2014-07-28_PERMIT FILE - P2014014 (2)

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Item No. 6.H. Describe the equipment used for the prospecting operations (CONFIDENTIAL) Item No. 6.J. Describe anticipated relationship to surface water and groundwater (proximity to streams, penetration of groundwater aquifers) No perennial surface water has been identified on or adjacent to the NSHI 160-acre RD&D Lease area; therefore, there is no nearby surface water to contaminate. During the construction phase, surface disturbance, including cuts, fills, and grading, could increase the potential for sedimentation in nearby ephemeral drainages. Streams that drain through the lease area are intermittent and usually have less than two square miles of drainage area above the project site. A sedimentation pond and runoff diversion ditches will be placed at strategic locations to minimize runoff and sediment contributions from construction areas pursuant to the construction phase SWMP. Groundwater is expected to be encountered in the Perched (where it exists), A-Groove, B-Groove, and Dissolution Surface Aquifers. See Figure 7 for a location map and cross section (confidential) indicating the vertical limits of all groundwater. However, no groundwater is anticipated to be encountered near or within the production zone because the initial OSR chamber is between the depths of 2,830 and 2,870 feet. It is unlikely that existing groundwater would be adversely affected by development operations. Approximately 942 feet of dry, confining interval exists between the top of the initial OSR and the lowermost groundwater occurrence, which is the Dissolution Surface Aquifer which is not an Underground Source of Drinking Water(USDW). NSHI may elect to research the effect of varied OSR chambers within the same well. In the case of stacked OSR chambers, the uppermost interval would be located below the base of the Lower Salt (2,284 feet below ground surface). The halitic/nahcolitic Lower Salt is approximately 100 feet thick and a very effective aquiclude. Should OSR chambers be placed near the base of the Lower Salt, approximately 462 feet of dry, competent formation would exist between the top of the OSR and the base of the USDW-exempt Dissolution Surface Aquifer. Approximately 740 feet of formation would exist between the OSR and the base of the B-Groove Aquifer. In addition, to preclude any contamination, OSR wells will be cased and cemented from below the base of the dry Lower Salt stratigraphic sequence to ground level. The initial OSR chamber will be the lowermost interval explored. The base of the Parachute Creek Member is approximately 50 feet below the bottom of the OSR and deepest planned development. This formation is dry and competent. The Garden Gulch Member of the Green River Formation underlies the Parachute Creek Member and the Saline Zone. The Garden Gulch Member consists of dry clay-rich oil shales and claystones. In the vicinity of the lease area, the Garden Gulch Member is approximately 400 to 500 feet thick. Contamination of the groundwater aquifer systems is not anticipated as any production chambers will be located and encased deep within the Saline Zone. Existing up-gradient and down-gradient NSI monitoring wells and the proximal DS-6 down-gradient monitoring well (to be constructed by NSHI) will monitor the aquifer systems quarterly. Appropriate corrective action will take place if a problem is identified. Saline liquids produced by the drilling operations with conductivity values greater than 5,000 micromhos per centimeter will be removed and placed in the existing NSI lined evaporation/process ponds near the NSI plant site. The ponds, which contain high TDS water, have a dual liner system that incorporates a drain blanket with a leakage detection system. Consequently, impacts to groundwater quality from the evaporation/process ponds are not expected. Daub&Associates, Inc. Page 11 of 17 NSHI RD&D DRMS NOI 2014