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that exhibit a sufficient degree of neutralization potential. Analyses performed using lithologic quality information and ground water monitoring data have shown that replaced spoil material will have only a minimal, short term impact on ground water quality (see Probable Hydrologic Consequences at the end of this section). However, WFC has developed plans for sampling overburden during mining to identify the quantity and quality of deleterious material (see Section 2.04.6, Geology). Naturally occurring waters in the surrounding undisturbed ground water system exhibit a high degree of mineralization (see Section 2.04.7, Hydrology Description). Well yields are low. Most recharge to the local undisturbed ground water system is from both the Lower Second Park and the West Lateral irrigation ditches and associated laterals via seepage. This localized, artificial source of ground water recharge will augment slower, natural recharge contributions during the spoil resaturation process. As spoil resaturation progresses, the quality of ground water in the spoil will likely approach the water quality of surrounding geologic units. Mixing and the overall high degree of neutralization potential of the spoil material will minimize changesingroundwaterquality. See following discussion on Probable Hydrologic Consequences. Based on physical and chemical analyses performed on core samples taken from the lithologic units to be affected by mining (see Section 2.04.6, Geology Description), a classification system • has been developed for these units with regard to handling during operation and reclamation activities. A handling plan for those material classes identified by sampling as being potentially deleterious to revegetation or the ground water quality in either mining area has been developed and is presented in Section 2.05.4(2)(d), Topsoil (Redistribution). It is not anticipated that WFC will transfer ownership and use of any wells completed within New Horizon 2 mining areas. Bore holes, shafts, wells, and auger holes will be cased and/or sealed to prevent possible ground water degradation from mixing of waters of different quality within the bore holes and acid or toxic surface runoff entering the bore holes. A specific plan for sealing of bore holes, exploration holes, auger holes, wells, and shafts is presented in Section 2.05.6(3)(b)(v), Hydrologic Reclamation Plan. Ground Water Quantity Typical backfilling methods largely involve the use of dozers and trucks (see Section 2.05.4(2)(c), Backfilling and Grading). Replaced spoil materials exhibit greater porosities and hydraulic conductivities because of increased void values, regardless of how the spoil material is replaced in the pits. Spoil replacement (backfilling) using methods outlined in Section 2.05.4(2)(c), Backfilling and Grading, will ensure the eventual resaturation of the disturbed areas (pits), . (REVISED 6/01) 2.05.6(3) - 3