A D.C. government proposal to open a homeless shelter in Ward 3 for the first time has ignited strong opposition from neighborhood residents and the ward's council member.

Plans for the overnight accommodation for 50 single men were officially announced yesterday in a letter from the Department of Human Services to the Advisory Neighborhood Commission for American University Park.

But word of the proposed site in a former police station at 42nd and Albemarle streets NW, one block off Wisconsin Avenue, had informally reached neighbors and D.C. Council member Jim Nathanson (D-Ward 3) well before the official announcement, drawing immediate protests.

Nathanson and nearby residents said a facility for homeless people was not appropriate for a residential block that has two elementary schools.

"Many of our homeless sadly do have mental problems and some have assaultive personalities," said Nathanson. "Experience has shown that the people who are homeless have different lifestyles and have a negative impact on the homes and people around them."

Mayor Sharon Pratt Dixon said through a spokesman yesterday that if the shelter is opened, she will order extra police protection for the area.

Similar concerns were raised by Ward 3 residents in November when the city tried to place 100 homeless people in six trailers on private land in the 2800 block of Wisconsin Avenue.

The city backed off when it realized the land would have to be rezoned.

The city operates shelters throughout the city because Initiative 17, passed in 1984, requires the District to provide shelter upon demand. A subsequent court order required that all sectors of the city have shelters and that extra beds be added whenever the existing shelters reach 95 percent of capacity.

The District continues to operate under those rules even though the law was overturned by voters in November.

That result does not become official, however, until Congress approves the referendum.

Ann Petersen, co-president of the Parent Teachers Association of Janney Elementary School, which is across the street from the site of the proposed shelter, said her group is opposed to the shelter because it will put homeless men in close proximity with young children.

Ward 3 lies west of Rock Creek Park and north of Georgetown.

Nathanson, who said he had learned of the District's plans from a constituent, said he was unhappy that the Department of Human Services had not given the council 60 days' notice of any intended shelter placement, as required by law.

However, agency spokeswoman Rae Parr-Moore said the city, in addition to sending the letter yesterday, will place a notice in the District Register next week, thereby meeting its legal requirements.