A legal settlement has removed one of the remaining obstacles blocking an expanded natural gas pipeline through Otis State Forest in Sandisfield.

Tennessee Gas Pipeline Co., a subsidiary of the energy giant Kinder Morgan, has agreed to pay $640,000 to settle its lawsuit against the state for an easement through the state forest as part of its $87 million Connecticut Expansion Project.

But the agreement also requires Tennessee Gas to pay a similar amount for environmental monitors and remedies.

That brings the total value of the settlement to more than $1.2 million, according to a joint announcement on Thursday by Attorney General Maura Healey and Energy and Environmental Affairs Secretary Matthew Beaton.

Tennessee Gas had taken the site, including 400-year-old woodlands, by eminent domain. The settlement also includes recreational upgrades and replacement land for state conservation.

"This settlement sets a very high bar for the value of conservation land taken by eminent domain in Massachusetts," said Healey in a prepared statement.

"We are pleased that this settlement requires Tennessee Gas to provide important mitigation relief during the construction of the project and assure no net loss of critical conservation land in the area," Healey commented.

"The financial mitigation package that the Commonwealth will receive represents the tireless work of the state to ensure that the taking of conservation land through eminent domain is placed at an extremely high value," Beaton added.

The settlement allows the state "to acquire additional land for future preservation that will truly benefit generations of people within the Berkshire County region and beyond," he asserted.

Details of the agreement include:

— A payment of $300,000 by Tennessee Gas for the state Department of Conservation and Recreation (DCR) to identify and acquire additional conservation land in the vicinity of Otis State Forest that provides equivalent ecological benefits to the land affected by the pipeline expansion.

— An additional $300,000 for environmental protection and improvements to Otis State Forest, including $60,000 to be used by the state for recreational enhancements.

— And $40,000 for the fair market value of pipeline easements.

A leading pipeline opponent found fault with the settlement.

"While we like to think of the attorney general as 'the people's lawyer,' her office made clear to us early on that they considered DCR to be their client in this case," said Kathryn R. Eiseman, director of the Massachusetts Pipeline Awareness Network.

"DCR's marching orders from [Gov.] Charlie Baker seem to be that his energy combo platter is more important than our constitution and the natural treasures of our Commonwealth," she added.

Eiseman, who's also president of the Pipe Line Awareness Network for the Northeast, noted that the group's appeal of the state Department of Environmental Protection's water quality permit for the project is slated for a hearing on Jan. 10 at the U.S. First Circuit Court of Appeals in Boston. Another hearing on the appeal is set for Jan. 18 at the DEP. No construction can begin until the appeals are resolved, she said.

Also, the Army Corps of Engineers has yet to issue a permit under the U.S. Clean Water Act, and federal regulators have raised concerns involving historical preservation of ancient stone monuments and potential issues involving the Stockbridge-Munsee Community Band of Mohican Indians, who may not have been sufficiently included in other tribal consultations.

The Connecticut Expansion Project, approved last March by federal regulators, includes four miles of new pipeline in Sandisfield, with close to two miles of it in Otis State Forest, alongside two existing Tennessee Gas underground pipelines. Other loops of the 14-mile project are near Bethlehem, N.Y., and from Agawam into northern Hartford County.

The additional natural gas would serve three distributors in Connecticut.

The old-growth woodlands in Otis State Forest are managed by the state Department of Conservation and Recreation following a $5.2 million state purchase 10 years ago. Incursions on conserved land are protected by Article 97 of the Massachusetts Constitution.

The DCR had identified the area as one of the most significant land protection opportunities for the state. The acquisition was to protect land that contains a 400-year old Eastern Hemlock forest, rare plant and animal species, historical sites, rolling meadows and the 62-acre Lower Spectacle Pond.

"The idea that the land can simply be replaced with another acquisition is extremely troubling," Eiseman asserted. "This protected land is not fungible. It was protected for a reason."

The legal standoff settled by the state on Thursday began last May, when Berkshire Superior Court Judge John Agostini granted to Tennessee Gas temporary construction easements for construction and a permanent, six-acre pipeline easement through Otis State Forest by eminent domain, as authorized by the federal Natural Gas Act.

But the Massachusetts Constitution's Article 97 requires state lawmakers to approve any easement through protected conservation land.

After the legislature failed to act, Tennessee Gas took the land through eminent domain.

The Berkshire Superior Court decision in favor of the company — strongly opposed at the time by the state attorney general's office — was based on Agostini's finding that the U.S. Natural Gas Act overrides the state constitution's land protection article.

Reach contributor Clarence Fanto at cfanto@yahoo.com or 413-637-2551.