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Disposable plastic bailee s were used to collect water samples after the wells had been purged Thiee 40-m1 EPA vials were collected from each well and transmitted in a chilled container to Zymax Envirotechnology in Shell Beach, California ' 3.4 Soil and Groundwater Analysis Soil and water samples were analyzed for total petroleum hydrocarbons in the ' gasoline i ange (TPH-g) and benzene, toluene, ethylbenzene, and xylenes Soil samples were analyzed by EPA methods 8015m and 8020 and are reported in mg/kg, water samples were analyzed by EPA 8260 and are reported in gg/L The laboratory ' reports and chains of custody are presented in Appendices B and C ' 4.0 FINDINGS 4.1 Stratigraphy ' generalized a is Figure 3 lized strati ra $ g g phic cross section of the site, showing the main lithologic units between the surface and 47 feet BSG Slightly clayey to slightly sandy ' silt, in various shades of brown is present from the surface to a depth of approximately 18 feet Below the silt is a layer of dark-gray to greenish-gray sand that varies in grain size but is generally moderately to well sorted The lower boundary of the sand layer varies between 26 and 33 feet in depth, and is probably erosional ' Finer-grained sand or sandy silt is present beneath the sand layer This bed is bluish- gray to gi cenish-gray in color, and was wet or saturated when penetrated in, Novemliei 1992 and October 19931 This bed was sampled at 40 and 45 feet in ' monitoring wells MW-1 and MW-3, and appears to extend to at least 47 feet Silt or clayey silt is also present below 40 feet in MW-2, but an apparently thin layer of I ' coarse-grained Pebbly _sand was sampled at 45 feet The base of this layer was observed at 46 5 feet I t4.2 Field Evidence of Contamination No evidence of soil contamination was detected during drilling of monitoring well ' MW-3 Samples from MW-1 below a depth of 30 feet emitted a slight odor of I!Il hydrocarbons, and samples at 40 and 45 feet had detectable concentrations of volatile II' l orgaii)c conipounds (Appendix A) In Mw-2, hydrocarbon odors were first detected ' 'at 251 feet,,,and MD readings, indicated a range from i24 ppm to 574 ppm'' Water samplT collected�fromr MWA and MW-2 I�lso emitted (hydrocarbon odors E IJill IIF I r 'I Ir II I r 14�lr lilt I`ph�l Ili ill�l I 1 ! i„ I II ! II I I ! JI IFq If ll�� I!'�"�I r I�I'�I I I I �I��I ' 11r iIl II I - _ I _ I'I r 1 1 II i ' II 1 ,ri `k11 � Irll'�'I'I 'prll� III ill ll�I�`,�ll! I I Eh<<IIIifI I�' � � 1 ISI