Laserfiche WebLink
Inventory collected in July 1986 (Volume 9A). The postmining calculation uses vegetation <br />cover data for the disturbed area collected in 2013. A primary cause of soil loss is transport of <br />solids in suspension; therefore, the comparison indicates the untreated drainage currently does <br />not yield more suspended solids than prior to mining. For the bond release parcels in SL -05, <br />BRL calculated an adjacent area -West Mine sediment yield rate of 2.48 tons per acre per year <br />and a post -mining rate of 0.96 tons per acre per year and an adjacent area -Run -of -Mine sediment <br />yield rate of 1.18 tons per acre per year and a post -mining rate of 0.41 tons per acre per year. <br />The considerable difference between these two calculated rates indicates the post -mining rate is <br />significantly less than the pre -mining rate. This conclusion is only valid if BRL used reasonable <br />variables in the USLE calculations. The Division finds that the variables used in the calculations <br />are reasonable for making the comparison; as such, the comparison appears technically valid. <br />Observations made during the bond release inspection, as well as observations made during <br />previous inspections, indicated that the vegetation on the reclaimed slopes had stabilized the soil. <br />There was no major erosional instability observed. The Division's field observations appeared to <br />corroborate BRL's hydrologic modeling results of post -mining sediment yields being less than <br />pre -mining yields. <br />Based on BRL's USLE modeling using baseline data, the Division finds that the lands proposed <br />for Phase II bond release are not contributing suspended solids to streamflow or runoff outside <br />the permit area in excess of pre -mining levels. <br />Summary and Conclusions <br />Based upon a review of the mine permit, the applicant's bond release application, and site <br />inspections, the Division finds that Bowie Resources, LLC has replaced topsoil in accordance with <br />the approved reclamation plan. Bowie Resources, LLC has established vegetation which supports <br />the approved post mine land use and meets the approved success standards for vegetative cover. <br />The Division finds that the reclaimed area subject to this bond release is not contributing suspended <br />solids to streamflow or runoff outside the permit area in excess of pre -mining levels or in excess of <br />adjacent non -mined areas. <br />IV. PROPOSED DECISION <br />Based on the observations above, the Division proposes to Approve Bowie Resources, LLC's <br />request for a Phase I and 11 bond release for the Bowie No. 1 Mine. This proposed decision will <br />release the applicant from 1.0 acres of Phase I liability for backfilling, grading, and drainage <br />reestablishment associated with the West Mine Fan Site. This Proposed Decision will also release <br />the applicant from 23.3 acres of Phase II liability for topsoil redistribution and establishment of <br />vegetative cover. The 23.3 acres is composed of 13.1 acres associated with the West Mine and 10.2 <br />acres associated with the Run of Mine (Timber Storage Area) area. <br />When determining the amount to be released under a bond release request, the Division is required <br />to limit the release amounts to the percentages allowed under Rule 3.03.1(2), and ensure that the <br />release amount does not result in the Division holding less bond than would be required to complete <br />