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phases as disturbance increased within the watershed. The final (Phase V) design <br />involved a 1.5 foot extension of the principal spillway riser, and elimination of a <br />"pre - settling basin" in the "B" Pit. Phase V spillway modification was completed <br />in August 2003 prior to "B" Pit backfilling. Phase V "As- Built" Certification was <br />completed in March 2004 and was included in TR -48. <br />Pond 009, a temporary sediment pond, treats runoff from the smaller disturbed area <br />which drains to Sage Creek, roughly a 439 acre watershed. Construction of the <br />pond was completed in 1991. <br />Pond 015 was constructed during the summer of 1999 in preparation for <br />development in the Seneca II -W south extension area. The pond treats runoff from <br />a 407 acre watershed that drains into Sage Creek of which only 29.5 acres were <br />disturbed by mining activities. <br />Pond 016 was constructed in the summer of 2000 in the Seneca II -W south extension <br />area. The pond treats runoff from 382.2 total acres. Discharge from this pond goes <br />into an unnamed tributary of Hubberson Gulch. <br />Pond 017, constructed in the fall of 2002, treats runoff from a 955 acre watershed <br />including mine disturbance areas from the southern portion of the south extension of <br />the permit area. The pond is located on upper Hubberson Gulch near the southwest <br />corner of the south extension area. Pond 017 construction certification and "As- <br />Built" designs were included in PR -4 submittal materials. <br />Several of the sedimentation ponds have been proposed as permanent <br />impoundments, and the impoundments would appear to be warranted to facilitate <br />postmine livestock grazing and wildlife use. However, documentation required by <br />Rule 4.05.9(13) has not been provided to allow for approval of any sedimentation <br />ponds as permanent impoundments. The following commitment is included in <br />Permit Tab 13, page 5, regarding permanent impoundment demonstration of <br />compliance: <br />Permanent impoundments will be reevaluated prior to bond release and <br />remedial construction performed to satisfy the appropriate sections of the <br />regulations. Prior to submittal of a bond release request, SCC will submit a <br />complete technical revision demonstrating that each permanent impoundment <br />meets the requirements of 4.05.9(13). <br />D. Acid - forming and Toxic - forming Spoil <br />The applicant has submitted detailed analysis of the geochemical characteristics of <br />the overburden and interburden found in the Seneca II -W Mine permit area. Initial <br />drilling and geochemical sampling was conducted within the baseline study area <br />Seneca II -W Findings Document 22 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />