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y, h a' for chemical analyses. Soil samples were also submitted to Nelson Laboratories, Stocktc, for grain size analyses. 4 . 1 .2 Lha, S`e�II During Phase II, monitor well installation techniques were modified from those previously used, A 3-53 Auger rig was used to drill two 7-inch diameter boreholes, each completed through an approximate depth of 55 feet. Soil samples were collected at 5 ft intervals, beginning at 5 feet, using a hollow stem auger. Upon retrieval, soil samples were described by an ESE field geologis,,, for lithology and color. Prior to sample submission for chemical and physical analyses, soil samples were screened with a photoionization detector (PID) to determine the presence of volatile organic compounds ("QCs) . The PID was calibrated as per manufacturers directions, but provided no evidence of strata warranting additional laboratory analyses. Subsamples were therefore �. submitted fpr - laboratory analyses only for those collected at both 3.0 and 35 feet, based on recommendations of the ESE field geologist, general concordance with Anheuser-Busch 's field representative, and interpretation of County Health 1 requirements.quirements. Soil samples were iced, and delivered to the :Laboratory within 24 hours of sample collection. Each borehole was completed as a 2-inch diameter ground Nater monitor well, as shown previously ill Figure 4-2, and described in Table 4-1 . Decisions to screen discrete intervals were '.used primarily County Health's requirement to screen approximately 24 feet of the upper saturated zone and provide some additional screening to account for possible groundwater fluctuations. Unlike during Phase I, PID readings were all close to ambient levels, and provided little input. in the decision making process. 4-6