Laserfiche WebLink
PERMIT #: M-2009-076 <br />INSPECTOR'S INITIALS: MAC <br />INSPECTION DATE: September 17, 2015 <br />were produced using only gravity separation; future milling will include the flotation circuit. <br />The tailings impoundment was inspected and the Division observed that the composite liner, which was <br />entirely visible during the last inspection, had since been covered with waste rock. According to the Operator, <br />the waste rock was placed on the surface liner in order to protect it from weathering. The waste rock was <br />removed from the existing waste rock pile located immediately north of the tailings impoundment and was <br />mechanically placed on the liner. The liner was not designed to have unprocessed waste rock placed on top of <br />it and the approved Mining Plan does not contain a provision for covering the liner in the event it is exposed <br />for prolonged periods of time. The surface liner consists of a Geocomposite filter layer which can typically <br />withstand exposure to the elements for many years before it starts to break -down. The Division spent a <br />considerable amount of time reviewing the design of the tailings impoundment, including in-depth analysis of <br />the stability of the impoundment. The engineering analysis was based on the approved plan to hydraulically <br />place coarse and fine tails on the liner, not large pieces of angular waste rock. In addition, the angle of repose <br />for the waste rock will differ from that of the tails and calls into question the stability of Bench # 1 should tails <br />be placed onto the waste rock. <br />The Division has serious concerns regarding the integrity of the composite liner system. The placement of the <br />waste rock onto the liner will require an engineering analysis before any additional material is placed onto the <br />liner. In addition, it is not apparent how the material may be removed without compromising the integrity of <br />the liner. The unapproved placement of waste rock onto the liner has been cited as a problem and will require <br />corrective action by the Operator. Please see the first page of this report for additional information <br />Revegetation: <br />The Division observed diffuse knapweed in the area of the mill facility. Diffuse knapweed is a Colorado List B <br />noxious weed. Pursuant to Hard Rock Rule 3.1.10(6) methods of weed control shall be employed for all <br />prohibited noxious weed species. A review of the permit file found that the Operator does not have an <br />approved weed control plan. The Operator shall develop a weed control plan which includes the following <br />information: <br />a) a list of potential species of noxious weeds that may occur on the site <br />b) a description of the various control measures that will be employed for any noxious weed species, i.e. <br />mechanical, chemical or biological control methods <br />c) a monitoring plan which specifies how often the Operator will monitor for weeds, the timing of planned <br />monitoring and the actions to be taken if noxious weed are identified <br />d) a post-treatment monitoring plan to determine effectiveness of weed control methods <br />e) a commitment to adhere to the approved weed control plan for the life of the mine <br />The presence of noxious weeds on-site has been cited as a problem and will require corrective action by the <br />Operator. Please see the first page of this report for additional information. <br />This concluded the inspection. <br />Page 4 of 6 <br />