The United States Navy is set to open a public comment period on its proposed remedial action plan for Noman’s island— a 600-acre dot off the coast of Chilmark that was used as a naval gunnery range and aerial bombardment site for much of the 20th century.

Although bombing operations ceased in 1996 and the island has since been turned into an unmanned wildlife refuge, Noman’s still contains nearly a half century of unexploded ordnance. That ordnance, according to the Navy, continues to pose a significant safety risk to the public.

In a plan released on August 28, the Navy has opted to forego removing the remaining ordnance because public access to the island is already restricted, instead proposing to engage in a heightened public awareness campaign about the island’s safety risks. The public awareness campaign includes increased signs and pamphleting, as well as strict enforcement of trespassing and land-use violations.

“Based on a series of site risk and safety assessments and prior remedial actions, that addressed potential chemical contamination, it was determined the site no longer poses a significant risk to human health, public welfare, and the environment, given the identified future use of the island as an unstaffed national wildlife refuge,” the remedial action report states. “However, the assessment of risk to public safety revealed that a potential explosives safety concern exists due to the presence of residual unexploded ordnance (UXO) on the island.”

The report states that if the Navy were to attempt a removal of all of the island’s unexploded ordnance, “a significant loss of habitat would occur.” The island is currently under the ownership and purview of the U.S. Fish and Wildlife Service, serving primarily as a wildlife refuge for migratory birds, among other species.

The USFWS announced last year that it would be releasing a small population of endangered cottontail rabbits on the island in an effort to reestablish their population. The rabbits were transplanted from Cape Cod.

Before the war years, the island was used as a stopping-off point for rum-runners, according to legend, as well as codfishermen, who needed a space to salt and dry their catch. Small fishing shacks that used to line the shore are now mostly gone.

By 1943, the Navy had begun using the island as part of its aerial target practice regiment, which occurred on other less-inhabited spots across the Island, like Aquinnah and Cape Pogue. Live air-to-surface bombings occurred regularly at three specific target sites on Noman’s until 1996, with naval bombing and training operations managed from Naval Air Station South Weymouth.

In 1998, the Navy removed all surface-level ordnance on the site — although the report states that buried or newly exposed ordnance continues to pose a health risk.

The island is part of the town of Chilmark and is topographically similar to the Vineyard, with steep cliffs along its southern shoreline and sandy beaches along its north side. Two small ponds, home to a large population of turtles, dot the island’s marshy shrubland interior.

In more recent years, human contact with the island has become rare. The island officially became a wildlife refuge in 1998, and field officers with the USFWS conduct one to four yearly site visits to the island, according to the report. Since the beginning of the remedial action program, when the island came under USFWS ownership in 1997, there has been scant evidence of trespassing, according to the report.

But the report further says that should the proposed use of the island change, such as allowing the construction of residences, public access or other forms of development, it may be appropriate to take further action to remove the unexploded ordnance. For now, the Navy has proposed that the island remain as it currently stands.

“The selected remedial alternative of institutional controls/public awareness and enforcement was judged to be the best option for meeting the safety-related remedial goals,” the report states.

Public comment on the proposal is open from Sept. 15 through Oct. 14. Comments can be emailed to david.a.barney@navy.mil. A virtual public hearing on the proposed remedial action has been scheduled for Sept. 29 at 7 p.m.