GENERAL51479 - Laserfiche WebLink

Home Browse Search

-56- The backfilling and grading plan proposed by the applicant does not address the elimination of all highwalls and depressions, and reconstruction of stream channels in accordance with Rules 4.14.1(2) and 4.05.3. There are several areas at the mine site that have highwalls, benches, or depressions as a result of past earthmoving to accommodate necessary mine facilities. Highwalls which must be backfilled can be found at the coal silo, east mine water tanks, and at the west mine fan. Benches have been created south of the office, south of the active waste pile and at the west mine facilities area. Depressions have been created by the access road embankment to the west area. The backfilling and grading plan must specifically address backfilling of these and any other highwalls on the site, and regrading of benches in order to achieve approximate original contour. Removal of road bed material in order to relieve any impoundments and depressions is discussed in Section XX of this document. There are also several small drainages tributary to the Purgatoire River that intersect the mine site from both the north and the south. The Division has assumed that these drainages are ephemeral and each encompasses a watershed less than one square mile in area. Reconstruction of these stream channels during grading operations must be specifically addressed in accordance with Rule 4.05.3. In addition, the Division cannot assess whether or not the proposed post~nining topography will meet the requirements of approximate original contour due to the lack of pre-mining topography maps and cross-sections, the large scale of the current post~nining topography map and the infrequent nature of the post-mining cross sections. The current post-mining cross sections are drawn for only two areas. Of the areas of concern mentioned above, only one is depicted on one of these cross sections. The application should depict post-mining cross sections through all of the above mentioned areas of concern, at a minimum. In light of these facts the following stipulation is necessary, in accordance with Rule 4.05.3: Stipulation No. 26: THE PERMITTEE SHALL SUBMIT A REVISED BACKFILLING AND GRADING PLAN THAT SPECIFICALLY ADDRESSES THE ELIMINATION OF ALL HIGHWALLS AND DEPRESSIONS, AND THE BACKFILLING AND GRADING OF ALL CUT SLOPES AND BENCHES AT THE ALLEN MINE. IN ADDITION, THIS PLAN SHOULD ADDRESS THE RECONSTRUCTION OF THE MANY STREAM CHANNELS TRAVERSING THE SITE. A REVISED CONTOUR MAP, USING CONTOUR INTERVALS OF TEN FEET, AND ADDITIONAL CROSS SECTIONS DEPICTING THE POST-MINING TOPOGRAPHY SHOULD BE SUBMITTED. THE POST-MINING CROSS SECTIONS SHOULD ALSO IWDICATE PRE-MINING TOPOGRAPHY, IF AVAILABLE, AND EXISTING TOPOGRAPHY. THIS REVISION TO THE PERMIT SHOULD BE SUBMITTED FOR DIVISION APPROVAL WITHIN 120 DAYS OF PERMIT ISSUANCE.