BRUNSWICK — After nearly 70 years as a military base, there are several significant environmental concerns being cleaned up at the former Brunswick Naval Air Station (now known as Brunswick Landing).

“It’s been a military institution for almost 70 years and part of that type of operation is there’s always some sort of environmental contaminants (involved),” said Steve Levesque, Mid-Coast Regional Redevelopment Authority (MRRA). “It’s common in all military institutions and big industrial sites. Disposal methods in the 1940s, 50s and 60s were a lot different than after that.”

According to Paul Burgio, Base Realignment and Closure (BRAC) environmental coordinator, the U.S. Navy is actively addressing all of the environmental problems on the base in order to convey the land to MRRA.

In order for the land to be transferred by the Navy to MRRA for redevelopment, all environmental contaminants, including things like pesticides, fuel solvents and old land fill sites, must be removed from the property and the land parcels must be signed off on by the Maine Department of Environmental Protection and the Environmental Protection Agency.

“The Navy continues to work very closely with the Environmental Protection Agency Region I and the Maine Department of Environmental Protection on accelerating the cleanup of all environmental sites, in order to make property available for reuse and development,” said Burgio.

The major, but not only, environmental concern at the base is the contamination of groundwater by Eastern Plume, a contaminant that appears as a result of outdated solvent disposal practices.

“The Navy has actively planned and budgeted for addressing all of the environmental sites at the former Naval Air Station Brunswick property,” said Burgio. “The Eastern Plume, which is groundwater plume containing low levels of solvents, is the most challenging site on the base, but is actively being remediated by the groundwater treatment plant.”

Claudia Sait, federal facilities project manager for the Maine Department of Environmental Protection, said that a groundwater contaminant such as Eastern Plume is much more difficult to clear away than something that has soaked into the soil.

“The most difficult, in general, is when it gets into groundwater,” she said. “When you have soil, you can sample for (contaminants) but when it gets into groundwater, you can’t pull it back. It takes time and we usually put restrictions on use of groundwater so that no one is exposed.”

She said that land control methods such as fences are being used to ensure that no one is exposed to known contaminants. No known contaminants on the property will cause harm to humans, unless water is ingested, she also said.

The Navy is handling the all of the clean up work while the Maine Department of Environmental Protection and Environmental Protection Agency provide oversight.

In addition to the clean up of Eastern Plume and other toxins on the base, in April of 2012, the Navy released the Historical Radiological Assessment for the property and “will continue to work with the regulatory agencies to address any radiological material found on at the former base,” said Burgio.

There is no concrete time line for when all of the property on the former Naval Base will be transferred to MRRA, but a significant amount of the land has already been conveyed to the redevelopment group.

“Over 55 percent (1,888 acres) of the land and facilities have been transferred to MRRA within the first year of base closure,” said Burgio.

Levesque said that MRRA will continue to develop the land on the base as it comes in. When all is said and done, around 2,000 acres will be transferred to MRRA and the remaining 1,200 acres will be divided between the town of Brunswick and Bowdoin College for development.

“A vast majority of (the land has been conveyed to MRRA),” said Levesque. “Compared to some other bases that’s significant. I think we’re significantly ahead of most other (BRAC) properties.”

Amber Cronin can be reached at acronin@theforecaster.net or 781-3661 ext. 125. Follow her on Twitter @croninamber.