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Source: SME disk II: “Reclamation practices at Homestake’s McLaughlin
Mine” - Krauss
The McLaughlin gold mine, owned and operated by Homestake Mining Co.,
is located in the coastal thrust fault of northern California. Before
mining began at this site in 1985, it was worked for over 100 years for
the production of mercury. At this time, the presence of gold was
unknown. By 1978, the area had not been reclaimed and was in poor
condition.
Photo: Aerial view of Homestake’s McLaughlin Mine in California.
Extensive research and engineering plans were evaluated to address the
environmental impact. A total of six years were spent in planning
and preparing the site for mining. Studies were conducted to determine
the best location for disposing of tailings and waste rock. Reclamation
is an ongoing process and has occurred during the years the gold mine has
been in existence.
The mine is located on a ridge between two watersheds at an elevation
of approximately 2,000 feet. Its location is advantageous due to
the fact that the water flow is limited and does not have to be diverted
to another location. The site is in a remote area in a sparsely populated
surrounding area. Tourism, agriculture, and the premium wine grape
industry largely dominate the economy for the region.
The McLaughlin Mine has facilities in three California counties.
It is for this reason the mine is under the authority of three different
air quality management districts, two state departments of fish and game
regions, a state water resources board, a regional water quality control
board and the Federal Bureau of Land Management. In total, 327 permits
were obtained before any gold was poured.
Due to the popular political views held by many northern California
environmentalists, this project was under public scrutiny from the beginning.
Goals of the reclamation were to be free of any technical errors, as educational
as possible, and approved by the affected communities. A local chapter
of the Sierra Club reviewed project documents including site evaluation
studies and engineering reports. Their appointed technical experts
came to the conclusion that the proposal was environmentally sound.
Photo: Waste dump reclamation at Homestake’s McLaughlin Mine in California.
Independent experts have monitored the success of the reclamation.
Erosion was controlled. Soil stripped from the tailings basin and fresh
water reservoir were saved for future revegetation. A fresh water
reservoir created a new habitat for a rich and diverse wildlife community.
The reservoir attracts waterfowl, deer and small mammals, as well as predators
including mountain lion, bear, coyote, fox, and raptors. An environmental
studies field station will be built at the conclusion of mining to serve
an educational purpose. Data will be compiled to provide useful information
including annual aerial photographs, surface and ground water data, aquatic
ecology, wildlife, and vegetation surveys.
The planning and design of the reclamation project is consistent with
trends in this field to provide technically sound engineering in a responsible
manner. This project demonstrates the benefits of early and
thorough involvement with regulatory agencies.
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