Great Lakes Region 'Zaps' Pollution
In the heavily traveled Great Lakes region
of the Midwestern United States, polluted harbors are among
the biggest threats to water quality. Over the years, experts
have identified many harbor sites contaminated by leaked
fuels, bilge waste or spilled toxins. But cleanup has been
painfully slow, difficult and expensive.
Now, some people in Duluth, Minnesota,
are taking a new approach. They're using electrical energy
to clean up pollutants. Supporters of the technology,
which is now getting its first American tests, say it's
cheaper and faster than conventional clean-up methods.
Duluth's Stryker Bay is a lovely little cove
alongside the St. Louis River. The bay's quiet, shallow
waters teem with ducks in the summer. A tree-shaded hiking
path traces its shoreline.
Tim Leland lives along the shore. From
his home, he sees waterfowl, and he sees fouled water.
"Stryker Bay is a shallow bay. It's six feet
(two meters), at the most, of water," he says. "But there's
a silt that's underneath it, and all this tar and stuff
that's coming up. Summertime we do have a lot of oil that
comes up to the surface." The bottom of Stryker Bay is a
biological time bomb. Under the sand are pools of oily stuff
that experts call polynuclear aromatic-hydrocarbons, or
PAH's. For nearly a century, Stryker Bay was an industrial
sewer. PAH's were first identified under the bay in the
1970s. They're still there. There's not enough money to
pay for their removal, and even less agreement on exactly
how to get rid of them.
But what if you could make pollution
go away by throwing a switch? That's essentially what
ElectroChemical Processes, L.L.C., a German-based company,
promises. And U.S. officials are listening.
The first underwater test in the United States
of the firm's so-called Electrochemical-GeoOxidation treatment
is underway in Duluth. And early results are encouraging.
It's a simple concept, according to Ken Whittle with U.S.
licensee Electro Petroleum Inc. Whittle describes the process
underway behind him in a pair of water-filled pits.
"I think it's a pretty simple kind of
thing," he says. "If you want to look at it: if you have
a battery charger at home, you plug the battery charger
in, you take the two leads so you connect them to the
terminals on the battery. Well, that's pretty analogous
to what's going on here."
Each pit is filled with polluted mud and
covered with water. Metal pipes are sunk into the muck.
In one pit, a carefully controlled electrical charge pushes
electrons through the sediment between the pipes. It's supposed
to break the electron bonds of dangerous molecules, like
PAH's. What's left is harmless, like carbon and water.
The test is being financed by the Environmental
Protection Agency and the U.S. Army Corps of Engineers,
the agency responsible for dredging shipping lanes. Dealing
with polluted sediment is a huge expense, according to
Army Corps researcher Tommy Myers.
"It's a real big problem for us to dispose
of that material. We can't put it back into the water,"
he says. "And, typically, we confine it in what we call
a confined disposal facility, and just store the material
in perpetuity and let it break down through natural processes,
if it will."
Officials would rather destroy pollutants
than store them. But conventional methods are expensive,
smelly, and noisy. And they all require dredging.
"In this particular technology, it wouldn't
necessarily require dredging," says Mr. Myers. "There's
very little noise or gaseous emissions associated with
it. The main thing is it could be applied in situ; that
means in the water, without having to dredge."
Proponents say Electrochemical-Geo-Oxidation
is a bargain. Pollution officials estimate that using
conventional methods to clean up polluted sediment in
Stryker Bay would cost about $260 per cubic meter. David
Bowman, of the Army Corps of Engineers in Detroit, says
electrical cleanup would cost a quarter of that.
"Our goal with this project was to find
a technology that would work for around $100 a cubic yard
(or about $130 per cubic meter)," he says. "The vendor
talked about that they might be able to treat material
for around $45-$50 per cubic yard (or about $60-$65 per
cubic meter) at Duluth Harbor."
The contractor also claims the process works
fast. A typical site can be cleaned in just a few months.
In the Duluth test, PAH's have decreased by 45 percent in
about a month. That's promising, although far from conclusive.
The process won't get every molecule, but it's intended
to reduce contaminants below dangerous levels.
It's also supposed to work on toxic metals,
like mercury, which can be drawn to the electrodes. Even
radioactive isotopes can be collected, according to the
The test begun in Duluth this summer
is winding down with the early arrival of cold weather.
Final results won't be published for several months. Meanwhile,
the company has set up a second demonstration, under the
waters of Washington State's Puget Sound, one of the nation's