From the Stone Bridge over Bull Run, visitors to the Manassas National Battlefield Park can see the spot where Union soldiers launched a diversionary attack that began the first battle of the Civil War. In a nearby woods, trees still bear shrapnel from the second battle at Manassas a year later.

Those historic confrontations occurred more than 115 years ago, but today a new battle has been joined, not on the rolling fields of Prince William County, but in the committee rooms of the United States Congress.

The issue is whether the 3,000-acre park should be expanded by another 1,400 acres, and unlike the classic Union-vs-Confederacy alignment of 1861 and 1862, the present-day battle lines are not so clearly drawn.

The Prince William Board of Supervisors opposes the expansion as too broad; preservationists favor it, but say it too restrictive, and area residents are divided.

The bill to expand the park, sponsored by Rep. Herbert E. Harris III (D-Va.), whose eight congressional district includes the park, has marched through the House for the last two years virtually without opposition, only to be ambushed in the Senate by opponents.

Harris proposal would add 1,400 acres around the periphery of the park, at a cost of $8.5 million. The additional land would include 55 acres surrounding the Stone Bridge over Bull Run at the eastern edge of the park, adjoining Fairfax County and the clump of shrapnel-pocket trees at the western edge of the park that mark the site of the village of Groveton, which was destroyed in the second battle.

Opponents of expansion have succeeded in getting Virginia's two U.S. senators, Harry F. Byrd Jr. (I) and William L. Scott (R) to ask Sen. James Abourezk (D-S.D.), chairman of the Senate Subcommittee on Parks and Recreation, to delay action on the bill to see if "interested groups can attempt to work a satisfactory solution."

A Senate subcommittee staff member said the requested delay "almost guarantees the Senate won't act" on the proposal unless the state's senators remove their objections.

Harris is optimistic, however, noting that neither senator said he personally opposed the bill.

During the Senate subcommittee hearing July 28 on the Harris bill, Donald White, vice chairman of the Prince William County Board of Supervisors, expressed exasperation in attempting to balance the relative importance of historical sites against present-day needs of his fast-growing county.

"Every place in Prince William County (is historic), they all rode their horses over the land, and nobody is denying it," White said in response to a statement from the National Paak Service in support of the expansion. "But in cannot all go that way. At some point it has to stop. We recognize the park is here, and we will do what we can to protect it."

But the supervisors also have "a responsibility to try to take some of the pressure off the people paying the bills" by seeking to expand, rather than shrink, the tax base of the county, White said.

While the Board "is not happy with any further takeover of county land by either federal or state agencies," White said it could support the Harris bill if certain conditions were met.

He asked the Senate to give the supervisors assurance that no federal action would prevent the county from constructing a bypass of State Rt. 234, which now runs through the center of the park, and that it would not yield to demands by preservationists to acquire still more land for the park.

At the same hearing, Memory Porter, speaking in behalf of the 100-member Prince William League for the protection of Natural Resources, urged the Senate to allow the park service to purchase another 513 acres of land adjoining the park owned by the Marriott Corp.

She said the tract not only has historical significance in its own right, but more importantly, can be seen from existing boundaries of the park, and therefore should not be permitted to be developed for industrial purposes.

White countered that the supervisors are "adamantly opposed" to federal acquisition of the Marriott property "in any way, shape or form." The tract and the proposed bypass of Rt. 234, White said, are the "key" to commercial development of the county, whose only major industrial asset, an IBM plant, recently was annexed by the city of Manassas.

The supervisors rezoned the Marriott tract from agricultural use to commercial and industrial use on April 4, 1973, in hopes it would become the location of a Marriott "Great America" amusement park similar to those in Gurnee, Ill. and Santa Clara, Calif.

The rezoning was attacked by Porter's league and last April, after a four-year court fight, the rezoning was voided on grounds that legally required advertisements announcing that a change in land use was being contemplated were improper.

If the land isn't used for a theme park, the supervisors are committed to its development for industrial use. "We can't afford to lose this resource," White told the Senate subcommittee.

In her testimony, Porter said the need for the bypass was based on traffic projections arising from development of a theme park, and with that plan now unlikely, the bypass isn't justified.

The park service also wants to purchase scenic easements on a 20-home development within the park known as the Battlefield Community. Under that plan, property owners are compensated in return for permitting the government to control any exterior changes in their property.

Harris had agreed to exempt the subdivision from his bill, but the park service told the Senate subcommittee it wants the easement "to protect the wooded character of the subdivision and prevent more intensive use which would be adverse to the park."

Porter's league disagrees with the need for easements in the residential neighborhood.

"The only thing that will ever drive these people from their expensive, single family homes on wooded lots on quiet private streets . . . is development of the Marriott property," she testified.

Proponents of the expansion have made several consessions in hopes of getting approval of the bill, including excluding the Manassas campus of Northern Virginia Community College and the Sudley United Methodist Church from the expansion.

But opposition remains. Mary H. Ferguson, recording secretary of the Sudley Church, said some church members "object to the procedure," and fear that their property could be condemned and that Sudley Road (Rt. 234) could be closed, forcing parishioners to drive much farther to get to Sunday services.

Harris is bewildered by opposition from church members. He said closing the road "is just not an issue," and added that there is no provision for the governement to condemn property to carry out the expansion.

All land to be acquired will be bought through mutual agreement, Harris said, with money provided by the Department of Interior's Land and Water Conservation Fund.

Last year, Harris' bill was blocked single-handedly by Sen. Scott, who, before he left on a trip to the Philippines, authorized a proxy vote against placing the matter on the Senate's "unanimous consent" calendar.

This year, Harris got five other Virginia congressman to join him as sponsors, but again, the bill was blocked in the Senate, with both Scott and Byrd calling for further study.

"We've answered every question that could possibly be posed," Harris said. Byrd is "the key" to the bill's passage, Harris said, adding that "we know he's sensitive to our Confederate heritage, and he's often on the side of conservationists. It will eventually be passed."