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Original article
10/14/07 - GREG MARTIN -
Charlotte Sun
Staff Writer
Expert
sees benefit in reservoir offer Mine scientist not worried about
contaminants
Reclaimed phosphate mine
sites should be used to store water that could be used to maintain the
Peace River's flow during dry spells or boost drinking water supplies,
according to Peter J. Schreuder, a water resource consultant for the
mining industry.
Schreuder, who has worked as a professional environmental scientist in
Florida for some 35 years, said he has recently conducted studies that
showed mine sites naturally boost the flow of the Peace River and don't
contribute contaminants to water resources as some environmentalists
suggest.
Schreuder was one of several environmental consultants who were asked by
the Sun for their opinions this week about a proposal from the Mosaic
mining company to provide water storage sites in exchange for a
settlement of litigation from several area counties.
Specifically, Mosaic has offered to provide a site for a 6 billion
gallon water supply reservoir on a mined or unmined site in
DeSoto or Manatee county. The Peace River/Manasota Regional Water Supply
Authority would build and operate the reservoir.
The company has also offered to store water on mine sites, apparently in
pits or clay-settling areas. That water would be discharged into the
Peace River to help the river stay above its minimum flow.
In exchange for those and other provisions, the authority and Charlotte,
Lee and Sarasota counties would drop all litigation and never object to
Mosaic's mining proposals again for the next 30 years.
The company owns some 100,000 acres yet to be mined in the Peace River
watershed.
Schreuder said he sees a potential for the mining industry to use its
lands to the benefit coastal communities.
And donating a mined-out landscape to the water authority would save the
mining company tens of millions of dollars in reclamation costs.
Schreuder cited the fact that, under its permit from the Southwest
Florida Water Management District, the authority must stop withdrawing
water once the flow of the river at Arcadia drops below 130 cubic feet
per second.
Since early this year, the district allowed withdrawals even when the
river's flow drops below that cutoff under an emergency water shortage
order.
"If the mining people during big storms can hold back some of that
(storm) water and release it when the river is close to the 130 cfs
cutoff, the authority could continue pumping," Schreuder said. "That
opportunity is there. It has never been explored because they have this
adversarial relationship."
Schreuder's opinion is at odds, however, with those of other ecologists
or environmentalists who suspect reclaimed mine sites contribute
contaminants to water resources and drain down surrounding wetlands.
Dr. Sydney Bacchus, a professional hydroecologist who recently testified
about impacts stemming from rock mines in Lee County, called Schreuder's
theories examples of a "fantasy world."
Bacchus said it's a false assumption to believe water can be "stored" in
mine pits.
That's because the ground naturally stores water, and that water
naturally moves through the ground -- and through pits in the ground.
The excavation of pits replaces the ground's natural storage capacity
and alters the natural movement of the groundwater, she said.
The pits also increase evaporation, and that water is replaced by
draining the water table, she said.
"The more 'storage' they claim they are providing, the more they are
dewatering the aquifer to make room to 'add' water," she said.
"That's generally when the ultimate death of all the native vegetation
or trees on surrounding properties is initiated," Bacchus said. "That's
also what initiates the mass invasion of alien and other invasive
species you pay millions of tax dollars to try to control."
Bacchus also said she has no evidence at any of the "countless mine pits
I have evaluated throughout Florida" that supported Schreuder's claims
that mine sites shed more water into streams after they've been mined.
"My professional opinion is that the pits will dewater the aquifer
system and associated ecosystems (including surface waters) and the
irreversible adverse impacts will extend off-site for many miles," she
said.
Some environmentalists have also suggested a public water supply should
be drawn from water draining off mine sites. They cite a 2001 study of
the former Tenoroc Mine excavated by Borden Chemical in the 1960s.
The study, conducted for the U.S. Environmental Protection Agency by the
consultant Tetra Tech, was never officially approved by the agency.
However, the study found elevated levels of heavy metals and
radionuclides in samples of soil, clay and water on the Tenoroc site.
Some of the levels exceed the EPA's cancer risk screening standards.
EPA officials have also indicated such contamination could likely be
found at nearly a dozen other Central Florida mine sites.
That raises a question as to whether such contamination could be getting
into drinking water supplies, said Jim Cooper, founder of Protect our
Watersheds.
"Not being a doctor or a biologist, I don't know what dangers were
pointed out in the Tenoroc study," Cooper said. "Anything that can get
in the aquifer can obviously go lots of places. If there's a risk there,
it ought to be looked at pretty closely."
Cooper has urged the county commissions to slow down their deliberations
to examine such issues.
But Schreuder has concluded water draining from phosphate mines poses no
health concerns. He bases his opinion on a study he conducted in 2002
for the Florida Institute of Phosphate Research.
The intent of the study was to determine whether wastewater stored on
phosphate mines could be treated by filtering it through wetlands and
sand piles on the mine sites and stored underground.
The study entailed sampling groundwater at 12 wells bored into the
ground on reclaimed mine sites. The samples yielded water that met
drinking water standards except for two minor factors, excessive iron
and manganese.
However, Schreuder said he found, in a 1994 study, that mine pits would
not serve well as reservoirs because the water would seep out of
the pits, just as Bacchus has theorized.
He said he also found, in a 2006 study, that the land actually drains
more water into the Peace River or its tributaries after it is mined
than before.
That's because the mining eliminates the pine trees and other vegetation
-- and that reduces the "evapotranspiration."
The natural ecosystem has a limited capacity to store water, Schreuder
said.
The Floridan aquifer also remains depleted due to continued agricultural
pumping, despite the fact that phosphate mining has reduced its
withdrawals from some 300 million gallons per day to about 80 mgd.
An above-ground reservoir could make up for those limitations,
Schreuder believes.
"We have a very seasonal flow of surface water, a lot in summer and
minimal in the spring," Schreuder pointed out. "You need to overcome
that by storing something somewhere."
You can e-mail Greg Martin at gmartin@sun-herald.com.
By GREG MARTIN
Staff Writer
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