BANGOR, Maine — After nearly a decade of study and legal wrangling, the city is set to begin removing deposits of coal tar — a known carcinogen — from the Penobscot River.
A crew from a Wisconsin environmental consulting and engineering firm already has begun prep work this week, drilling into the riverbed to create an apparatus that will keep fish away from the site. As soon as the American Folk Festival wraps up this weekend, the crew will resume work with the hope of finishing in November.
The exhaustive cleanup project is expected to cost about $7 million, which will be paid for by settlement money from Citizens Communications Co., a group of third parties a judge ruled was responsible for most of the cost. Any additional cost will be paid by the city through its downtown tax increment financing district funds.
“The issue of coal tar is long-standing, going back literally decades, so certainly getting this done is a major step forward,” City Manager Edward Barrett said Thursday.
Initial studies done by the city early in this decade determined that Bangor Gas Works, which operated from 1881 to 1963 on land where the Main Street Shaw’s Supermarket is now, was the source of the coal tar. The substance is a byproduct of gas manufacturing and likely was deposited in the river through a sewage outlet that began at the gas plant.
For most of the year, coal tar is not really a problem, but when the water warms in August, the deposits rise to the surface in small blobs that stick to objects such as boats and animals. When absorbed through skin, coal tar is known to cause cancer.
City Engineer Jim Ring, who has worked closely with the Wisconsin firm RMT Inc., and with state and federal regulatory agencies, said the cleanup project is unique.
Once the contractor resumes work next week, it will erect a containment curtain on 1.3 acres of riverbed to disrupt the ecosystem as little as possible. Then, roughly 6,000 cubic yards of contaminated sediment will be removed and trucked to a landfill. Next, the firm will construct a sloped stone cap that will divert any additional coal tar away from the river to the shore, where it is no longer problematic.
During the remediation, Ring cautioned, the initial dredging will produce some foul odors throughout that part of the city. He said those odors would be monitored closely but are unavoidable.
The legal battle over the coal tar contamination began in 2002 when the city sued the Stamford, Conn.-based Citizens Communications, the successor of a series of corporate entities that owned and operated Bangor Gas Works. Citizens denied it was responsible for the pollution in the section of the river known as Dunnett’s Cove. The company in turn sued a dozen companies alleging that others, including the city, should pay for the cleanup because they, not Citizens, were responsible for the plume-shaped coal-tar deposit. Some of those companies then sued fourth parties.
In July 2008, a federal judge ruled that Citizens must pay about $7 million toward the cleanup. However, the group could still pursue claims against Barrett Paving Materials Inc., Dead River Co., Honeywell International Inc. and others to recoup some of that total. Barrett said that process is ongoing, but last summer’s settlement allowed the city to move forward with the cleanup.
With all the improvements to the city’s waterfront area, Barrett said, the timing is right.
“As we continue remaking our waterfront and attracting private development down there, it certainly benefits us to have this done,” he said.