Out & About with the Casco Baykeeper May 2016

Posted on May 12, 2016

Out and About with Ivy Header

Portland Gas Works circa 1930

Portland Gas Works circa 1930

Sometimes as I idle at yet another stop light, I wonder how charming 19th century Portland must have been. Then I think about the remnants from Portland’s industrial past that we are still cleaning up.

From 1852 to 1965, the Portland Gas Light Company, located on the waterfront in the city’s West End, turned coal into gas to light street lamps and heat homes around the region. The process created by-products of coke, coal tar, creosote, sulfur, and ammonia. The stench of rotten eggs permeated the air.

In 1965, an interstate natural gas pipeline arrived in Portland, replacing the need for local coal gasification. The plant closed a year later, and Northern Utilities was formed from the merger of Portland Gas and the Lewiston Gas Light Company. In 2008, the company was acquired by Unitil, which provides electric and gas distribution services throughout New England.

Unitil inherited the by-products of the coal gas era: contaminated soil, mounds of wood chips caked in coal tar, and liquid coal tar seeping into the Fore River from underground. Unitil also inherited the responsibility of cleaning up the site. Unitil and the Maine Department of Environmental Protection (DEP) came up with a remediation plan that involved excavating contaminated soil, gravel, and wood chips, capping the seepage area, and building a watertight wall around the seaward end of the property.

In mid-March, I walked the Unitil site with the engineer who led the remediation efforts. I reviewed the remediation plans and saw the clean, sheen-free water in the Fore River. I walked along the riprap and saw the cap that prevents further oil products from reaching the water. All of the contaminated wood chips have been removed, and the soils have tested clean.

In December, DEP awarded Unitil a certificate of completion, certifying that the company had succeeded in cleaning up an environmental mess that it inherited from past land use.

I think about other waterfront owners who are facing a dilemma not unlike Unitil’s situation. Portland’s private wharf owners also may have to remove contaminated material not of their making, if they choose to dredge around their piers and wharves. Even though they didn’t dump the sediments under their wharves, Portland’s private wharf owners have to pay to remove the toxic sediments. The cost of relocating contaminated dredge spoils can be prohibitive. Leaving toxic mud where it lies is bad for the lobsters, crabs, and clams that dwell beneath the wharves—and bad for the working waterfront. Disposing of contaminated spoils elsewhere makes sense only if this will create better environmental conditions than we now have. We are working with city officials and waterfront business owners to find a feasible solution.