By Rogers Worthington
and Oscar Avila
Tribune Staff Writers
One of the most striking measures of the harsh, early winter of
2000 is the huge demand for de-icing chemicals to spread on area
roadways, the most popular being that ancient residue of dead
seas: salt, or sodium chloride.
But just as
winter has stalled road and rail transportation across the Midwest,
it has slowed the delivery of salt by truck or train. And salt-laden
barges destined for Chicago and other points are stranded at the
docks or trapped in the ice on the Mississippi and Illinois Rivers,
thanks to an early freeze.
"We can
still get barges to St. Louis, but beyond St. Louis it looks like
it is almost impossible right now," said Donald Ferguson,
general sales manager for Cargill Salt Co., which supplies about
50 percent of the road salt used in the Chicago area. Most of
that salt is shipped upriver from Louisiana.
U.S. Army
Corps of Engineers spokesmen described the Mississippi from St.
Paul to Rock Island, Ill., as a "500-mile skating rink."
Another major
supplier, IMC Salt Inc., is having trouble getting trucks down
to Chicago from its terminal at Jones Island in Milwaukee because
of structural cracks in the Hoan Bridge, which connects the island
to the mainland.
At the same
time, salt shippers are competing for trucks being used for the
more lucrative activity of snow hauling between storms.
Cargill's
fallback option, shipment by rail via Norfolk Southern Railroad,
is out because the railroad's own weather-related problems have
prompted it to opt out of its contract, Ferguson said.
With winter's
hardest edge moving to the East Coast, northeastern Illinois municipal
and transportation officials are hoping for a reprieve that will
give them time to replenish their salt stores. They have a safe
margin of reserve, but a heavy snowstorm or two could deplete
things quickly.
"This
is shaping up to be one of the top years ever for rock salt usage,"
said Richard Hanneman, president of the Salt Institute, an industry
group in Alexandria, Va.
The Chicago
region gets its salt from mines in Louisiana, Detroit, Cleveland,
Lansing, N.Y., and Ontario. All are working overtime, salt company
spokesmen said.
Salt from
the Canadian mines comes across the Great Lakes by ship. But if
the lakes freeze badly in January, trains will have to be used,
which could drive up costs, said Steven Briggs, vice president
of sales for IMC Salt in Kansas City, Mo.
Most Chicago
area municipalities can buy up to 130 percent of their salt supply's
contracted amount at the contracted price, which can run between
$26 and $30 a ton. But anything beyond that can be a seller's
market.
Transportation
officials have been searching for decades for an alternative to
rock salt.
Calcium chloride, which is drawn from natural brine deposits found
in porous sandstone formations, is often used with salt as a liquefying
agent. Salt needs moist snow to work, and it becomes inactive
below 20 degrees; calcium chloride produces its own heat, and
works down to 25 degrees below zero. But calcium chloride is more
expensive than salt. A 50-pound bag retails for $15 to $20, while
a similar bag of salt sells for $4 to $5.
A handful
of states with less snowfall and slightly warmer temperatures,
such as Oregon, have stopped using rock salt in favor of calcium
magnesium acetate, an organic product that is applied before icing
conditions occur.
A cheaper
solution is to mix salt 50-50 with "birdseye," a coarse
sand. "It's not a preferable situation," said Al Giertych,
Lake County assistant engineer. "It can be quite messy and
has to be cleaned up after the winter is over."
The short-term
shortage notwithstanding, salt supplies are virtually inexhaustible,
Hanneman said.
Most salt
mines are found in sedimentary layers 1,000 to 2,000 feet deep,
left behind by long-vanished seas. Others, such as those in Louisiana,
are domelike formations deep underground, pushed up by the Earth's
core.
Because salt
used on roadways drains off into lakes and rivers and back into
the oceans, the supply is constantly recycled, he said. But that
same process raises another concern: Chloride from the salt has
the potential to contaminate roadside land, storm drains and other
water supplies.
An official
with the Illinois Environmental Protection Agency's water pollution
permit section said water monitoring has found no evidence that
rock salt has damaged main streams or rivers. Occasionally, however,
chemicals have been found in local puddles and ponds.
Still, researchers
hope to promote de-icing solutions made from biodegradable products.
St. Charles, in Kane County, has experimented for three years
with a solution called IceBeeter -- made from fermented beet byproducts
-- that is mixed with rock salt.
The solution
speeds the melting process, allowing the city to use less rock
salt, which results in less chemical residue, street foreman Ben
Deutsch said. But IceBeeter isn't cheap either.
Shang-Tian
Yang, a professor of chemical engineering at Ohio State University
and author of a Federal Highway Administration study on alternatives
to rock salt, said municipalities aren't looking at the big picture.
Even with higher prices, alternative treatments would save money
because they cause less corrosion to vehicles and less damage
to the environment, Yang said.
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