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The existence of the mine workings will permanently modify the <br /> pattern of ground water flow. The flooded mine constitutes a <br /> region of essentially infinite permeability that will tend to <br /> cause ground water to preferentially pass through the <br /> workings . The water passing through the flooded mine may be <br /> degraded in quality, relative to that in the undisturbed <br /> strata. <br /> Another potential ground water impact is due to subsidence and <br /> the fracture-related drainage of surface water bodies into the <br /> subsided areas . These surface water bodies would be the mine <br /> water ponds, ephemeral drainages, and the perennial Newlin <br /> Creek. Dewatering of the ponds would short-circuit the water <br /> system during mining, which is not considered a significant <br /> impact . Also, the effects to ephemeral drainages would be <br /> minimal . However, diversion of stream flow from Newlin Creek <br /> to the underground workings may be significant . The <br /> interception of surface water or shallow ground water by <br /> underground workings presents a potential impact to water <br /> availability in Newlin Creek. However, as previously <br /> mentioned, Newlin Creek' s surface flow is diverted upstream <br /> via a pipeline owned and operated by the City of Florence . <br /> This reduces the significance of any depletion of the creek <br /> from mining. <br /> The mine is presently incurring water sources in both the <br /> north and south sections of the mine. Quantification of total <br /> depletions to Newlin Creek are nearly impossible to make, <br /> since mining adjacent to this creek was primarily conducted <br /> from 1900 through the 1970 ' s . Most of these areas have been <br /> sealed off and, therefore, could not indicate reliable <br /> inflows . However, the mine inflow study being conducted by <br /> the operator will provide valuable data on impacts from the <br /> Southfield operation. The primary source of water entering <br /> the mine appears to be abandoned workings nearby and above the <br /> mine. Quantities of mine inflows have decreased from around <br /> 40 acre-feet in 1995-1997 , to 10-15 acre-feet in 1998-2000 . <br /> According to the EFCI, this decrease is most likely due to the <br /> mine reaching an equilibrium with the surrounding groundwater <br /> system such that water no longer rises into the accessible <br /> area of the mine. <br /> Southfield Mine Permit Renewal 03 <br /> 43 <br />