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-26- Perennial streams, however, may experience significant depletions of flow if mine workings are extended adjacent to and/or below the level of the stream valley (e.g., the bedrock alluvial contact). The lower stream gradient and the thicker alluvial deposits in perennial stream valleys favor flow retention and recharge to the ground water systems. Due to the increased flow retention and ground water recharge in perennial stream valleys, there is a greater potential for stream depletions by mining adjacent to or under these stream valleys. Amine in these areas could generate depletions by increasing mine inflows in the area. These mine inflows could be induced either through the mine workings encountering existing faults or fractures or strata recharged by the stream, or through the mine producing subsidence fractures which extend to the stream valley bottom or to rock strata recharged by the stream. Only one mining operation, Dorchester No. 1, will undermine a perennial drainage. The quantity of flow may be depleted in Newlin Creek through the dewatering of faults, fractures and rock strata which are in direct or indirect communication with the alluvium or stream bottom. The Dorchester No. 1 Mine has recently mined beneath Newlin Creek. Inspection of the underground workings by CMLRD personnel showed this portion of the mine to be making measurable amounts of water. At the present a quantitative estimate of depletion is not available. Future monitoring will provide data. However, since Newlin Creek is usually diverted by the town of Florence above the existing permitted mines, cummulative impacts to Newlin Creek are considered small. In summary, it is unlikely that the current and proposed mining activities, will significantly impact the natural hydrologic balance beyond background levels produced by previous mining activities except in localized areas. Because of the lack of pre-mining hydrologic data, it is difficult to quantify the magnitude of the impact that has already occurred. However, if adequate hydrologic monitoring is carried out, a better understanding of impacts due to the current and proposed mining operations will result. During the Permanent Program permitting process, all of the active mines will be required to implement adequate hydrologic monitoring programs. This will better enable the Division to make the required hydrologic regulatory decisions for future mining proposals An assessment of the probable hydrologic consequences of the proposed mining operation and an assessment of the probable cumulative impact of all anticipated mining in the general area on the hydrologic balance have been made. Pursuant to Rule 2.07.6(2)(c), the Division finds that the operation has been designed to prevent material damage to the hydrologic balance outside the proposed permit boundary. IX. Climatological/Information and Air Resources - Rul Climatological data, as given in Section 2.04.8 of Volume I, pages 97 through 121 of the application and page 19 of Volume II of the 2nd Adequacy Response, has been reviewed by the Division.