detected in waterways
Experts call for careful removal of chemical
By Gene Schabath
The Detroit News
TRENTON -- More than 3 million cubic yards of cancer-causing
PCBs remain in the sediment in Metro Detroit and southeast
Michigan waterways, and it could take as much as $100
million to remove the contaminants, according to a report
prepared by more than 50 scientists and researchers from
the United States and Canada.
Despite the new findings, no one is believed to have
died from the chemical, and the risk to humans is considered
low, said Thomas M. Heidtke, one of the 50 scientists
and one of two who compiled the group's findings for the
report, published in April by the U.S. Environmental Protection
The PCBs would be a more serious health risk to humans,
fish, birds and the environment if they were disturbed
by events such as a massive storm, Heidtke said.
"We had a once-in-300-years storm about 15 years
ago that spread PCBs (from the land) all over southern
Saginaw Bay," said scientist John Hartig, another
of the 50 researchers who worked on the study. "We
need to clean up (Metro Detroit PCB hot spots) before
we have a big storm event like that in our area."
Dredging is less of a concern when it comes to PCBs,
he added. "We have a number of new technologies that
are far superior to the old way of dredging. (State and
federal environmental agencies) won't allow those old
methods to be used anymore."
If removed, the amount of PCBs would cover Belle Isle
with 2 feet of the contaminated sediment, scientists said.
Polychlorinated biphenyl, more commonly called PCB, was
banned by the federal government in 1977 because it posed
a health threat.
The Detroit River, Rouge River and River Raisin near
Monroe are considered major "hot spots" for
PCBs among the 50 scientists and technical experts involved
in the study, funded by the EPA, Hartig said. The Trenton
Channel in the Detroit River is considered the worst.
The largest potential for harm is in fish that Metro
Detroiters consume from tainted waterways. For now, the
risk is low.
"We're not talking about a significant increase
in the risk of cancer," said Heidtke, an associate
professor with the Department of Civil and Environmental
Engineering at Wayne State University. "But if for
any reason those sediments in the hot spots are disturbed,
there could be a significant release of PCBs in the ecosystem.
That has the potential to raise the levels of PCBs in
birds, fish and people.
Falling water levels on the Great Lakes also are a concern
and also disturb PCBs in bottom sediments, said Hartig,
river navigator for the Greater Detroit American Heritage
River Initiative, a program aimed at improving the Detroit
"When a big freighter goes through the Rouge River,
which is one of our hot spots, it will stir up those sediments,"
Cleanup of waterways in Metro Detroit and southeast Michigan
during the last 30 years, and the PCB ban, significantly
lowered PCB levels in local walleye, Heidtke said. But
carp, drum or suckers, fish that feed on the bottom of
lakes and rivers and may live in a hot spot because they
tend to stay in one area, are more dangerous because they
tend to have much higher concentrations of PCBs.
"Those fish are consumed," even though people
aren't supposed to eat the fish, Heidtke said.
Researchers concluded in the 130-page report that the
solution to the problem is to remove the PCBs by dredging.
"They have to do what they did in St. Clair Shores,"
The Lange and Revere street canals near 10 Mile and Jefferson
were the site of a $6 million EPA cleanup to remove PCBs
above 10 parts per million from July 29, 2002, to March
The project involved the excavation and disposal of 23,000
tons of contaminated sediment from the mile-long 10 Mile
Drain storm sewer system and two canals totaling about
1,600 feet, said Tom Skinner, an EPA administrator.
High-concentration PCB materials were sent to Wayne Disposal
in Belleville and nonhazardous materials went to a landfill
in Lenox Township, Skinner said.
About $130 million has been spent in the last 10 years
removing PCBs from area rivers, lakes and other waterways
in Southeast Michigan, Hartig said. The most expensive
project was the dredging of the Willow Run Creek in the
Ypsilanti area of the Huron River. It cost $70 million
to remove more than 330,000 cubic yards of sediment tainted
Hartig, an adjunct professor of civil and environmental
engineering at Wayne State University, estimates it will
cost about $100 million to purge the 3 million cubic yards
of PCBs from area waterways.
Without the cleanup, scientists fear the PCBs eventually
could become a problem.