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Pond Removal Checklist <br />Pond: Ponds 1 (large) and 2 (small) <br />Mine: Carbon Junction Mine <br />Permit No.: C-92-080 <br />Technical Revision: 15 <br />Date review completed: 1/10/08 O <br />CDMG reviewer: Tom Kaldenbach <br />Requirements for removing a pond, Require- <br />Section 4.05.2(2) ment met Comment <br /> (Yes / No) <br />The Division has authorized the removal. See Removal can be authorized upon satisfaction of the following items in this checklist. <br /> comment <br /> DRMS inspections have found the disturbed areas to be vegetated. Overall the disturbed <br />The disturbed area has been revegetated and areas have appeared erosionally stable, with localized gully formation in the North Pit area. <br />stabilized. Yes The gullied areas were reconstructed to a more stable drainage configuration in November <br /> 2007. <br /> The TR-15 submittal contains USLE calculations that show soil loss rates on disturbed <br /> lands are less than the soil loss rates on adjacent, steeper undisturbed lands. Map 4-2 in the <br /> permit application shows premining topographic contours, which indicate the premining <br /> slopes of the disturbed lands were similar to the adjacent undisturbed lands. The USLE <br /> calculations in the submittal used reasonable values for R, K, P, LS, and C, compared to <br /> the original pond designs in Appendix 5-2 of the permit application (40CFR, 434.82 <br />The untreated drainage from the requires use of the same watershed model used to acquire the permit). <br />disturbed area does not contribute <br />additional suspended solids above <br />Yes <br />DRMS verified that soil loss from the disturbed lands are less than soil loss under natural <br />natural conditions. conditions, by calculating the USLE for three locations on the disturbed lands using <br /> premining slope values from Map 4-2 of the permit application and premining cover values <br /> from the baseline vegetation data in Appendix 4-6 of the permit application (see attached <br /> spreadsheet calculation and map). SEDCAD was not used for verification because it does <br /> not calculate average annual sediment yield, as required by the applicable effluent <br /> standard, 40CFR, 434.81 - 434.82.