Two members of the Prince William County Board of Supervisors, who have long opposed any expansion of the Manassas Battlefield National Park, said yesterday they might support a new proposal by Sen. John W. Warner (R-Va.) to add 700 acres to the park.

The Warner proposal contrasts to a 1,715-acre expansion supported by Rev. Herbert E. Harris II (D-Va.) and the House National Parks subcommittee.

Limiting the amount of land to be added to the park "would go a long way toward reducing the impact and cost" of a larger park on Prince William, said Supervisor A. J. Donnelly yesterday.

Donald L. White, vice chairman of the county board and another park expansion critic, said Warner's proposal is "better than anything I've seen."

In a meeting between Warner and four Prince William County supervisors, the senator yesterday suggested adding only 700 acres to the park, a much smaller area than the House National Parks Subcommittee has approved.

For four years the House parks subcommittee has passed an expansion bill but the three previous bills have died in the Senate because Virginia's senators have refused to support the proposal, citing local opposition.

"I hope this will settle the controversy," Warner told the supervisors as he outlined his proposal: "I think we have a solution here that is in the best interests of the local community and still protects the historical significance of the park," scene of two Civil War battles.

Aside from the number of acres to be added to the park, Warner's proposal differs from the bill sponsored by Harris by excluding several hundred acres alongside Interstate Rte. 66, considered as some of the most valuable real estate in Prince William County.

Warner met with Harris yesterday afternoon. Following their 20-minute session, Harris said he was "very encouraged to have Senate sponsorship of a Manassas Park expansion bill."

But Harris said he wasn't prepared to drop his own proposal, "My bill was very carefully crafted," Harris said. "There are no extraneous land or features in my bill." He said that "the entrance of the park should be protected from industrial use."

A Warner aide said the four members of the Prince William County board assured the senator they could protect the entrance through new zoning regulations limiting the height and use of any structures built near the entrance.

Warner's bill would add about two-thirds of the Brawner farm to the park, an area many historians agree is the most significant historical parcel of land not within the park. Warner said he was leaving out the other third of the farm, west of a power line, so that the county could acquire the land to build a bypass for State Rte. 234, which now runs through the park.

Also omitted from Warner's proposel, which he said he plans to introduce in the Senate next week, are about 500 acres in Fairfax County, on the north and east sides of Bull Run.

Board Chairman Kathleen K. Seefeldt, who favors expansion of the park, said she is hopeful that Warner's proposal will be "the basis for a Compromise that can get through Congress."

Supervisor A. E. Humphries called Warner's plan "the most reasonable version of an expansion bill that I've seen this far." She said "it attempts to address the needs of the county, inholders and of some historians. It's something I could support," she said, noting that she is not adamantly opposed to the Harris bill.

"It's a good starting point." Humphries added. "It won't end all controversy, but nothing would."