confirmed by laboratory EPA method 8260 Previous groundwater samples were analyzed for fuel oxygenates utilizing EPA Method 8260 and none were detected, indicating the reported MTBE concentration is most likely a false positive due to chromatogram interference This is consistent with historical analytical data obtained from this well The groundwater sample collected from well MW3 contained only TPHd (91 6 ppb) The laboratory reported the chromatogram pattern indicated an unidentified hydrocarbon (C9-C24) is present in well MW3 This is consistent with historical analytical data obtained from this well The groundwater sample from MW5 did not contain petroleum hydrocarbon constituents above laboratory method detection limits This is consistent with previous analytical data collected from this well with the exception of September 1999 when TPHd was detected at 66 ppb, marginally above the laboratory detection limit of 50 ppb Analytical results for groundwater are summarized in Table 2 Laboratory data sheets and chain of custody documentation are included as Attachment 2 FREE PRODUCT REMOVAL Free product has been monitored and removed from MW2 monthly since a passive skimmer was installed in this well on June 27, 1997 During the Fourth quarter 1999, a total of 0 09 liters of product were removed To date a total of approximately 16 89 liters of product have been removed from the skimmer placed in MW2 A summary of product volume removed and previous product analytical data is *� presented in Table 3 Field notes associated with free product removal during the reporting period are included in Attachment 2 625811QUARTLYI4QR-1999 DOC 3