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Item#6 The use of a hollow stem auger drilling rig in the land application area for the annual soil sampling requirements is not recommended due to the soil compaction that will result. A Geoprobe drilling rig, or hand drilled borings will result in less soil compaction and a smaller borehole. We disagree that a hollow stem rig should not be used. Because of the rough terrain in the freshly-plowed application area, we believe that most light duty Geoprobe rigs will have problems getting in. If you use a heavy Geoprobe rig, it will compact the soil the same as a light duty drill rig (both will be on a 4x4 truck chassis), and it probably weighs the same as the tractor used to plow the area. Additionally, this sampling only takes place one time per year and the land application area is frequently plowed for the purpose of loosening the soil as well as aeration, moisture control, inducing microbial activity, etc.. If hand-auguring of the soil to a depth of 6 feet, it will be hard to prevent caving of the loose soil into the hole. Therefore, that approach is not a realistic option. Lastly, use of a standard drill rig allows for obtaining blow counts. However, if after review of our rationalization, the RWQCB wants to require that a Geoprobe rig still be used, we will try our best with one. Item#7 Soil borings drilled for the annual soil monitoring shall be grouted with neat cement (with up to five percent bentonite by weight)from the total depth of the boring to a depth of 1.5 feet below ground surface. The remaining borehole can be filed with native soil to allow occasional discing of the soil without damage to the farming equipment. The San Joaquin County Environmental Health Department's Well Standards, Section 13.17.7 allows the top 3 feet to be filled with native material; because the borings will be located in application areas, this more stringent requirement is necessary. We agree with the requirement. Item#8 Permits for drilling the soil borings are required by the San Joaquin County Department of Environmental Health. Although Kleinfelder did not document this requirement in the SAP, we realize it exists. 20-4587-0l.SAP/201 I L330 Page 7 of 8 Copyright 2001,Kleinfelder,Inc. May 2,2001 KLEINFELDER 2825 East Myrtle Street,Stockton,CA 95205-4794 (209)948-1345 (209)948-0621 fax