St. Clair ShoresDecember 23, 2013
Interim cleanup plan in the works for 10 Mile Drain
By Kristyne E. Demske
C & G Staff Writer
In an effort to stop contamination before it continues down the 10 Mile Drain, the U.S. Environmental Protection Agency was back in the city Dec. 5 to share with residents a proposal for an interim cleanup plan.
Polychlorinated biphenyls (PCBs) were first found in the 10 Mile Drain system in 2001, and now, EPA Remedial Project Manager Colleen Moynihan spoke to city residents at an open house and public meeting night to explain what the EPA wants to do while a full-site cleanup plan is developed.
The agency has been investigating the entire 10 Mile Drain system, which contains 250 manholes, checking for contamination in the area of Bon Brae Street to 10 Mile Road and Harper Avenue to Jefferson.
Consistently, the investigation has found contamination levels higher near Bon Brae and Harper Avenue that decrease as the pipes move toward Jefferson Avenue. EPA officials say this means that the absorbent snares in the 17 weirs placed 2010 on Harper at Bon Brae — and east down Bon Brae toward Lake St. Clair — are catching PCBs before they hit the Lange and Revere streets canal and the lake.
The EPA considers nine criteria when looking at cleanup plans: overall protectiveness of human health and the environment, compliance with applicable requirements, long-term effectiveness and permanence, reduction of toxicity, mobility or volume of contaminants, short-term effectiveness, implementability, cost, state agency acceptance, and community acceptance.
It developed several alternative interim cleanup proposals, ranging in cost from $0 for no action up to $5.2 million for a proposal to excavate, clean up and replace the four manhole vaults that have been found to have the highest levels of contamination. Two of those vaults are near the intersection of Bon Brae Street and Harper Avenue, and the other two are farther east down Bon Brae. Before new manhole vaults were installed, a flexible synthetic liner would be installed to separate the existing soil from the new clean bedding and backfill.
Using the criteria, Alternative 7 was the option recommended by the EPA. It calls for the excavation, cleanup and replacement of the two vaulted manholes located at the intersection of Bon Brae Street and Harper Avenue. Those are the two most contaminated manhole vaults the EPA has been monitoring. The total cost of the proposal is $3.9 million and would take about six weeks to construct.
“We believe it is the best-balanced of all the alternatives,” Moynihan said. “We believe that’s the cause for the contamination of the other two” contaminated manhole vaults farther down Bon Brae Street. By taking out the two most contaminated manhole vaults and the surrounding backfill, the EPA hopes “to remove the major source from the system.”
“We know there’s oil inside the pipe,” Moynihan continued. “We’ll remove the major source by removing these two vault systems.”
Moynihan said the public is welcome to comment on the plan until Jan. 6 by sending an email to email@example.com or filling out the public comment form at www.epa.gov/region5/cleanup/tenmiledrain. The interim cleanup plan should be finalized by March, Moynihan said, and that’s when they will request money to pay for the plan from the federal government.
While the funding request is pending, the EPA will work on the engineering design of the selected plan in an attempt to implement construction of the project by 2015.
Also ongoing during that time, Moynihan said, would be a feasibility study to determine cleanup options for the entire site, which they hope to have proposed by the end of 2014.
“What we do know is where the oil’s resting now,” she said. “We want to tackle and manage the source before we do cleanup on the sediment.”
During the course of 2013, the EPA removed 12 55-gallon drums of contamination from manhole vaults in the 10 Mile Drain.
“We’re tackling all these things in parallel,” she said.
Courtney Gregory, of St. Clair Shores, lives on Bayview Street. Although his isn’t one of the canals affected by the contamination, he came to the Dec. 5 open house to learn more about the EPA’s plan because he wants his canal tested, too.
“What we’re concerned about is having our canal tested (because) three or four people on our street died of cancer,” he said. “It’s never been addressed, that I know of … why it’s just being concentrated there?”
Peter McInnes is a member of the Macomb Conservation District. As such, he said, the group is very concerned with the EPA’s actions as they relate to water quality in Lake St. Clair.
“This is not a simple problem,” he said. “We’ve got a lot of smart people working on this. The Lange canal — that’s not where the problem is. The people want their canal cleaned out.”
Moynihan said they expect to return to the area in the spring to give another update.