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Mr. Thomas Schreiner <br />August 8, 2003 <br />Page 2 of 4 <br />8. Hall-Irwin will provide the Division a copy of the relocation agreement with Duke Energy when <br />it becomes available. <br />6.4.7 EXHIBIT G -Water Information <br />14. As Forrest Leaf, P.E., noted in his Nissen Gravel Mine Aquifer Impact Analysis dated July 18, <br />2003, "The model predicts that the installation of the bentonite slurry wall will increase the <br />water levels south of the proposed wall one foot within a distance of 1,200 feet south of the <br />wall and 1 to 0.5 feet from 1,200 feet to approximately 3,000 feet south of the proposed slurry <br />wall. Whiie this increase is notable, the depth to water in this area of the alluvium is 15 to 20 <br />feet, resulting in a decrease in the depth to water to 14 to 19 feet." The groundwater will not be <br />elevated high enough to cause hydrologic communication between pesticides, herbicides, and <br />nitrates in the upper portion of the soil profile in the surrounding area. The depth of water in <br />this area is well below the crops' rooting zone where nitrates and pesticides could exist in the <br />soil. <br />15a.According to Mr. Leaf, the model predictions will remain relatively the same throughout the <br />year. Basically the model is intended to predict the relative change at any given time and the <br />same increase and decrease will result as the natural fluctuations of groundwater in the area <br />have historically occurred. <br />15b. <br />a. Attached is a representative cross-section of a typical monitoring well installation. <br />b. Hall-Irwin will send the Division a copy of the well completion reports following installation. <br />c. According to Mr. Leaf, daily sampling is unnecessary due to the fact that groundwater <br />movement in aquifers is very slow. Experience indicates weekly sampling is more than <br />adequate to detect significant changes in the local water level. Hall-lrwin will commit to <br />monitor groundwater weekly for at least 30 days upon initiation of pumping from the <br />excavated pit dewatering trench. Hall-Irwin will notify the Division within 24 hours or by the <br />next working day if there is a significant change in groundwater detected at any of the five <br />monitoring wells during the monitoring program. <br />d. Hall-Irwin will include the requested groundwater monitoring information in the Annual <br />Report for this site. <br />19. Hall-Irwin will send the Division a copy of the State Engineer's (SEO) correspondence to verify <br />the SEO has approved the temporary substitute water supply plan and issued a well permit <br />prior to exposure of groundwater. <br />