A 130-acre tract of conservation land south of Boston remains largely open to public use without posted warnings despite new risks of unexploded munitions spelled out in a report to Massachusetts environmental officials more than three months ago, WGBH News investigative partner The Eye has learned.
The site in Hanover, on Boston’s South Shore, has more than four miles of walking trails on what was once a sprawling munitions factory and test range.
The walking trails, on what is known as the Fireworks Property, wind through woods along a river and across two ponds. The rural landscape appears pristine, but the soil and sediment in the water are both highly contaminated with mercury, lead, and solvents — a legacy of 60 years of military manufacturing there that ceased in 1970.
Townspeople have waited more than 20 years for a clean-up of the toxic mess.
A project to excavate and remove the potentially dangerous explosives at a cost of $542,000 was supposed to begin last November but has been delayed until spring even though the money is available to do the work.
In 2005, an assessment of the site submitted to the state Department of Environmental Protection detailed the pollution and also concluded that only one area of the Fireworks site posed a significant risk of harm due to potentially live ordnance. That area has been fenced off since at least 2005, with provisions for local authorities to monitor the fencing periodically.
But in a report submitted to the state on Oct. 16, environmental engineers at the clean-up firm Tetra Tech highlighted a second area on the site, formerly used as a test range, with potentially dangerous munitions and explosives. It’s unclear exactly where the test range is located on the site. The redacted report highlighting the possible dangers was released to The Eye under a public-records request.
Hanover Town Manager Troy Clarkson said the test range cited in the report lies in a very remote area of the Fireworks Property, and declined to provide further details.
Old But Dangerous?

“If I felt for one minute that there was any imminent or potential threat to the residents of this community, then we would be taking swift and decisive action,” Clarkson said.
Military-ordnance experts at the U.S. Army Corps of Engineers believe it’s critical to notify people when there’s unexploded ordnance in an area accessible to the public.
“The public should be made aware if there is an issue,” said David Larsen, a project manager at the Army Corps’ regional office in Concord. “Any ordnance or suspected ordnance you may find, however old, may still be very, very dangerous. You can go into civil war battlefields and dig up cannonballs, and they are just as dangerous today as the day they were fired.”
Roger Leary, a nearby resident and the founder of a social club that frequently hikes the Fireworks Property trails, said he’s unhappy the town hasn’t warned the public.
“If I worked for the town, I would certainly want to at least post at the trailheads — it’s crazy not to,” said Leary, 53, on a recent Thursday afternoon. “It would have been nice to know, because there are a few times I’ve gone off the trails. I’ll still hike down here, but I’ll be a little more vigilant.”
The Massachusetts State Police Bomb Squad met in mid-September with Hanover’s fire and police departments to discuss the project to remove unexploded ordnance from the site, according to a 10-page letter sent to the state in October from Tetra Tech, the engineering firm tasked with cleanup of the ordnance.
The objective of the work “is to achieve conditions posing no significant risk at the two sites by removing the surface and subsurface metal and debris, impacted soil, and any material potentially presenting an explosive hazard,” the letter stated.
At a meeting at town hall Jan. 9, some Hanover officials joked that maybe the ordnance cleanup should wait until summer. “Can we try to coordinate this around the 4th of July?” said John Barry, a member of the Fireworks Site Focus Committee, whose quip elicited laughter.