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CLEARWATER <br /> G K O U P, I N C <br /> Envrrannrentai Services <br /> 2.2 Monitoring Well Installation <br /> Three of the six borings (SB-2, -4, and -6) were converted into monitoring wells (MW-1, -2, <br /> and -3, respectively) constructed of 2-inch diameter schedule 40 PVC flushed-threaded well <br /> material Twenty feet of 0 020" slot well screen extends from the bottom of each well at 26 <br /> feet bgs to 6 feet bgs A filter pack of#2/12 sand was placed in the annular space against the <br /> screen and extends from the bottom of each well to two feet above well screen The filter pack <br /> is topped by a two-foot thick bentonite seal The remaining annular space was sealed with <br /> neat grout Wells are protected at the surface by locking expansion plugs and flush mounted <br /> traffic rated well boxes Well construction details are included in Appendix B <br /> 2.3 Monitoring Well Development, Sampling and Surveying <br /> The monitoring wells were developed by alternate surging and bailing on September 29, <br /> 1997 At least ten saturated well casing volumes of water were removed Temperature, <br /> conductivity, and pH measurements of development water were collected during well purging <br /> Prior to developing, the depth to water was measured to the nearest 0 01 foot, from the top of <br /> the well casing using an electric water sounder The wells were then bailed as stated above <br /> After groundwater in the wells recovered to 80% of the pre-purged volume, a polyethylene <br /> sampling bailer was dedicated to the well and used to collect a groundwater sample Water <br /> samples were transferred to laboratory supplied sample bottles and labeled with appropriate <br /> well designations Samples were documented on a chain of custody form and placed in a <br /> cooler for shipment to AEN The samples were analyzed for TPHg, BTEX with MTBE, <br /> TPHo, and TPHd <br /> On September 29, 1997, top of casing elevations of each new well were surveyed by <br /> Clearwater, to the nearest 0 01 foot relative to a project datum Field data sheets which <br /> include gauging, development, sampling, and survey data are included in Appendix C <br /> 3 <br />