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the safety and health of MARK Group employees on site are presented in <br />Appendix C. <br />5.3 Task 3 - Develop and Sample Wells <br />Once the grout seal has set for a minimum of 72 hours but no later <br />than 96 hours, any new wells will be developed using air surging <br />techniques. A special three stage filter will be used to clean the air of <br />compressor fluid and vapors prior to entering the well. Air surging <br />development will be accomplished by lowering a 1/2-inch PVC pipe into the <br />monitoring well. The pipe is attached to a 2-inch pipe "T", which allows <br />direct evacuation of the well. The inner pipe is connected through the <br />"T", which is connected to the air compressor. The air from the compressor <br />is passed through the filter down the air line and the well is pumped by <br />the air lifting the water out of the well. The wells will be evacuated by <br />pumping the well for a brief period, and then the air is shut off to allow <br />formation water to flush the screen and filter, which forces any of the <br />loose fine-grained material into the well which in turn is air lifted out. <br />This on-off surge cycle will be continued until the discharged water is <br />relatively free of silt and other fine-grained material. <br />Prior to sampling, water levels and product thicknesses in the wells <br />will ';'be measured, and approximately 5 casing volumes of water will be <br />removed. One set of water samples (a maximum of 8) will be collected in <br />accordance with EPA and RWQCB accepted protocols and analyzed by Brown and <br />Caldwell's analytical laboratory for BTX (EPA Method 602) and organic lead. <br />5.4 Task 4 - Evaluate Field and Analytical Data <br />Once the chemical analyses are complete the distribution of elevated <br />concentrations of fuel components can be assessed. A series of overlay <br />5-4