2008-05-21_INSPECTION - M1978091UG

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(Page 3) MINE ID # OR PROSPECTING ID # M-1987-091 UG INSPECTION DATE 5/6/08 INSPECTOR'S INITIALS RCO. AJW It appeared during the current inspection that the melting of the snowpack in the vicinity of the site had been underway for a period of several weeks, since roads and open slopes were fairly dry, and runoff could continue since snow still existed in the shaded and wooded areas. Gulch flows were estimated at 100 to 200 qpm immediately above the 6 level pad much of which was intercepted by the liner installed in 2007, and conveyed effectively throughout its length to its terminus ultimately discharging this flow amount onto the wooded hillside Flow rates were large enough that most of the runoff was reaching the the gulch as surface flow, with little or no infiltration occurring. Recognizing the erosion that was occurring, 2 workers were actively attempting to install light plastic sheeting in a temporary manner from the lower end of the geotextile liner down through the woods to the gulch below the dump. The flow was forceful enough to make such installation difficult, and useless after a short time; the plastic was soon carried down the slope. Soon afterward, while mine personnel and inspectors watched, the earth on the hillside became so saturated by the gulch flow that a localized portion of it blew out and ran down the gulch below the permitted area, knocking down trees and carrying rocks and sediment The amount of the failed hillside that moved was estimated to be 200 cubic yards with larger debris coming to rest on the old road leading to the Gold Quartz mine while the water and finer sediment continued down. Several mine personnel drove immediately down to the outlet of Deadman Gulch at Hwy 149. The Division inspectors assessed the continued runoff and condition of the failed hill slope, and concluded that there would be further erosion and sediment transport down the gulch, but small likelihood of additional large slope failure. Division inspectors and the operator's agent onsite agreed on the need for identifying the needed additional structural controls and installing them promptly (in the interest of quickly ensuring site stability). Inspectors drove to the gulch outlet at the highway, and observed a culvert clogged with gulch mud, and CDOT personnel clearing gulch mud from a 200-foot stretch of hi hway pavement, while an officer with the county sheriff controlled traffic. Farther down the gulch, below the highway, inspectors observed that muddy water had entered a landowner's pond. Flows had greatly diminished, and there was no coarse material, but the flow was still very muddy. The gulch distance from the failure to the first highway crossing is 2700 feet or more and the additional distance to where mud was last observed is over 400 feet. Division inspectors were unable to closely inspect the Lake Fork at or below its confluence with Deadman Gulch. The slope failure was caused by an activity carried out by or on behalf of the operator inside the permitted area but the failure and the portion of the gulch affected were outside the permitted area due to incomplete construction of the diversion structure Damage to areas outside the permitted area boundary is a possible violation (pursuant to CRS 34-32-116(7)(8) (h) and (0) As noted on page one the topics of "Hydrologic balance," "Erosion/sedimentation " and "Offsite damage" are shown as possible violations. This matterwill be scheduled for hearing before the Mined Land Reclamation Board. The operatorwill be sent a separate letter advising him of the scheduled hearing, possibly to be held at the June or July 2008 meeting. If the operator has installed structures or implemented certain practices, in efforts to correst the problem of uncontrolled sedimentation, please contact this office and/or bring evidence of such to the Board hearing. An issue identified in the 6/8/07 inspection report involved changes to the operation, activities, methods and structures, that are being implemented without the appropriate revisions being made to the DRMS permit. Even though the changes may be proposed or implemented to comply with another agency's requirements, the changes must still be made to this permit also. If the changes are operational they may be added as a technical revision (TR). If the changes involve addition of lands outside the permitted area, such as the widened road and lower gulch limestone treatment or diversion pipe for example, they must be added as an amendment (AM). Currently, there are onsite changes that have not been approved by this office as technical revisions or amendments, and there may be other changes being planned The operator is reminded that this permit is a DMO and it is important that structures and plans be engineered and certified if appropriate and that revisions are submitted to this office for proper review. At this time, this is not noted as a problem, since the other issues identified in this report will be corrected through the proper submittal of materials for permit modifications. No further items were observed during the inspection. Responses to this inspection report should be directed to the Division of Reclamation, Mining and Safety, 701 Camino del Rio, Room 315, Durango, Colorado 81301, Attn: Bob Oswald; phone no. 970- 247-5193. (As of 10122/07 we have a different room number. Please revise your records as necessary.) Cont.