A detailed plan to move nearly 900 mentally retarded men, women and children from the Forest Haven institution back into the metropolitan community has been submitted to U.S. District Court Judge John H. Pratt.

The plan, developed by the Department of Human Resources, would shut down Forest Haven - the city's only public institution for the mentally retarded - by October 1987. DHR officials said no estimates of the cost of the program are available at this time.

The Forest Haven implementation plan is the city's response to a 1977 court order by Judge Pratt, known as the Pratt Decree. The decree required DHR to provide "habilitative" care to Forest Haven residents and devise a plan that would gradually phase out the trouble-plagued facility by returning the residents to the community.

According to the proposal, which must be approved by the court, the shut-down would result from the development of personalized "exit plans" for each Forest Haven resident. These exit plans, which will be used to move residents into the community, would identify the capabilities of each resident and help the resident and relatives (or surrogate parents) plan long-and short-range goals, housing needs, job-training programs, recreational outlets and educational and homemaking skills programs to help the person live in the community as independently as possible.

The exit plans would be developed after thorough physical, psychological and social evaluations of each Forest Haven resident. Each evaluation would be updated annually, whether the person was living atForest Haven or in the community, the plan states.

Community living arrangements would include foster homes, nursing homes and supervised and independent apartment arrangements. Group homes would house no more than eight people, the plan states.

All homes, other than independent apartments, would be run by private operators who would be paid under contracts with DHR.

"There shall be no Forest Haven-operated group homes, or apartments established from the time this plan is accepted by the court," the plan states.

DHR also submitted an interim operation plan for preventive and punitive actions DHR can take to address complaints of abuse and neglect of residents by Forest Haven personnel. DHR still must submit a proposal for reassigning Forest Haven workers to other duties during the 8 1/2-year phase-out of the institution.

"The city has taken the position that, at minimum, this is what's going to be. We're not going to take anything out," Charles Indlander told a group of 30 skeptical people, most of them relatives of Forest Haven residents, at a recent community meeting on the proposals.

Inlander was hired by DHR, as part of Judge Pratt's order, to help the department formulate a plan for closing Forest Haven. Under the court order, Inlander is required to report the city's progress to the court every 90 days.

The relatives, who apprehensively questioned the plan, sought guarantees that their relatives would not live in contract homes such as one in Mount Pleasant where a fire recently resulted in the death of 10 mental outpatients.

Inlander assured them that no Forest Haven residents would be placed in homes not licensed under the Community Residential Facilities Licensure Act of 1977. The act sets uniform standards for maintenance and operation of group homes. The Mount Pleasant home was not licensed under this act, although it was licensed as a boarding home.

The relatives also asked for Inlander's assurance that good staff workers and services for their relatives would be more readily available in Washington than at Forest Haven.

And they asked about DHR. Would DHR be any more responsive to their relatives' needs in the community?

Regarding the first concern, Inlander said he believed it would be easier to hire people for community programs than for institutional ones.

As for DHR's responsiveness, "I'll be honest with you," he said. "I have as great a question as you do whether the government is going to do it right."

As they left the meeting, bewildered relatives shook their heads in dismay.

One man, Robert Tilghman, said his 34-year-old brother has been at Forest Haven 26 years. Tilghman said his brother can't speak, but through the evaluation process psychologists are finding his intelligence is greater than they had expected.

There's hope in the plan, Tilghman said. Yet, he said, he doesn't feel the complexities of it have been fully comprehended.

"I'm not at all optimistic about this contractural(living) arrangement," he said, mentioning one of his chief concerns.

Another relative, Debbie Walker, said, "It sounds positive. I'm fully behind everything. This has been the most positive talk I've heard in a long time."

Walker said her brother has been at Forest Haven 10 years. When he entered, he was a robust athlete, she said. "He's riding in a wheelchair now," she said bitterly, and the family can't find out why. "That's the mystery of Forest Haven."

The court decree ordering the eventual closing of Forest Haven resulted from a 1974 class-action suit filed by the relatives of several Forest Haven residents. The parents of Joy Evans, a young woman who died at Forest Haven, were the main plaintiffs. The Evanses contended that their daughter's death resulted from neglectful and abusive conditions at the institution.

A total of 840 people now live at Forest Haven. The Pratt Decree requires that a minimum of 200 residents be relocated by October 1980. So far, 58 residents have been returned to the community.

Despite its idyllic name, and the peaceful, wooded surroundings of the Children's Center in Laurel, Md., the 54-year-old institution has remained the subject of continuing controversy about physical abuse and neglect of residents.

Recently, several staff members were accused by their colleagues of beating residents with rubber hoses, DHR officials have said. Two of the staff members have since been arraigned in federal court in Baltimore on assault charges.