George Washington University is attempting to get District approval for a new medical building on its campus -- despite opposition from two neighborhood groups, school officials say.

The university, which wants to start construction this summer, needs the new structure to house the university's health maintenance organization by the end of 1986. The lease for the building where the HMO is now located runs out at that time.

Robert E. Dickman, assistant treasurer for the university, said the federal government, which owns the building at 25th and N streets NW, wants it back, and there is no possibility of renewing the lease.

Meanwhile, neighborhood opposition to the new HMO building has pushed back hearing dates all spring as residents have asked D.C. officials to reconsider the university's application.

"We're not trying to delay it, we're trying to kill it," said James Draude, of the President Condominium Association. "We don't want them to start this summer or next."

Neighbors in the condominium, which is next door to the proposed building site at 22nd and I streets NW, say the new HMO building would be too high and would block the sunlight of the residents who live on the west side of the building. The university currently maintains a small parking lot on the site.

Dickman said the eight-story building is needed to house the HMO as well as faculty offices and would be connected to the existing Burns Medical Building via a bridge or tunnel.

The university must get permission from the District Board of Zoning Adjustment whenever it wants to build on campus, Dickman said. He said the proposed HMO building fits in with the university's master plan that has already been approved by the District but still must go before the board.

"Our case is very consistent with the already-approved zoning designs," he said.

However, neighbors already have succeeded in delaying the board hearing from February to next month, arguing that the university is attempting to add onto a non-conforming structure because of the link to the existing Burns building.

The Foggy Bottom Advisory Neighborhood Commission also has come out against the proposed building. Representatives of the ANC and the President Condominium spoke against the university's plans at a City Council Finance and Revenue Committee meeting earlier this month during hearings on the university's application for $73 million in revenue bonds.

The university would use $42 million worth of the bonds to finance the new HMO building and the remainder for several communications, video and computer projects throughout campus, Dickman said.

A spokesman for the finance committee said the university's request had not yet been scheduled for a markup, the first step toward approval.

"Obviously, we are under a tight schedule," said Dickman. "We are hoping that the bonds and the zoning approval will all come together in time for us to start construction at least by early fall."

"We don't care how long it takes," countered Draude. "We are opposed to the density. We'll fight it."