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