The federal government has reached final agreements with landowners to purchase 1,400 acres at the Flight 93 crash site in southwestern Pennsylvania yesterday, clearing the way for construction to begin on the 9/11 memorial park this fall.

The announcement means the government will not invoke eminent domain to seize the land, a prospect that was raised in the spring.

"The fields of western Pennsylvania, where the heroes of Flight 93 perished, are hallowed ground for a grateful nation," Interior Secretary Ken Salazar said at a news conference announcing the deal.

"Thanks to the collaborative efforts of the landowners, the Families of Flight 93 and the employees of the National Park Service, we have reached this important milestone in properly honoring the courage and sacrifice of the men and women who gave their lives that day."

Salazar said the property owners would be paid a total of $9.5 million.

Negotiations between the Park Service and the property owners, which had dragged on for years, got a jumpstart this spring when Salazar and Sen. Arlen Specter (D., Pa.) traveled to Somerset County to meet with landowners and family members of the 40 passengers and crew aboard the ill-fated plane.

Salazar delayed earlier plans to condemn the properties and continued negotiations, concluding agreements with seven of the eight property owners. The final property owner, Svonavec Inc., which owns most of the land where the plane crashed as part of its 275-acre parcel, reached agreement with the Park Service in January to allow the court to establish fair compensation for the property.

The Park Service said it expected the U.S. Department of Justice to file court documents for the Svonavec property within the next two weeks.

Both Specter, who in 2002 introduced the Flight 93 National Memorial Act, authorizing the Park Service to establish the memorial, and Sen. Bob Casey (D., Pa.) said they were pleased that after all the years of negotiations, park construction would finally move forward.

Specter and Casey have helped secure more than $18 million in federal funds for the 2,200-acre memorial, projected to cost $57 million.

Patrick White, vice president of the board of Families of Flight 93 and the group's point person on the real estate transactions, said he was relieved the process was over.

"It has been a long and detailed and at times seeming impossible task with the amount of issues and concerns to be addressed," said White, whose cousin Louis Nacke of New Hope was aboard Flight 93. "But with the support of folks in federal and state and local government, we were able to work in a public-private partnership to get funds and acquire land as quickly as humanly possible."

Acting Park Service director Dan Wenk said he expected real estate closings on the remaining properties to take place by mid-October and construction to begin immediately after the groundbreaking on Nov. 7.

Said Wenk: "This keeps us on track to complete the memorial by Sept. 11, 2011."