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Closeout Report <br /> London Mine Venture <br /> M-80-250 <br /> This site was inspected several times between 1997 and 1999. The site consists of 4 <br /> adits associated with the Water Tunnel portion, one adit associated with the London <br /> Extension portion and one adit associated with the Butte Tunnel portion of the <br /> operation, approximately 16 acres covered with waste rock, and approximately 7-8 <br /> acres covered with mill tailings and tailings impoundments. There are several <br /> permanent structures at the site, including an office building and maintenance shed. <br /> There are numerous portable structures at the site as well as numerous pieces of <br /> mining equipment. <br /> In 1997, the inactive mine program effectively safeguarded the London Extension and <br /> Ophir adit, on the Water Tunnel level, during construction of a treatment system for the <br /> mine drainage from the London Extension Tunnel. A portion of the structure outside <br /> the London Extension Tunnel was reconstructed and locked, effectively controlling <br /> access to the mine workings. The Ophir adit entrance was backfilled during <br /> construction of a settling pond for the London Extension treatment system. <br /> In 1998, there were three open adits at the site. During the spring of 1999, two of the <br /> adits collapsed. Original reclamation plans for the $11,400 of bond money was to <br /> safeguard the three mine adits. Due to the collapse of two of the adits, the reclamation <br /> plan was changed to include construction of several diversion structures and capping of <br /> the Butte mill tailings. <br /> Capping of the Butte mill tailings was completed by Frontier Environmental Services, <br /> 770 Simms Street, Suite 110, Golden, Colorado, using a backhoe and front-end loader. <br /> Dolomitic waste rock from the Butte Tunnel was used to cap the approximately 4 acres <br /> of mill tailings and armor the drainage channels. The tailings were capped with <br /> approximately 2-4 inches of material. The capping should reduce wind and water <br /> erosion from the site and may allow for vegetation to become established on the near <br /> neutral tailings. The entire area was seeded. A total of $6,628.75 was spent on this <br /> portion of the reclamation project. The work was completed in October, 1999. <br /> The Butte Tunnel was safeguarded with a steel grate and three diversion structures <br /> were constructed by Mining & Environmental Services LLC, P.O. Box 1511, Idaho <br /> Springs, Colorado. One diversion structure was constructed along the road to <br /> American Flats north of the site. This will effectively reduce the amount of water <br /> coming in contact with waste rock. A second diversion was constructed along the <br /> tailings impoundment. A diversion ditch had been previously constructed, but did not <br /> have sufficient slope or capacity for the site. A third diversion structure was <br /> constructed above the Butte Tailings to prevent a small perennial stream from flowing <br /> through the Butte Tailings. In addition, an upland diversion structure on the south edge <br />