Congress votes to protect two Civil War battlefields. But 20th-century sprawl still perils many historic sites

Two major Civil War battlefield parks - Bull Run and Antietam - have just won a battle of their own. Congress has approved two bills that will better protect them from the inroads of the 20th century. But historians and environmentalists say that much more must be done to preserve America's historic sites for future generations.

Most important, Ian Spatz says, is to change the process by which history is too often protected in the United States. Mr. Spatz, counsel to the National Trust for Historic Preservation, seeks timely identification of the threats to historic sites and ``early intervention'' - which often requires money - to protect them.

Equally necessary, he says, is a cooperative process that involves local officials, citizen groups, and state and federal governments. Just such a coalition was in action to produce the proposal to acquire more land at Antietam, where Robert E. Lee was rebuffed in the first major Confederate invasion of the North.

Far too often, Spatz says, preservation occurs only as an emergency action, as was the case at the Bull Run. He cites that example as ``not the way to make public policy ... under the threat of a bulldozer.'' Developers were in the process of constructing a large shopping center on land nearby, which Uncle Sam agreed to buy Nov. 11, when President Reagan signed an acquisition bill.

But says Spatz: ``I've never seen two places that have the same problem, the same issues.'' Thus he pleads that each site be individually evaluated.

Yet one common challenge for many is what Spatz calls ``visual intrusion,'' which stems from the onrush of urbanization as it moves toward historic places that often had been isolated.

Gettysburg is a clear example. More is known of what occurred in the climactic battle there a century and a quarter ago than is known of any other major battle of the US Civil War. Many of the more than 1 million tourists who visit it annually are deeply moved by what they see here. Many of the key areas of the battlefield are protected by federal government ownership.

At the same time ``the character of this battlefield is really influenced by the terrain around it,'' notes Bob Prosperi, a Gettysburg National Park historian. To preserve the quality of the park for future generations what is most required, he says, is ``protection of the land outside the park.''

This need not be achieved by buying the land, Mr. Prosperi says. It could be done less expensively, through easements on surrounding land which limit the uses to which it can be put. Or by passage of land-use ordinances to achieve the same effect.

A decade or more ago history buffs were up in arms over plans to construct a tall viewing tower, since built, on the edge of the Gettysburg battlefield. Their complaint: that it would intrude visually into landscape in a way that would make it more difficult for many visitors to sense the flavor of land as it was during the 19th century.

Today talk arises from time to time of tearing down the tower. But a series of practical considerations, from cost to the tower's fine view of the central battlefield, make such an action unlikely, at least in the near future.

Many historic sites are beset by problems other than visual intrusion: traffic congestion, heavy development, air pollution, and even toxic waste. Thus, no nationally imposed recommendations for park problems will be sufficiently flexible to actually solve them, Spatz says.

``This must be done on a park by park, historic site by historic site, basis,'' he says.

One of the two new laws expands the amount of parkland that the federal government can own at Antietam. Previously the limit was 600 acres.

But the size of the actual battlefield park now is 3,246 acres, with some 2,600 of those acres in private hands. No law existed that would have prevented some or all of this land from being sold and developed into apartment buildings or other structures.

The new law authorizes the federal government to acquire any or all of the privately owned 2,600 acres. This could be achieved either through purchase or donation.

Similarly, land surrounding other historic sites is owned privately by individuals who are holding it. Their hope: that the governmental department, or the historic association, that owns the site will be able to raise the money to purchase the private land and thereby expand the park.