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<br /> <br />(Page 21 <br />MINE ID # OR PROSPECTING ID # M-1984-001 <br />INSPECTION DATE 9/25/01 <br />INITIALS WHE <br />OBSERVATIONS <br />This inspection occurred in accordance with the Mined Land Reclamation Boar 's directive to staff <br />to coordinate an on-site meeting with CDOT personnel to discuss reclamati n issues addressed <br />under Technical Revision No. 1 (TR-011• Present during the inspection were obert Florez and Ty <br />Ortiz from CDOT, Linda Danberger and Mike Meininger from Mesa County, John Withers from <br />Geotechnical Engineering Group, Inc., John Kornfeld from Rhino Engineering Inc., the operator, <br />and DMG staff. Attached to this inspection report is a DMG memo from AI mundson and Jim <br />Dillie, dated 10/1 /01, detailing the geotechnical stability issues discussed dur ng the meeting and <br />subject of TR-01. TR-01 is a request to allow the highwall and 60,000 cy stoc pile of -3" material <br />to remain as permanent features. <br />The Surface Rock Pit is approved for 28 acres total affected area. The phas d reclamation plan <br />indicates that approximately 13.5 acres may be affected at any given time, The permit area is <br />divided into two locations, Areas A and B. Area A is a quarry type extraction f metamorphic and <br />igneous rock, approved for 18 acres affected area, approximately 9.5 acres ma be affected at any <br />given time. The highwall and 60,000 cy material stockpile referenced under R-01, is located at <br />Area A. Area B is a granite boulder and backfill material harvesting area, ap roved for 10 acres <br />affected area, approximately 4 acres may be affected at any given time. Per it status is active. <br />DMG holds S27,000 financial warranty. <br />Area A Public access is controlled by locked gate. Much of the loose rock, reviously observed <br />on the face of the highwall, had been removed. Reclamation grading had occ rred at the base of <br />the highwall to result in gentle slopes extending from the base of the highw II to the vegetated <br />berm along the permit boundary and Hwy 141. Vegetative cover for the 60, 00 cy stockpile of <br />-3" material, located at the Phase II portion of area A, was well established. vidence of surface <br />erosion from concentrated upland drainage crossing the stockpile was obser ed at the west and <br />east ends of the stockpile. The operator had installed erosion resistant rock li ing throughout the <br />drainage ditch running along the top of the eastern portion of the stockpile. During the 8/7/01 <br />inspection, DMG observed that upland drainage conveyed by the rock lined itch had eroded a <br />gully at the end of the rock lining in the steep outslope of the east end of the stockpile. <br />Subsequently, the operator installed aflume-shaped metal collar at the head of he gully and placed <br />large rock in the bottom of the gully to control the erosion. However, giv n the quantity and <br />velocity of drainage at this location, evident by the existing gully erosion, plan for a ditch design <br />with continuous rock lining and energy dissipating structures will be requir d if the stockpiled <br />material is not removed in the near future. Rules 3.1.5(3) and 3.1.613) req Tres an operator to <br />stabilize affected lands, to control erosion and sedimentation to protect ar as outside of the <br />affected land. <br />As noted in the attached DMG memo, DMG can conditionally approve th portion of TR-01 <br />addressing the highwall. The condition for DMG approval for the highwall to r main at its present <br />configuration is that the operator must eliminate the potential route for rock r II out to Hwy 141 <br />provided by the access road gap in the existing permit boundary berm. Howev r, the operator has <br />not demonstrated to DMG's satisfaction that the 60,000 cy material stockpile i stable. Therefore, <br />DMG cannot approve the portion of TR-01 addressing reclamation of the sto kpile at its present <br />