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September 15, 2010 C-1984-067/Coal Gulch Mine TAK <br />topography, blends well with surrounding undisturbed lands. No open drillholes have been found on the site <br />during the current or past inspections. <br />HYDROLOGIC BALANCE -Rule 4.05 <br />Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, 4.05.10; <br />Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water Monitoring 4.05.13; Surface Water Monitoring 4.05.13; <br />Drainage - Acid and Toxic Materials 4.05.8; Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: <br />The upper pond is a depression on the ground surface that holds water a few feet deep during wet periods. <br />It was dry during this inspection. The lower pond receives runoff from much of the former surface facilities area <br />and a seep from the backfilled portal of a pre-law mine. The seep was dry during this inspection and the llower <br />pond was dry. <br />As mentioned in past inspection reports, the remnants of the inlet end of the primary spillway culvert of the lower <br />pond remain on the inslope of the pond's embankment. An opening on the outslope of the embankment <br />approximately one foot in diameter may be the outlet end of the culvert. Since the last inspection in May 2010, an <br />unknown party (perhaps the landowner) has constructed a gravel road into the site from the highway. The road <br />crosses over what was part of the emergency spillway for the lower pond, reducing the spillway capacity. The <br />pond embankment appeared erosionally and structurally sound. <br />With the exception of the two ponds, positive drainage exists throughout the site. The clear water diversion ditch <br />remains on the western side of the site, and conveys runoff past the site that comes from upstream of the site. An <br />earthen ditch near center of the site would convey runoff to the lower pond. <br />RECLAMATION SUCCESS - Rule 4.15, Rule 3: <br />The following characteristics of the Coal Gulch site that were observed during this inspection support a <br />finding to approve final surety release and termination of DRMS jurisdiction: topography that blends with the <br />surrounding topography, positive site drainage, vegetation that locally provides long-term erosional stability and <br />that supports a postmining land use of wildlife habitat. <br />REVEGETATION - Rule 4.15 Vegetative Cover; Timing: <br />Much of the central part of the site has sparse grass cover. The southwest part of the site that is being used <br />for storage has areas of bare ground due to vehicle traffic. Wheatgrasses, pennycress, mullein, and field bindweed <br />cover the site in varying degrees. The site could benefit from thistle spraying. Areas where grasses are more <br />developed would provide long-term erosional stability. <br />SLIDES and DAMAGE - Rule 4.12: <br />No slope stability problems or new erosion were evident. Overall the site is erosionally stable. In past <br />years a sediment fan has been deposited near the center of the site apparently from runoff from the steep slope on <br />the eastern side of the site that extends up to the adjoining Arness-McGriffin site. The fan does not hinder use of <br />the site. <br />Number of Partial Inspection this Fiscal Year: 1 <br />Number of Complete Inspections this Fiscal Year: 0 <br />Page 3 of 6