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(Page 2) MINE ID # OR PROSPECTING ID # M-77-319 INSPECTION DATE O1/11/95 INSPECTOR'S INITIALS RCO OBSERVATIONS This inspection was scheduled by the Division as a follow up to a previous inspection (dated 9/15/94) from which several questions arose about the permitted operation. The operator was contacted about the inspection, but ground conditions did not allow access to the site. The following items were discussed with the operator at the office and processing plant offsite. The prior problem of no record of a Stormwater Management Plan has been abated. Written contact was received by the Division on 11/28/94, noting the SWMP permit number (COG 500746) . The actual areas of activity under this permit, compared with inactive portions of the permit area, and compared to adjacent pre-law disturbance outside the permit, were clarified. The west pit is the one actively mined under this permit, though the east one is also in the permit area. The operator stated that the east pit and its separate access road have not been disturbed since the permit was issued. This matches the observations made during the last inspection. The active west pit is to be minimally reclaimed, according to the approved plan in the files, and according to the operator's statements. The pit is to be left open, and highwalls not reduced. The pit floor will be shaped to provide positive drainage from the pit. The majority of earthwork will be to push material against the toe of the highwalle, creating 2:1 or gentler slopes. The piles of topsoil and overburden adjacent to the pit on the north side will be used for this backfilling and to cover the regraded portions of the pit. The west pit floor is generally on one level, except for a small area at the east end, which is about 15 feet higher. The pit receives drainage from non-pit areas within the permit area. There has been some erosion across the step between these levels, though no material appears to be moving beyond the foot of the step. Reclamation should address stability of this feature too, possibly by directing all drainage into one or two channels, making the step gentler, and placing riprap in the new channels. Riprap material might be obtained from the area of large rocks immediately east of the west pit, in the permit area. The west end, where all drainage from the west pit ultimately goes, has a well established sediment pond existing. It is not known if it has sufficient capacity for controlling the runoff from a 10-year, 24-hour event. The operator should provide measurements of this structure to the Division, for use in determining its sufficiency or possible need for more capacity. This will also be necessary for calculating a bond amount. Relevant information should include length, width and depth, plus any notes about a spillway apron or culvert. The access road into the pit is a short spur off an existing ranch road. The ranch road will remain after reclamation. Revegetation is to be from seeding grass and forb species, and planting of seedling trees and shrubs. The operator stated that seedling planting has been tried numerous times, but with little success due to several factors. However, natural tree and shrub regeneration has been good on the site. It appears that, overall, the required average number of trees per acre has been met. Successful seeding will be best accomplished by conscientious handling and distribution of available topsoil. Though the perlite makes a good growing medium, its white color prevents a significant .degree of grass and forb growth. More surface covered with topsoil will result in better revegetation. This was discussed because of the bond and because operator stated that reclamation may start in the next few years. When revised bond figures are calculated, they will sent to the operator for review. I & E Contact Address cc: Jim Stevens/DMG ❑ CE NAME Ethel M Steiner ❑ BL OPERATOR Persolite Products Inc ❑ FS STREET P O Box 105 ❑ HW CITY/STATE/ZIP Florence CO 81226 ❑ HMWMD (CH) ❑ SE ❑ WQCD (CH) ❑ OTHER