For 26-year-old Quinta Castle, the dilapidated Oxon Hill plantation known as Mt. Salubria, complete with log cabin kitchen and refurbished slave shack, holds more than a century of hand-me-down memories.

Castle represents the fifth generation of the Dr. John H. Bayne family to live in the massive home and own the once-thriving tomato plantation. When Bayne built the house in 1827, he named it Salubria, a Greek word meaning "in good health."

Today, the white clapboard house is choked with weeds and ravaged by the elements, neglect and a fire that gutted it three years ago. Castle and her older brother Kevin, who live on the 50-acre estate, cannot afford the $500,000 restoration or upkeep on the house and have sold the property to developer Ronald Cohen. Preservationists fear that the landmark house may well go the way of other historic buildings that have been overrun by Prince George's County's development wave.

But a bill scheduled for a public hearing before the County Council on Tuesday could save Salubria and 20 other historic county properties like it by giving developers and others in the private sector incentives to make them profitable again. Those 21 buildings have been targeted by county preservationists because they are considered too large or too dilapidated to serve as private residences and could be put to best use as commercial ventures.

Buildings like Salubria are today "just too big and expensive to maintain as houses," said Gail Rothrock, head of the county historic preservation commission. A local jurisdiction such as Prince George's does not have the resources to support all the buildings that need to be restored, she said. Once they are acquired for such a purpose, they are taken off the tax rolls.

The bill would allow, through "special exception zoning," alternate uses for large historic properties in residential, commercial and industrial zones. For example, Salubria, which is in a residential zone, could be transformed into a country inn, a condominium complex, an office building or a museum, based on recommendations made by the county historic preservation commission. The bill is designed to ease developers' costs in securing such uses since zoning changes now can cost $25,000 to $30,000.

In reviewing special exceptions, the commission would ensure that restoration would not change the exterior or have an adverse impact on the area surrounding the site. The commission would also determine the type of building use that would be compatible with its structure.

"You couldn't operate heavy machinery in certain houses that are just not equipped for all that vibration," Rothrock said. And the bill would allow greater public access to some of the county's historical sites, she said.

According to John Lalley, a lawyer for developer Cohen, the bill would be an incentive for preserving Salubria. Although Cohen plans to build a 37-acre industrial park north of the estate, Lalley said, the bill will solidify his preliminary plans to transform Salubria into a country inn.

The inn "is not a cost-effective thing," Lalley said. "It might cost us $350,000 extra to renovate the existing building. If you're a developer, it is not smart to keep an old house. You knock it over. But the whole idea of having Salubria preserved is to have a historic landmark that people can go and use. A living type of facility, not a mausoleum.

"In renovation, the more sensible thing is to use aluminum or vinyl, but we will use wooden planking and whitewash," Lalley said.

Since the establishment of the county Historic Preservation Commission in 1981, an arm of the Maryland-National Capital Park and Planning Commission, "adaptive reuse" has been used successfully in Prince George's, said John Walton, coordinator of the history division of Maryland-National Capital Park and Planning Commission.

"What's kept it going is increased awareness of the public and elected public officials," said Walton, who recently succeeded in getting bills passed in the state and county for the renovation of three historic buildings owned by the park and planning agency: The Buck House in Upper Marlboro, Riversdale in Riverdale and Marietta in Glendale. The three buildings, two of which are on the National Register of Historic Places, will serve as office space for the park and planning commission, Walton said.