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Appendix A FIELD ACTIVITIES PLAN Field activities at the McCormick and Baxter site will in- volve the collection of soil samples , the drilling and in- stallation of new monitoring wells, the collection of water samples from existing and new monitoring wells, and the col- lection of water samples from discharging pipes to the SRWCF. This appendix presents the procedures to be followed while performing the field activities such as: methods for obtaining field measurements and methods for sample han- dling, packaging, shipping, and documentation. WELL INSTALLATION Several locations have been identified for the installation of new monitoring wells. The procedures to be followed while drilling the borehole and constructing and developing the wells will be as described in the following paragraphs. DRILLING, SAMPLING, AND LOGGING The new monitoring wells will be drilled using the mud ro- tary drilling method. The bit size will be 14 inches in _ outside diameter (OD) . The mud used during drilling will be a bentonite mud. The mud density and viscosity will be maintained within appropriate limits established by the drilling industry. Grab samples of the formations through which drilling is progressing will be taken from the drill cuttings at 5-foot intervals for the purpose of lithologic logging. Sieve analyses will be performed on samples from the intervals (s) to be screened in the monitoring wells. Lithologic logs will be evaluated with the geophysical logs for each location. WELL COMPLETION, DEVELOPMENT, AND PUMP INSTALLATION A general well construction diagram for the monitoring wells is shown in Figure A-1 . The well screen and filter pack- size will be determined from the results of sieve analyses of cuttings from the zone to be screened. Well screen lengths will be selected to match the thickness of the per- meable zone to be monitored. Stainless steel screen and- carbon steel casing will be used. After the well screen and casing (with centralizers) are placed in the completed bore hole, the annular space will be filled with the filter pack. The filter pack will be emplaced with a tremmie pipe to a• minimum of 5 feet above the top of the screen. The 5 feet of sand will allow for settlement of the filter pack during well development. At least 2 feet of bentonite pellets will be placed above the filter pack and allowed to hydrate for A-1