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C A M B R I A fbg and screened at the bottom of the sand zone that occurs at this depth. If warranted, a conductor casing may be first installed through the shallow water bearing zone using mud rotary drilling equipment. The screened interval of this well will extend from approximately 75 to 85 fbg. The well will be constructed using four-inch diameter Schedule 40 PVC casing. The sandpack will be placed from the bottom of the well screen up to one foot above the top of the well screen, followed by a two-foot thick bentonite seal, and cement grout to grade. Actual well construction details will be based on field conditions during drilling. The well will be secured with a locking cap under a traffic-rated well box. © WeQ Head Survey: The longitude, latitude, and elevation of all newly installed wells will be surveyed by a licensed surveyor per the State of California Geotracker standards. Aquifer Testing. The aquifer testing is proposed at this site for two purposes: to determine the hydraulic characteristics of the subsurface sediments and to remove 1,2-DCA mass from the area of the site containing the highest concentrations. Step-discharge tests will be performed first in each well to determine a sustainable pumping rate for the constant-rate test. The constant-rate test in S-1 will be performed for a period of five days. The constant-rate test for well S-1-85 will be yz day test. The shorter duration test in well S-1-85 is proposed to minimize downward migration of the higher 1,2-DCA concentrations found in the shallow zone. The test will utilize wells S-1 and S-1-85 as extraction points. Groundwater will be extracted using an electric submersible pump. The extracted groundwater will be temporarily stored in a 20,000-gallon Baker tank. A liquid-level switch mounted in the Baker tank will be connected to the groundwater pump to prevent tank overflow. Based on the extraction rate,vacuum trucks will be scheduled to periodically remove water from the Baker tank in order to maintain storage capacity and continuous extraction. The extracted groundwater will be transported to the Martinez Refining Company in Martinez,California for recycling. Groundwater samples will be collected from well S-1 prior to extraction,each day of the constant-rate test,and at the end of pump test. Mass removal effectiveness will be evaluated by determining 1,2-DCA mass removal,the 1,2-DCA concentration trend over the course of the pump test, and the 1,2-DCA concentration trend from subsequent quarterly groundwater sampling events. Similarly,groundwater samples will be collected from S-1-85,prior to,during, and after the constant-rate test. 0797 6