Geotimes
Energy & Resources
Controversial mineral deposit sold
Mineral Resource of the Month: Lead
Controversial mineral
deposit sold
Since it
was first discovered by Exxon in the 1970s, the Crandon copper-zinc deposit in
Wisconsin has been an on-again-off-again venture for mining companies and a source
of apprehension for some local residents. Nestled in forest in the Wolf River
watershed, one of the last pristine rivers in the Midwest, the deposit contains
almost a million metric tons of copper and about 4 million metric tons of zinc,
making it one of the top 20 volcanic-associated metal sulfide deposits in the
world — and the largest in North America. The area also contains sacred sites,
burial sites and wild rice stands in small lakes, harvested by Native American
tribes from nearby reservations.
The Crandon deposit is set in Wisconsin’s
northern woods. Photo by Tom Fitz.
The deposit’s unique cultural and economic value has stood at the heart of
a decades-long struggle to obtain mine permits. In October, the surprise sale
of the Crandon deposit by Nicolet Minerals Company to two local Native American
tribes ended speculation and plans for mining zinc and copper in northern Wisconsin.
“I feel so grateful because we’ve been able to protect many generations,
and I literally can’t stop feeling good about that,” says Tina Van Zile,
vice chair of one of the tribes and the new president of Nicolet Minerals. “To
know that we will be able to ensure things as clear water and plants and wild
rice … let alone all the burial sites that will be intact.”
The Crandon deposit originated in Proterozoic ocean crust, now incorporated into
the North American craton. The mineral body sits below 125 feet of porous glacial
till. Its setting complicates water and waste disposal issues affecting groundwater
and nearby streams and lakes, concerns that have haunted the Crandon deposit mine
for almost 30 years.
After exploration in the 1960s and 1970s, Exxon started the permitting process
for the first time in the early 1980s. Environmentalists and Native Americans
intensified their protests. In 1986, the company withdrew, as zinc and copper
prices plummeted. When the market for metals strengthened, the company once more
sought a permit to mine in 1994.
In the meantime, the Wisconsin legislature tightened regulations on mining. “By
virtue of our laws and rules, we require an extensive evaluation and more or less
that compliance be proven up front,” says Larry Lynch, mining team leader
for the Wisconsin Department of Natural Resources (DNR). “That’s a tall
order.”
Also, he says, the most recent Crandon project changed hands several times, with
several modifications to mining plans, further complicating and delaying the permitting
process: Rio Algom bought out partner Exxon, and then BHP Billiton, one of the
largest metal mining companies in the world, acquired Rio Algom. Adding further
discord, environmental coalitions questioned the jobs and income the mining companies
promised; industry accused local citizens of knee-jerk environmentalist backlash.
“This was an important resource that needed to be developed,” says Dale
Alberts, a former president of Nicolet Minerals. Had it gone forward, the 30-plus-year
mining operations could have given about a $4-billion boost to “a very poor
county” — Wisconsin’s second poorest — he says.
Two independent
appraisers for the state, which briefly considered buying the land in 2002, judged
the proposed mine site worth about $52 million or $91 million, with mining rights.
However, the ability to use those rights — and the issuance of a permit —
remained uncertain because of lingering concerns over water contamination.
Cores confirmed what magnetic anomalies
indicated was a huge metal sulfide ore body, filled with chalcopyrite (shown here)
and sphalerite. Photo by Tom Fitz.
In addition to Exxon’s initial investments, including permitting costs, drilling
and other exploration, tens of millions of dollars went toward the development
of a mine, with pollution prevention plans in mind. Rio Algom alone invested millions
of dollars into the permit application and in creating a cutting-edge design for
remediation and pollution prevention during the mine’s life. According to
Nicolet Mineral’s most recent plans, the underground mine would be refilled
with a mixture of pyrite tailings and cement in order to isolate any sulfur that
could cause acid drainage on the surface. Other measures, including intense wastewater
treatment and a blanket of grout over the mine, would further control contamination
and water flow. DNR also created innovative and extensive groundwater and contaminant
flow models, Lynch says.
Nicolet Mineral’s own models show, however, that future groundwater effects
might be unavoidable, requiring constant monitoring even hundreds of years after
the mine shuts down. DNR could not allow the project to go forward without the
development of an acceptable plan to avoid such problems.
Such obstacles in the permitting process may have played a role when the Northern
Wisconsin Resource Group, a regional lumber company that is family owned and managed,
bought the land last April for an undisclosed amount. The company intended to
find an experienced mining partner: None stepped forward. Months later, on Oct.
28, the Sokaogon Chippewa Community Mole Lake Band (which earns revenue from gambling
on its reservation) and the Forest County Potawatomi Community bought Nicolet
Minerals and the Crandon land for $16.5 million, including all mineral rights.
Although he hesitates to speculate on the impact of Crandon’s sale on mining
in Wisconsin, Lynch notes that because the state legislature continued to change
regulations — passing a “mining moratorium” act in 1998 —
exploration applications have stopped. Surveys have shown industry perceives Wisconsin
as an unfavorable place to do business. The Crandon project withdrawal probably
will not improve that negative perception, Lynch says.
Van Zile says that for the foreseeable future the tribe does not intend to exercise
the mineral rights. “I can’t say what a new council would do,”
she says. “As far as right now, there’s no technology that’s safe
enough to pull this off.”
Naomi Lubick
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Mineral
Resource of the Month: Lead
U.S. Geological Survey Lead Commodity Specialist Gerald R. Smith has prepared
the following information on lead — one of the world’s most widely used
and recycled metals.
The United States is a major producer and consumer of refined lead, representing
almost one quarter of total world production and consumption. Two mines in Alaska
and six in Missouri accounted for 97 percent of domestic lead production in
2002. The United States also imports enough refined lead to satisfy almost 20
percent of domestic consumption. Other major producers or consumers of refined
lead in the world are Australia, Canada, China, France, Germany, Italy, Japan
and the United Kingdom.
Lead is a very corrosion-resistant, dense, ductile and malleable blue-gray metal
that people have used for at least 5,000 years. Ancient Greeks and Romans used
lead for building materials, pigments for glazing ceramics and pipes for transporting
water. The castles and cathedrals of Europe contain considerable quantities
of lead in decorative fixtures, roofs, pipes and windows. And in the United
States, early uses of lead were in ammunition, brass, burial vault liners, ceramic
glazes, leaded glass and crystal, paints, pewter, solders and pipes.
In the 20th century, however, the phenomenal growth of motor vehicle manufacturing
dramatically altered the market profile for lead, as demand grew for its use
in starting-lighting-ignition (SLI) batteries and gasoline additives. Use of
lead in the production of such batteries for motor vehicles accounted for 70
percent of the reported consumption of lead in the United States by 2003. In
addition, lead use increased in batteries for a wide range of vehicles that
are not gasoline-powered, including wheelchairs, golf carts, airport ground-support
equipment, industrial forklifts and mining vehicles.
Other technological advances during the last century further prompted greater
use of lead in batteries for uninterruptible and emergency power in hospitals
and national defense installations, as well as for telecommunications and computer
systems. Lead use in all battery types reached 87 percent of reported consumption
by 2003. The use of lead for radiation shielding in medical devices, video displays
and military hardware also became important new markets for the metal in the
latter part of the 20th century.
Bans on lead — because of health risks to people — essentially eliminated
its use in gasoline and paint additives during the past 30 years in the United
States. The use of lead in SLI automotive-type batteries, however, has continued
to grow steadily. Consequently, domestic recycling of spent lead-acid batteries,
particularly SLI batteries, has also risen in response to environmental concerns
about lead. By 1980, recovery of lead through the recycling of old scrap in
the United States had reached 581,000 metric tons, representing 51 percent of
U.S. refined lead production and 69 percent of all refined lead consumed domestically.
Today, almost 80 percent of U.S. lead production is derived through recycling
under strict environmental standards and satisfies about 80 percent of U.S.
refined lead demand. The lead-acid battery, with a 97-percent recycling rate,
is now the most highly recycled consumer product in the United States.
Of the 1.12 million metric tons of lead recycled in 2003, about 99 percent was
produced by seven companies with 15 plants in 11 states across the country.
Most of the recycled lead was recovered either as soft lead or lead alloys to
be reused in the manufacture of lead-acid storage batteries.
For more information on lead, visit the USGS
minerals Web site.
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