Tylee Smith has been trying for nearly two years to open a shelter in Fairfax County for mentally disturbed persons, but his private, nonprofit corporation, Managed Home Associates Inc., has had problems with start-up costs.

This week, social worker Smith said the project may never get underway if a proposed county ordinance regulating group homes is adopted.

The ordinance would establish a potentially lengthy - and, Smith says, costly - review process for licensing group homes.

The proposal would establish a Group Residential Facilities Commission to issue licenses for such homes and provide for appeal and review procedures if a license is denied. The process could take a long as five months.

Group homes are community facilities that typically house persons who are unable to cope independently, such as retarded persons, disturbed youths or alcoholics.

Proponents of group homes and members of neighborhood associations that oppose the location of such facilities in their communities testified before the Board of Supervisors this week about the proposed ordinance.

Citizens in favor of the homes objected to the likelihood that the lengthy licensing process would make it almost impossible for operators to buy or lease houses for use as group homes. They said owners would not want to remove property from the market for several months.

Those opposed to the homes charged that the wording of the ordinance is too vague and that there is no provision for revoking group home licenses if conditions in the homes change.

Supervisors postponed a decision on the proposal and appointed a citizens' committee to study its provisions. The committee is to report the results of its study in three weeks.

The measure now under consideration by the supervisors grew out of a county zoning board decision last summer that a group home for teen-agers, Enviroments for Human Services of Ravenwood Park, had to apply for a special use permit to remain open in a residential neighborhood zoned for homes for family use.