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June 29, 2004 <br />Coal Gulch Mine & Arness-McGriffin Mine (2 bond forfeiture sites) <br />C/O Colorado Division of Minerals and Geology (DMG) <br />1313 Sherman, Room 215 <br />Denver, CO 80203 <br />June 22, 2004 <br />EY 2004 Special focus evaluation <br />Participants: <br />Tom Kaldenbach, DMG <br />Henry Austin, Office of Surface Mining (OSM) <br />We conducted an Evaluation Year (EY) 2004 special focus evaluation at both of these <br />former underground mine sites /bond forfeitures to determine offsite impacts. These <br />disturbed & partially reclaimed areas (and the former permit areas) are contiguous to one <br />another with Arness-McGriffin being the former portal area and associated disturbance <br />highest in elevation here, and essentially southwest facing and overlooking the lower <br />Coal Gulch Mine. This evaluation was previously conducted in EY 2000 at both these <br />sites. The EY 2000 evaluation found one minor offsite impact to a land resource (surface <br />water runoff from the Arness McGriffin Mine flows downhill and directly onto the Coal <br />Gulch Mine causing minor erosion gullies and an associated sediment delta on the <br />partially reclaimed Coal Gulch disturbed areas). This EY 2004 evaluation finds that <br />essentially the same condition described above still exists; and is still causing a minor <br />offsite impact to the land resource at the Coal Gulch Mine. This EY 2004 evaluation was <br />selected by the joint DMG / OSM Oversight Team. <br />Weather conditions were hot and dry, and ground-vegetation conditions here suggest that <br />it has been dry for the past 2 to 3 weeks and probably longer. No additional reclamation <br />has been done here since our EY 200o evaluation. The Arness-McGriffin bond was <br />forfeited in 1987 ($13,750), and the Coal Gulch bond was forfeited in 1990 ($140,000). <br />Partial reclamation of these sites was accomplished during 1989-1990 (Arness) and <br />1994 (Coal Gulch). No bond monies remain at either site. <br />Acid mine drainage from apre-law portal on the Coal Gulch permit area drains through <br />the sediment pond at Coal Gulch. Limestone crushed rock has been used in the past at the <br />inlet to the sediment pond as.passive treatment for the acid water. Very little remains of <br />this limestone rock are evident now. The pond was not discharging during the inspection, <br />and the pond inslopes show evidence of iron staining. The seep directly north of the pond <br />was flowing during the evaluation. Historically, it does not appear the pond discharges <br />frequently, but it does discharge. The inlet to the highway 160 concrete culvert below the <br />pond discharge/ open spillway area is severely eroded. This area appears to have <br />worsened since 2000. The berm /diversion ditch directing runoff to the sediment pond is <br />eroded / headcut in the diversion channel at several areas, but is still functional. <br />