Duane Duryea fears the government will take away his home, which lies on a one-acre lot surrounded by the Manassas National Battlefield Park. He fears the National Park Service will condemn and buy his property to make it part of the park.

Duryea is one of about 34,000 Americans who own property within a national park. Many of these people are becoming increasingly upset as the park services steps up its continuing efforts to acquire their land to make it part of the park system, according to one of the owners.

That owner, Charles Cushman, who lives in Yosemite National Park in California, is so upset by the park service's land acquistion practices that he has formed the National Park Inholders Association, which he says represents thousands of "inholders," people who own land in national parks.

Tonight, Cushman will hold a meeting at the Howard Johnson's in West Baltimore to discuss with inholders what he calls the park service's "flagrant disregard" for their property rights. Duryea said 200 people have been invited to the meeting, which follows one Cushman held last night near Williamsport, Md.

The unrest of inholders like Duryea results largely from a change in park service policy. Last September, the park service revised its land acquisition policy and decided to condemn any inholder property which the owner was improving.

William Weidenhamer, acting chief of the NPS land acquisition division, said the agency had been criticized by Congress and the General Accounting Office for letting inholders improve their property because the improvements increased the cost to NPS when it eventually bought the inholders' property.