It’s a dirty job, and the Navy has to do it.
The task: cleaning up the former home of the South Weymouth Naval Air Station, a property with a history dating back to World War II. In the 1940s, blimps that silently patrolled the US coast were housed in giant hangars at the air base. Later, modern jets roared down its paved runways.
Decades of military use left behind petroleum, heavy metals, and volatile organic compounds that settled into the ground water and soil on certain parts of the base. Trash and debris were dumped in three landfills on the edges of the property. All of that contamination earned it a spot on the Environmental Protection Agency’s National Priorities List in 1994. Although most of the base is considered clean today, the property as a whole is still deemed a Superfund site.
The airfield closed in 1997, and over the years tons of contaminated soil have been hauled away, dozens of underground oil storage tanks have been dug up, and soil, sediment, and ground-water samples have been tested and retested. Renamed SouthField, the old base is being developed into a mixed-use community within the communities of Abington, Rockland, and Weymouth that could eventually encompass up to 2,855 homes, as well as shops, offices, and a golf course.
So far, the Navy has spent approximately $66 million on site investigation and cleanup efforts, and it will cost about $25 million to finish the job, according to David Barney, the Navy’s Base Realignment and Closure environmental coordinator for the South Weymouth Naval Air Station.
The Navy has examined more than 150 areas of the base that were suspected to be contaminated. All of those sites have been addressed, and 11 continue to be investigated or are in the “remedial action phase,” said Barney.
Keeping tabs on these efforts is the South Weymouth Naval Air Station Restoration Advisory Board, a group of government officials and community representatives who hold regular meetings to update the public about the cleanup.
Dominic Galluzzo, a Weymouth resident who has been attending the meetings for the past nine years, said he believes the government is doing what needs to be done. He said he knows first-hand the careful planning and testing involved, and has seen the Navy invest a lot of time into the cleanup.
“I feel the Navy is doing its best to adhere to its responsibilities,” he said.
The Navy’s cleanup efforts will continue through 2016, and some areas will continue to be monitored for decades.
“We expect the final remedy to be in place by 2016, and then the [National Priority List] delisting process can begin,” said Carol Keating, the EPA’s remedial project manager for the site. “It’s hard to say when the actual delisting will take place.”
The contaminants found at South Weymouth are commonly found at other military installations, according to EPA officials. Most of the land has already been deemed clean enough to transfer ownership from the Navy. To date, the Navy has transferred more than 1,280 acres, with 146 acres remaining, according to Barney.
As section chief for the EPA’s federal facilities Superfund program, Bryan Olson oversees Superfund cleanups at Department of Defense properties all over New England. He said this is not the biggest — or the most expensive — Superfund site cleanup in the region. The project at the Massachusetts Military Reservation, a much larger property on Cape Cod that includes Otis Air National Guard Base/Camp Edwards, for example, is far more complex, he said.
“It’s a very important site for us, because of the reuse,” said Olson of the old Weymouth base. “We naturally want to make sure it’s safe to reuse and we get it cleaned up.”
Olson said the cleanup is progressing as scheduled.
“We always want to do things faster, but especially over the last few years it has been progressing well,” said Olson. “The challenge is weaving the development in with the cleanup. Protecting public health is the priority at these sites. We try hard to integrate the cleanup with the development. It’s not easy.”
Cleanup efforts have focused on the following areas (see map on Page 1):
Solvent release area
This covers 8 mostly undeveloped acres south of Pidgeon Road, and was previously found to be contaminated with volatile organic compounds, primarily tetrachloroethene, a toxic chemical used in dry-cleaning fabrics and metal degreasing, and considered by the EPA to be likely carcinogenic to humans. The proposed cleanup plan includes installing two underground porous barriers that will help treat the polluted ground water. It also calls for injecting a compound into the ground that will help break down the contaminants. (The Navy will accept written comments on the plan until March 23. Written comments can be sent to email@example.com or mailed to Brian Helland, Remedial Project Manager, BRAC PMO, Northeast, 4911 South Broad St., Philadelphia, PA 19112.)
Sewage treatment plant
Another area of the base that is being examined is where a sewage treatment plant operated from 1953 to 1978. A chemical called dieldrin was found in the surface soil, arsenic was found in the ground water, and PCB in surface water. Contaminated soil was excavated, but then additional petroleum and solvents were detected. “They encountered more contamination than they estimated,” said Keating. “They’re doing additional sampling there.”
Three closed landfills
The West Gate Landfill was capped in the summer of 2011, and the so-called “Small Landfill” was capped in summer 2010. PCB-impacted soil was removed from the “Rubble Disposal Area,” which was covered with a vegetated soil cap.
Firefighter training areas
At one time, 500 to 1,500 gallons of fuel per month were burned during firefighting exercises at the base. Petroleum-soaked soils were removed from the site. Chemicals found in firefighting foam have been detected in the ground water.
Tile leach field
This area is about a third of an acre, adjacent to French Stream, that was used for disposal of sanitary wastes from 1945 to the early 1950s. Studies of the soil and ground water found that risks did not exceed regulatory thresholds. In May 2006 the EPA and the Navy concluded that no further action was necessary at the site.
The so-called “Abandoned Bladder Tank Fuel Storage Area” is where four 10,000-gallon tanks that were used to store aviation gasoline were removed in 1987.
Industrial operations area
This encompasses the power plant, maintenance facilities, building shops, and water tower in the central area of the base. The Navy has sampled the soil and found no ground-water issues. Several places need to be excavated because PCBs were found, and planning is underway to remove soil.
This hangar is located near the center of the base. It was built in 1956 and used as an aircraft storage and maintenance facility. Elevated trichloroethylene (TCE) concentrations in ground water were detected to the south and southeast of the site. (TCE is an industrial solvent used to degrease machinery and has been linked to higher risks of Parkinson’s disease and certain cancers.) The cleanup plan includes chemical oxidation and injection of a material into the ground to enhance the biodegradation of volatile organic compounds. EPA officials estimate that the site will be clean in five to seven years.
The Marine Air Reserve Training Building is gone, and all that is left is a concrete slab. A feasibility study is being finalized and a proposed cleanup plan should be ready for public review this summer.
A public meeting on Building 81 is expected to take place in July.The next Restoration Advisory Board meeting is scheduled for May 9 at 7 p.m. at the New England Wildlife Center at 500 Columbian St. in Weymouth.
Emily Sweeney can be reached at firstname.lastname@example.org. Follow her on Twitter @emilysweeney.