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VIII. subsidence. The Division, however, found, in conjunction with the approval of this revision, that no alluvial valley floor existed in this area, that operations in this area were designed to prevent damage to the hydrologic balance outside the permit area, that the probable hydrologic consequences of the operation were minimal, and that no change was required in the cumulative hydrologic impact assessment in the original Findings. These conclusions also remain valid. Another enlargement of the permit area during the first permit term included three railroad loadouts in the City of Trinidad. These are located in close proximity to the Purgatoire River, but not directly on the accompanying alluvial valley floor. The total areal extent of these loadouts is quite small; their impact on the quantity or quality of surface and ground water in this area is insignificant as described in Sections V and VI of this document. They will have no adverse impact on the alluvial valley floor occupied by the Purgatoire River. The present and proposed operations are in compliance with the requirements of this section. Water Rights and Replacement - Rules 2.04.7(3), 2.05.6(3)(a)(ii). n nn ein.i_~ __~ ~ nr •r The operator has committed to replace the ground water supply of any established user whose supply might be disrupted or contaminated by the mining operation and has satisfied Stipulation No. 4 of the original Findings. There are no established surface water users whose supplies would he impacted by the mining. The present and proposed operations are in compliance with the requirements of this section. IX. Probable rologic Conse and Cumulative Im Probable Hydrologic Consequences is Assessment - In the original Findings document, the Division concluded that the probable hydrologic consequences of the Animas mining operation would be minimal. The results of surface and ground water monitoring at the mine site during the first permit term have confirmed this assessment. There have, however, been some changes in the operations plan and the size of the permit area since the Animas Mine permit was approved. Following the cessation of active operations in mid-1964, water from the Animas and "storage" mines has been pumped to the surface and conveyed through the existing sediment and surface water control system to the sediment pond. This outflow averaged over 13,000 gallons/day during the 1985-1986 monitoring year. Water from the Helen Mine, on the other hand, was directed to a surface sump from which it evaporated. Excess mine water was not considered in the original permit application and is largely due to the inactive status of the mines; under active mining conditions water flowing into the mines would have been put to use in surface and underground dust suppression. -15-