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water will drain down through the fractures to the voids created by the mine. The greatest potential effect on ground water is for perched aquifers in the Vermejo and the overlying Raton Formations to be dewatered by subsidence. Wells which use these perched aquifers could experience drawdown effects. However, due to the low hydraulic conductivity of the aquifers, the fact that the aquifers in this area tend to be laterally discontinuous, and the effects of past surface and underground mining, ground water impacts (both magnitude and extent) are difficult to predict. The operator is obligated to comply with Rule 4.05.15 pertaining to water rights and replacement if an owner is injured as the result of the operation. The ground water monitoring plan has been designed to identify ground water impacts before they extend to water supply wells. These measures will ensure a better understanding of the impacts to the ground water system and protection of water resources in the future. The existence of the mine workings will permanently modify the pattern of ground water flow. The flooded mine constitutes a region of essentially infinite permeability that will tend to cause ground water to preferentially pass through the workings. The water passing through the flooded mine may be degraded in quality, relative to that in the undisturbed strata. Another potential ground water impact is due to subsidence and the fracture-related drainage of the surface water bodies into the subsided areas. These surface water bodies would be the mine water ponds, ephemeral drainages, and the perennial Newlin Creek. Dewatering of the ponds would short-circuit the water system during mining, which is not considered a significant impact. Also, the effects to ephemeral drainages would be minimal. However, diversion of stream flow from Newlin Creek to the underground workings may be significant. The interception of surface water or shallow ground water by underground workings presents a potential impact to water availability in Newlin Creek. However, as previously mentioned, Newlin Creek's surface flow is diverted upstream via a pipeline owned and operated by the City of Florence. This reduces the significance of any depletion of the creek due to the mine. The mine is presently incurring water sources in both the north and south sections of the mine. Quantification of total depletions to Newlin Creek are nearly impossible to make, since mining adjacent to this creek was primarily conducted from 1900 through the 1970's. Most of these areas have been sealed off and, therefore, could not indicate reliable inflows. However, the mine inflow study being conducted by the operator will provide valuable data on impacts from the Southfield operation. The primary source of water entering the mine appears to be abandoned workings nearby and above the 35