A plan to build an office building, laboratory and seven-story parking garage on a swath of undeveloped land at Walter Reed Army Medical Center has drawn strong opposition from Shepherd Park residents.

Officials with the medical center have told community groups that they want to build the facility on eight acres at 16th Street and Alaska Avenue NW. Preliminary plans call for a 550-car parking garage, atrium, 282,000-square-foot laboratory and 272,000-square-foot office building.

Residents have long admired that area of the military hospital -- a green, park-like setting across from Rock Creek Park that serves as a counterpoint to the bustle of nearby Georgia Avenue NW. The project has raised a host of concerns for numerous residents, including the Shepherd Park Citizens Association, and for city officials such as D.C. Council member Adrian M. Fenty (D-Ward 4), whose district includes Shepherd Park.

Some residents say the development would cause traffic and parking headaches, as up to 1,200 employees would work in a new facility planned to have parking for only 550 cars.

Some question the project's lease arrangement. The "enhanced use" lease allows a private developer to build and maintain the property, a move military officials said is beneficial because it uses private capital instead of government funds. Residents worry that it would create a gated commercial development in a residential area.

Others are concerned about the kind of research that would go on in the lab and the fate of a number of historic structures. Still others complain about the loss of old trees and the transformation of a quiet, undeveloped corner into what they said would resemble a suburban office park.

"It would seriously encroach on the green space," said Ralph Blessing, 59, who lives about two blocks from the hospital and is a former president of the citizens association. "It doesn't match what we in the neighborhood have been accustomed to."

Walter Reed officials said the purpose and size of the site are now being reexamined. "We have heard the community loud and clear," said Col. Jeffrey Davies, the garrison commander at Walter Reed who oversees infrastructure and buildings.

The nation's largest military hospital, at 6900 Georgia Avenue NW, is a sprawling campus on 113 acres. Davies said the project is necessary because of a need for additional lab space and a desire to bring activities done off hospital grounds back onto the campus. But he said officials within the Department of Defense are looking into the "mission requirements" of the site, and he said that as a result there are "no set plans at this particular point. We're going to take a fresh look."

He said that once the mission of the new facility is defined, hospital officials will have a better idea of the size of the project. Until then, he said, the details concerning the green space, parking and other issues remain undetermined.

But Davies said the hospital wants to "save as many trees as we can" and to maximize the use of mass transit by employees to reduce the number of cars. He also said the lab would do basic science and research, and that there were no plans for the lab to have Biosafety Level 4 capabilities. Biosafety Level 4 labs, such as the Army's lab at Fort Detrick, Md., are equipped to study the most hazardous pathogens.

"We took the community's concerns to heart and wanted to make sure that as we go down the road on this, that we are able to have a win-win for everyone," Davies said.

A community task force has met with Walter Reed officials about the plans, as have Fenty and Del. Eleanor Holmes Norton (D-D.C.). Norton wrote a letter to the hospital last month requesting a full environmental impact statement.

Fenty said the location and size of the proposed building are all wrong. "It's completely counter to the character of that area," he said. "It's counter to what you find going up 16th Street and eliminates very pleasant green space. . . . This is the biggest piece of green space on 16th Street besides Rock Creek Park itself."

Fenty and several residents want the hospital to find another location for the facility, perhaps closer to the center of the campus in one of the medical center's roughly 74 existing buildings. They said they were not notified before the hospital recently decided to cut down a number of trees along 16th Street for a separate project, and are hoping for better communication on the new proposal.

"What we'd like is to be able to have some input and hopefully modify it so that it's something we can all live with," said Rosemary Reed, who's lived in Shepherd Park more than 30 years. Reed, president of the civic organization Neighbors Inc., said residents "would just like to keep the greenery. . . . I think it's a visual impact."

Residents have fought unwanted development in the past, forming a legal defense fund in the late 1980s to block an eight-acre commercial and residential project near Georgia and Eastern avenues NW. This time, residents say they are just as determined, making plans to get documents under the Freedom of Information Act.

Four Ward 4 advisory neighborhood commissioners sent a letter to D.C. Mayor Anthony A. Williams (D), noting that the development would "adversely affect the quality of life" in the community.

Ralph Blessing and Rosemary Reed oppose plans for new labs and parking deck. "It would seriously encroach on the green space," Blessing says.