At least six nonprofits have applied to use the former Army Reserve Center on Carroll Street to assist the homeless. But if none of their applications is approved by the federal government, the property could go to the city.

The building, which has been vacant since 2012, was declared surplus in December. Under law, the U.S. General Services Administration must look first to see if it can be used for homeless services. If there is no suitable application in that category, the property can be conveyed to a local government through the Federal Lands to Parks program. If there are no takers in that category, the surplus property goes on the open market.

Turning the armory into a park is still a hypothetical solution, deputy city manager Keith Chadwell told Durham City Council members Thursday. The Parks and Recreation Department is asking the council to approve a resolution supporting its plans so that it can move forward with the application process.

The armory is located on about 5.5 acres of land in a residential area. At a neighborhood meeting in February, some residents said they’d like to see a park rather than a homeless shelter there. Lyon Park surrounds the property on three sides.

There are some environmental concerns about the property.

According to the GSA, four structures totaling 24,724 square feet comprise the site, including “a vehicle maintenance shop, a small hazardous materials storage unit and storage warehouse.” Asbestos and lead-based paint are present, the agency said. The state has classified the facility as an inactive hazardous site in need of no further remedial action. A city memo says the site had housed an incinerator, “which raises the potential of toxic soils on the site.”

“The proposal being developed by [Durham Parks and Recreation] would not disturb the soil layers and would safely cap the subgrade with additional courts and asphalt parking,” the city memo said.

If the city ends up with the property, turning the space into a recreational facility would be an approximately $4.2 million project, including outdoor athletic courts, trail extensions, parking, a courtyard, and renovations to the existing building to upgrade the kitchen, add interior courts, and bring the building up to code.

CASA, which provides permanent supportive housing, has expressed an interest in the building. Anthony Scott, CEO of the Durham Housing Authority, said his agency is not applying to acquire the building but “has reached out to other interested parties and advise that we are willing to partner with them.”

Council member Jillian Johnson asked whether the city could put the building to use serving the homeless.

“The potential uses are restricted as provided by the federal government— a park use or a recreational use,” Chadwell said.