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~.. (Page 2) HINB ID f OR PROSPECTING ID f N-SZ-015 INSPECTION DATE 7/31/95 INSPECTOR'S INITIALS 8C6 OBSERVATIONS The 97 acre pit east of the WYCO Pipeline ie mined out. There are still several stockpiles of low-grade material on the floor of the pit, including one large pile just east of the WYCO pipeline that may remain ae an island in the reclaimed topography if the material cannot be marketed and loaded out in the foreseeable future. The 97 acre pit ie being dewatered by a pump at the east end. The pumped groundwater ie discharged to a ditch and eventually to St. Vrain Creek. Because of an unusually high runoff this year, the pump had bean unable to completely de-water the pit, resulting in a substantial acreage of exposed groundwater at the time of this inspection. The pit elopes of the 97 acre pit are for the moat part at or near the 3:1 elopes required in the approved reclamation plan. Primarily, only finish grading, and topsoil replacement and revegetation above the waterline, would be required. For purposes of determining reclamation costa, the Division typically considers finish grading to be a short push of 1600 cubic yards per acre, i.e., 1 acre foot per acre. It is estimated that 23 acres will require finish grading aG the 97 acre (east) pit. This estimate ie based on 10,200 linear feet of shoreline, and TOC•foot wide pit elopes, (10,200• x 100') + (43,560 eq. ft./acre) = 23.4 agree. Total earthwork volumes estimated for finish grading of the 97 acre pit would be 1600 cu. yds./acre x 23 acres = 36,800 cu. yds. Volunteer vegetation, including some large trees, ie established on the pit elopes. If areas with good volunteer vegetation (not weeds) are at a 3:1 or shallower elope, the operator wild not be required to grade or replace topsoil in these areas. The area of active gravel extraction is in the pit west of the WYCO Pipeline. There ie a culvert through the WYCO Pipeline berm that allows water from the active pit to drain into the 97 acre pit to the east, where the water ie pumped to St. Vrain Creek ae described above. The Panhandle Eastern Pipeline has been relocated to maximize extraction of gravel in the west pit. The west facing pit elope on the WYCO Pipeline berm has been graded and revegetated. The other pit elopes would require little more than finish grading at 1600 cu. yds. per acre ae estimated above. The total acreage requiring finish grading in the pit(s) west of the WYCO Pipeline is estimated to be 15 acres. This estimate is based on 6600 linear feet of shoreline and 100 foot wide pit elopes (the 6600 linear foot estimate dose not include the west outelope from the WYCO Pipeline that has already been adequately graded). Total earthwork volumes estimated for finish grading of the west pit(s) would be 1600 cu. yds./acre x 15 acres = 24,000 cu. yds. The access to the site from the I-25 frontage road ie located just north of St. Vrain Creek. There was no permit sign, ae required by Rule 3.1.12 of the Mineral Rules and Regulations, at the time of this inspection. The operator will be required to poet such a sign no later than 12/1/95. The access road continues between the pits and St. Vrain Creek, and then around the perimeter of the 97 acre pit. There ie a two way haul road across the wYCO Pipeline berm. The crusher ie located north of the 97 acre pit, and just east of the WYCO pipeline berm. The access and haul roads, and the crusher, stockpile, and facilities area will have to be ripped prior to topsoil replacement. Measurements from the permit maps indicate that there ie approximately 12,500 linear feet of.road at the Bite. An average road width of 24 feet yields approximately 7 acres of road that requires ripping. Facilities areas that require ripping are estimated at an additional 5 acres, for a total of 12 acres requiring ripping prior to topsoil replacement. There are four topsoil stockpiles located to the north of the 97 acre pit; the largee topsoil stockpile ie located near the east end of the permit area. It ie estimated that acres at the site will require topsoil replacement for revegetation. This 88 acre area was measured on the permit maps and includes the entire disturbed area depicted minus those areas that will be below the set imated static water level. The approved reclamation plan calla for the replacement of topsoil to a six inch depth oyy~,~'~~`bed areas above the water line. This results in a volume of topsoil equal tom"'-` - - '""~ Gaeed on the longest haul distance of 7000 feet from the stockpile at the northeast corner of the permit area, around the lake, to the access gate/scale house location. In terms of the acreage requiring revegetation at the site, the 88 acres estimated to require topsoil placement would be added to the acreage rrently under the topsoil stockpiles, estimated to be 5 acres, resulting in an eatimatecre area requiring revegetation. The