Beneath the Mojave Desert floor, in rugged mountains whose barren facade belies a biologically diverse ecosystem, a sizeable gold deposit is being mined for all it is worth.
Mountain lions, coyotes, and wild burros roam the hills and gullies, and a virtual forest of Joshua Trees and native plants thrive in the high desert terrain where Viceroy Gold Corp. of British Columbia is extracting precious ore from the Castle Mountain Mine. Desert Big Horn sheep sometimes stop in fearless fascination to watch miners scooping out the ore and trucking it away.
In this remote and extraordinary desert landscape, Castle Mountain Mine, California's third largest gold mine, operates around the clock, digging rock from a huge open pit and leaching it with cyanide to extract the gold.
Adding to the environmental sensitivity, the mine is situated next to the Mojave National Preserve, and on the periphery of prime habitat of the protected Desert Tortoise that straddles the California-Nevada border 60 miles south of Las Vegas.
When mining ceases, the BLM requires operators to cleanse and detoxify cyanide leaching process and remove all manmade objects, including buildings, fences, pipelines, powerlines, machinery, tanks, concrete slabs, signs, and roads. The open pit, leached ore, and overburden (rock overlying the ore) cannot be removed, but the landscape that covers or surrounds them must be reshaped to match the original contour. Native vegetation is replanted. Eventually, after the mining operation has met clean air and clean water standards, the monitoring apparatus is removed.
"Our goals for reclaiming mined land have expanded in the past decade as we have learned more about how to maintain, enhance, and restore the health of ecosystems," said Ed Hastey, BLM state director for California.
The BLM has developed California standards for managing cyanide at the 10 gold mines operating on its land. Besides Castle Mountain, several other mines under California BLM jurisdiction, including McLaughlin in the Napa Valley and Hog Ranch in northwestern Nevada, are undertaking extensive reclamation.
When Viceroy struck it rich in the California desert a decade ago, the company faced a big challenge. Since it takes 100 tons of rock to produce a single ounce of gold, millions of tons would have to be excavated, crushed, and leached. The ecologically disruptive operation would have to obtain more than four dozen permits and comply with complex environmental and mining laws.
Long before the BLM and San Bernardino County would pen-nit Viceroy to begin digging for gold, the company had to demonstrate that it would return the site to its natural condition as closely as possible. Viceroy was allowed to disturb 890 acres of the 2,885-acre mining property.
Viceroy prepared a voluminous Environmental Impact Statement/Environmental Assessment Report that cost $3 million and filled a bookshelf, helped The Nature Conservancy create a 150,000-acre Desert Tortoise preserve, bought 745 acres of prime tortoise habitat for the BLM as mitigation for building its mine and access road, and contributed $2 million to an environmental enhancement fund administered by the Trust for Public Land for restoration.
"We know we can never totally erase our footprints, but we have set out to demonstrate a commitment to protect the environment," said Chris Mitchell, Viceroy's senior vice president. "We have borrowed and built on ideas developed at other mines, and I think environmentalists realize that with respect to environmental protection, what we have said we would do, we have done."
Joan Reiss, an environmental consultant who in 1990 headed The Wilderness Society in San Francisco when it opposed, and tried to halt, the opening of the Viceroy mine, says environmentalists are pinning their hopes on its reclamation program.
"After we realized we couldn't stop the mine, our goal was to have Viceroy adhere to the highest environmental standards possible," Reiss said. "We believe these are precedent-setting reclamation requirements, more environmentally sensitive than probably any other mining operations we know about. The most critical issues are the monitoring of the groundwater and the reclaiming of the land. We hope it will be 100 percent successful."
By the time the mine began to operate in 1991, Viceroy and its 25 percent partner, MK Gold Co. of Boise, Idaho, had invested $80 million, including $5 million to meet environmental concerns, Mitchell said.
The main access road to the mine crosses prime habitat where up to a dozen tortoises live per square mile. Viceroy's incidental take permit from the U.S. Fish and Wildlife Service prohibits killing or injuring more than seven tortoises during the 10-year life of the mine, which may be extended to 20 years. The mine itself is at 4,400 feet elevation, too high for most tortoises, but to be sure, Viceroy encircled the area with a 25,000-foot special fence that the creatures cannot penetrate.
The company posted a reclamation bond with the BLM and San Bernardino County that fluctuates in value depending on the extent of land reclaimed, and this year it is $1.6 million. Viceroy also put up a $400,000 bond to assure protection of surface and groundwater.
To guard against air pollution, dust from crushing tons of ore into pea-sized pebbles is captured inside a tent-like structure that covers the crushed ore stockpile. A huge pair of vacuums collects dust generated in other parts of the plant.
To protect groundwater and birds, the toxic solution of diluted sodium cyanide- the only chemical commercially available on a large scale that can extract gold from ore - is kept in steel tanks instead of open ponds. Dissolved gold is retrieved through an intricate filtering and melting process, and the cyanide solution is reused. Any cyanide flushed from the leach pads during infrequent rainfall is captured in a system of lined pad, berms, and ponds covered with netting to protect birds until it can be recycled to the leaching process.
The state of California requires that mines be operated in compliance with the California Environmental Quality Act, and the land returned to a useable condition for wildlife habitat or recreation in accordance with the 1975 Surface Mining and Reclamation Act, administered by the Department of Conservation.
"Viceroy's reclamation plans include measures that exceed others that came before it," said Bob Anderson, BLM deputy director of minerals and energy. "For example, they will make sure the density and diversity of plants they replace are at least equal to what existed before."
Mitchell said 35 acres have been reclaimed, and after Viceroy closes the mine, it will have reclaimed a total of 862 acres including 771 at the mine and an additional 91 acres of nearby clay pits. The open pit, which will be 620 feet deep when exhausted of its ore, will be nearly filled, using earth from a proposed adjacent open pit mine that Viceroy hopes to dig.
"Viceroy has been a partner with the BLM in taking that extra step and spending that extra dollar to ensure that reclamation in a desert environment is successful," Hastey said.
"When we leave this site, it will be in a safe condition that doesn't pose a hazard to humans or wildlife, interfere with water flows, or create dust," Mitchell said. "Over time, as vegetation is reestablished, the disturbed areas will closely resemble other topographic features."
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