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-2- <br />~ are down dip and have not been producing any water. The single sedi- <br />ment pond on the property for Bear „3 will be designed to contain any <br />runoff from the mine property fcr a 10-year, 24-hour event. This pond <br />will be properly lined to prevent infiltration into the alluvium of <br />the North Fork of the Gunnison river since it is contained within the <br />North Fork alluvium channel. From careful analysis and examination of <br />available date it is reasonable to assume existing ground and surface <br />water will not be ad•aersely affected. The state has detersnir.ed that <br />an alluvial valley floor (AVF) occurs about 1 mile on the North Fork <br />of the Gunnison. Using the same conclusions as derived above, a neg- <br />ligible effect on this AVF is expected. <br />c) The Bear ~3 dine surface area over the coal lease is rugged, irregu- <br />lar, sloping towards the north, and adjacent to the south cliff area <br />of the Worth Fork of the Gunnison river valley. Topographic maps in- <br />dicate this is a very poor catchment area for surface water due to the <br />topography, lack of an established basin, lack of moisture, and to- <br />pography conducive to rapid runoff. The surface area contains no <br />perennial streams and only intermittent or ephemeral channels that <br />produce water only as a direct result of precipitation. Water infil- <br />tration is subsequently very low. Since the proposed Bear =3 mine is <br />dry, no apparent hydrologic connection is evident from the overlying <br />strata and little is expected because of the above conclusions. Even <br />in the presently being abandoned Bear ~1 mine that is presently being <br />permanently closed (1/4 mile up stream, with the same seam and same <br />side of valley as Bear ~3) where pillars have been extracted causing <br />upward caving into the overlying strata, little any water has been <br />produced. Also negligible surface subsidence effects are expected <br />because of the massive sandstone barriers (See MMS concurrence) that _ <br />might interrupt surface flows. The sandstone barriers will also limit " <br />the impact to any overlying coal seams that may have aquifer charac- <br />teristics. <br />This assessment and past-mining history in the area demonstrates that the <br />Bear ~3 mine will have an insignificant effect on the hydrologic regime <br />in the permit area and even less impact on the cumulative probable hydro- <br />logic balance of all coal mining in the area. The operations proposed <br />under the application have been designed to prevent damage to the hydro- <br />logic balance in associated off-site areas (see Sec. IX, p. 19 of the <br />Technical Analysis [TA], Proposed Decision and Findings Document, <br />4. OS14 has verified the following findings with the applicable Federal <br />and local agencies and their planning and records tin the area of the <br />mine show the proposed permit area: <br />(a) Plot included within an area designated unsuitable for surface <br />coal mining operations. (see Section XXV, p. 33 of TA [2.07.6(2)(d)(i)]), <br />(b) Plot within an area under study for designating lands unsuitable <br />for surface coal mining operations (see p. 2 of BLM concurrence letter) (see <br />~ XXV, p. 63 of TA, [2.07.6(2)(d)(ii)], [786.19(d)(2}]. <br />