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~ i designed, constructed, tested, and certified to assure containment of the solutions in accordance with the terms of the reclamation permit and the Rules. The ground and surface water monitoring plans and mining system monitoring plans are designed for early detection of leaks from the mining cavities, the solution mining wells and the surface piping. DMG has required submittal of analyses of process solution chemistry that will be used to assure adequate design of Environmental Protection Facilities. The chemistry of the process solution is held as confidential information under Rule 1.3. Comment #15: American Soda should provide site-specific studies that support the subsidence scenario contained in the reclamation permit application and the studies should be made available for public comment before a reclamation permit is considered. DMG Response: DMG employs a practical approach to regulating subsidence, which stresses monitoring verification of predicted subsidence phenomena and requires mitigating measures to be implemented if subsidence in excess of predicted levels occurs or if the potential for material damage is indicated. The applicant has provided a thorough evaluation of the potential for subsidence at the solution mining site and has committed to a surface and subsurface monitoring plan and triggering criteria for specific corrective measures in [he event significant subsidence is detected. Not all of the subsidence prediction work can be released to the public because it is necessarily based on the thickness of the ore body and overburden, which is information that may be held confidential under Rule 1.3. The applicant has taken a conservative approach to initial solution mining that will provide a high degree of assurance that subsidence that may result in material damage will not occur. The first pass of solution mining through the mine panels will be on a 600 foot well spacing (with an exception as described in the permit application to provide sufficient solution for plant start-up). The final spacing of wells on 300- foot centers will occur in a second pass. This will allow for evaluation of subsidence predictions while there are still very substantial pillars in place between solution mining cavities. Comment #16: There are numerous rich oil shale horizons in the solution mining intervals, directly above the proposed solution mining horizons, within the leached zone, and above the Mahogany zone that have been overlooked and not considered for protection of future mineability. DIVIG Response: The most important stratum to be protected from material subsidence damage is clearly the Mahogany zone. It contains the richest oil shale deposits and also serves as a leaky aquitard between the upper and lower aquifers. The subsidence monitoring and corrective action plan provides specific protections to the Mahogany zone. If the Mahogany zone is protected from subsidence damage, then the strata vertically above it will also be protected. The leached zone is already rubblized by natural leaching and removal of evaporites. The subsidence action plan requires lowering the solution mining interval if significant subsidence is detected between the mining interval and the dissolution surface. It is difficult to establish what effect solution mining of nahcolite will have on the future mining of oil shale in the solution mining interval. What is clear is that under any currently feasible scenarios, mining of oil shale in the saline zone would post-date mining in the Mahogany zone, which is an enormous resource, and that any consideration of oil shale mining in the saline zone is decades away. To preclude mining of