Minntac considers new route for unwanted
By John Myers
Duluth News Tribune
Published December 7th, 2004
Where do you put 7.2 million gallons of unwanted water
That's what officials of the Minntac taconite plant are
trying to determine, waiting for a Minnesota Pollution
Control Agency decision on the company's plan to pump
water from its taconite tailings basin into a nearby river.
After studying the issue for more than three years, agency
officials say they'll complete a draft Environmental Impact
Statement early in 2005.
The agency is considering several options for the water,
including the original plan to route it down the Dark
and Sandy rivers.
A new option would send the water south, into the West
Two Rivers Reservoir, which flows into the St. Louis River
system and, eventually, into Lake Superior.
The problem is that the water contains sediments and
sulfates, and the sheer volume makes it an issue no matter
where the agency looks for an outlet.
"We're still working on it. The draft (Environmental
Impact Statement) is over 600 pages now and looks at 10
to 12 options," said John Elling, agency project
They include one to refrain from taking action, with
no additional diversion allowed out of the Minntac tailings
basin. Another is to require a treatment plant to clean
the water before it's released. Only one other Minnesota
taconite plant, Northshore Mining, is required to treat
water that leaves its tailings basin.
In 2001, officials of the U.S. Steel-owned plant first
proposed to divert 5,000 gallons of water per minute --
2.6 billion gallons per year -- out of its tailings basin.
That basin is where the unused mining waste rock from
the taconite processing plant goes, along with millions
of gallons of water, every day.
Minntac uses about 250,000 gallons of water every minute
of every day for various parts of the taconite making
process, including separating ore from rock, cleaning
air pollution scrubbers and moving waste rock into the
The basin, a giant storage area ringed by more than nine
miles of dikes, can hold 18 billion gallons of water.
It's not in danger of overflowing, but company officials
say discharging water would extend the basin's life.
For 30 years, Minntac has for recycled much of that water.
But the repeatedly recycled wastewater is becoming choked
with solids, and the company wants to let some of it out.
Using cloudy water to make pellets can affect their quality
and foul plant equipment, Pollution Control Agency officials
The water diversion "is something we really still
need," said John Armstrong, U.S. Steel spokesman
in Pittsburgh. "After 30 years of recycling water,
we need to make some changes."
Minntac has a permit that allows 2,200 gallons of water
per minute to "seep" out of the tailings basin.
Elling said diversion would allow a more controlled release.
NO EASY ANSWER
Minntac and the Pollution Control Agency have encountered
environmental concerns in almost every direction they
have looked to dump the water, which contains sediment
and small amounts of pollutants, such as sulfates.
The volume could overwhelm small streams and raise stream
temperatures, both of which could affect fish populations
and stream ecosystems.
Sulfates are considered a possible human health issue
because they can trigger mercury in the streams to become
toxic. The mercury, called methyl mercury, can build up
in fish and in people who eat fish.
"The impact of mercury is the biggest issue no matter
where the water goes... but the volume of water is probably
a bigger issue on the Dark (river). It would have the
biggest impact there," said Karl Koller, Grand Rapids
area fisheries specialist with the Department of Natural
Resources. "Adding that much warmer water might put
the river past the temperature that will sustain trout."
Minntac officials asked for the Environmental Impact
Statement to determine what effect the diversion would
have on local waterways.
The original plan to pump the water north into the Dark
River was met with opposition from trout anglers, including
the Grand Rapids Trout Unlimited chapter. The river is
one of the best naturally producing trout streams in the
A proposal to send the water east into the Sandy River
brought concerns about downstream areas of wild rice,
which are sensitive to water levels and where sulfates
can damage rice germination.
An option looking at the St. Louis River system almost
certainly will bring warnings from downstream interests,
including environmentalists and anglers in Duluth.
Elling noted that other taconite plants have water diversion
permits; the Minntac request is not unprecedented.
SULFATES TOP CONCERN
Studies have shown sulfates as the biggest problem, but
not an insurmountable one, said Pollution Control Agency
hydrogeologist Richard Clark. Concerns over heavy metals
in the tailings water have proved unfounded, he said.
"Fortunately, the concentrations of metals and mercury
in both the tailings basin water and the seepage have
been very low," he said. "Metals are not our
primary concern. It's sulfates."
The DNR's Koller said the best option may be some sort
of treatment of the water to remove sulfates.
"We're going to be learning more about that in the
next few weeks," Koller said. "Treatment of
some sort may be the best way to solve one of the bigger
problems. And then we still have to decide which way to
send it or decide to split up the volume several directions."
The public will have 45 days to comment on the draft
plan when it's released next year, and a public meeting
on the proposal is expected. A final plan also would have
a public input period before the plan goes to the full
Pollution Control Agency citizens board for approval,
possibly later in 2005.