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six inches above the top of slot Two feet of hydrated bentonite will then be used above the sand as a sanitary seal Neat cement with less than 5% bentonite will be placed on top of the bentonite seal to surface, where surface security will be provided by the placement of a 6 inch diameter by 12 inch deep traffic rated water tight traffic box secured with concrete shoulder, see Figure 2 for well construction details A locking thermos type well cap will be placed at the casing top to secure the piezometer The B zone piezometers will be drilled approximately 3 feet west of the A zone piezometers and noted as PZIB and PZ2B respectively Drilling will be as described above, with drillinglcoring to the 27 foot depth Core examination will determine the proper placement of the 5 foot length of 2 inch diameter, 0 02 inch slotted PVC screen Piezometer construction will be similar to that discnbed above except#3 sand will be used, see Figure 2 for well construction details The piezometers will be developed by surge and block method, three days after they have been installed The pump test(Stage 2) will be started at least one week after development of the wells Destruction of well MWI, will be by over-drill, using 8 inch hollow stem augers to 34 feet below surface, original boring was 8 inch to 33 feet below surface The overdnlled boring will then be backfilled with bentonite pellets as the augers are staged out of the hole Once the boring has been backfilled to within 4 feet of surface with bentonite pellets, the bentonite will be hydrated and the remaining boring will be backfilled with clean soil to surface All solid and sludge material produced by the drilling of the piezometers and the destruction of MW I will be placed on and covered with 6 incl black plastic and left on site for future transfer to the proposed excavation stockpile at a later date All fluids produced by the drilling of the piezometers and the destruction of MW1 will be placed into 55 gallon DOT 17H drums and secured onsite for later disposal Stage 2 - Baseline Information Baseline information will be collected from the two water bearing zones one week prior to any pumping Transducer/data loggers will be placed into wells MW I, RWIA and RWIB one week prior to any pumping to measure the fluctuations of the potentiometric heads of these wells Depth to water measurements will be obtained from all wells associated with this site prior to placement of the transducer/data loggers, see Appendix A- Revised Pump Test Plan, Plan For Pump Test for more detail Stage 3 - Step Draw Down well RWIA Transducer/data loggers will be placed into newly installed piezometers PZ 1 A, PZ I B, PZ2A and PZ2B and into wells MW 1, RW 1 A and RW I B Depth to water measurements will be obtained from all wells prior to placement of the transducer/data loggers Once the transducer/data loggers are in place a step draw down test will be performed on well RWIA Using a variable speed Grundfos pump in RWIA, pump rates will be increased in steps at 1 gpm increments Depth to water will be measured at wells that do not contain the transducer/data loggers periodically, recording the time and the depth to water measurements Once the draw down reaches equilibrium, the pump rate will be increased in I gpm increments This test is expected to last 8 hours Once this test stage is finished, the site will be i 3 Sanchez ADD PT 10-2002