_INSPECTION - C1994082 (46) - Laserfiche WebLink

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Yoast Mine Phase I bond release, pg. L pre-inspection office visit, we discussed approximate original contour(AOC) restoration, large- scale stabilization, and surface water runoff(erosion) control which are all reclamation requirements to be completed in accordance with Colorado Rule 3 and the approved DRMS permit in order to secure Phase I bond release. We also discussed inspection of structures approved by DRMS for permanent retention to facilitate the post mining land use of rangeland including permanent water impoundments, and roads. During the inspection days (July 15-16), participants walked through large portions of the release request area,to allow for visual assessment of compliance with pertinent requirements, including backfilling and grading, site stability, blending of regraded land to undisturbed areas, and drainage control. We made observations of AOC restoration, surface water runoff control and surface erosional stability, and retention of permanent structures as we walked all of the pm channels. AOC restoration observed throughout the reclaimed areas closely resembles the pre mining landscape, and blends extremely well into surrounding undisturbed areas. The essential hydrologic functions recreated by the pm channels resembles the pre-mining landscape, helps provide stability for surface water runoff and reclaimed slopes, and facilitates the post mining land use of rangeland. We took slope measurements in several areas along pm channels, reclaimed slopes, and checked for stability of pond embankments. Several digital photographs were also taken during the inspection and attachments to Mr. Mathew's inspection report will include those observations. We began the field inspection on July 15th at the head of YPM-1-1 channel, and walked its entire length making the observations noted above. Observations and subsequent stops and observations during the inspection are as follows: The upper East Fork of YPM-1-1 was lined with cinder/volcanic rip-rap (the smaller material had washed further down the drainage) and we measured a representative slope in the channel at 18%. Minor gully erosion has occurred in the upper YPM-1-1 watershed and a deep gully has formed along the north boundary of large fenced woody-stemmed plant reference area where a representative slope of 5%was measured. Mr. Mathews recommended grading and installing a series of rock checks to mitigate the problem, and that the fencing around the woody-stemmed plant reference area be repaired and monitored. More substantial erosion re-appears further down the slope and will need to be stabilized in accordance with the Rill and Gully Plan of the approved permit. Similarly, a ditch has formed on the west end of an aspen stand near the channel as a result of runoff. This is the area that serves as the subject of the landowner's concerns including erosion and weed infestation (Canadian thistle). The thistle patch will need to be treated in accordance with the weed control plan of the approved permit. Smaller rills exist below the aspen stand and appear to be healing,but Mr. Mathews recommended that minor handwork repairs such as surface scratching and installing a series of rock check structures be conducted. The landowner had previously expressed an interest in having a retention pond constructed in the area of concern,but that now appears to be unnecessary in light of the recommended remedial actions. We also noticed a gully running along the fence of an adjacent reference area that has created rills parallel to the channel. Mr. Mathews recommended that the