Gaithersburg is girding for a fight with Maryland health officials over the state's recent approval of a group home in the city for eight mentally disabled persons, a plan that conflicts with a local ordinance prohibiting more than five unrelated persons living together in a residential area.

"We have a disagreement on the number [of residents]," City Manager Sanford W. Daily said. "I don't necessarily think there is a disagreement on whether the group home can go there." The city is willing to allow a house with five occupants, officials told the state.

However, some neighbors of the house at 116 E. Deer Park Rd. have told city officials that turning it into a group home would change the character of their neighborhood. Some contend that a lack of sidewalks there could pose a safety threat for the home's residents.

The state Department of Health and Mental Hygiene recently granted a license to Family Services of Montgomery County Inc., a nonprofit agency, to operate its first facility.

A spokesman for Family Services said that the agency would not be able to cover the home's operating expenses if it had only five persons living there.

City officials recently sent a letter to state health officials opposing the plan and are waiting for a reply.