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BTEX and TPHG, utilizing EPA methods 8020 and 8015, respectively. The laboratory did not detect any BTEX and TPHG at or above method detection limas in ether sample Soil sampling results are summarized in Table 1 Laboratory data sheets and chain-of-custody documentation are included in Appendix III 3.2.2 Monitoring Well Construction Soil borings MW2 and MW3 were subsequently completed as groundwater monitoring wells to further assess the extent of groundwater contamination beneath the site, and to provide measurement points for the determination of groundwater flow direction and hydraulic gradient. Each well was constructed with 2-inch PVC casing The screened interval of each well was positioned from approximately 5 feet above to 15 feet below the encountered water table to allow for seasonal water level fluctuations A well screen slot size of 0.01 inch was used The boring for the monitonng well was advanced with 8-inch outside diameter hollow ' stem augers When the augers were advanced to the desired depth of the well, the well casing was lowered down the center of the augers and set to the appropriate depth The ' annular space between the augers and the screened portion of the well was backfilled with Lonestar #2-12 sand As the filter pack was placed, the augers were withdrawn from the borehole so the sand flowed from the augers into the annular space of the borehole. The filter pack was extended to approximately two feet above the top of the screened portion of the casing A two foot seal of bentonite clay was placed in the ' annular space above the filter pack Since the bentonite seal was positioned above the water table, five gallons of potable water was added to allow the bentonite to gel. The ' remaining annular space was backfilled to the surface with neat cement using the tremmie method R-060092 TX