FOREST HAVEN - the grossly misnamed Siberia where the District of Columbia houses some 1,000 mentally retarded people 22 miles from the city - is supposed to close down someday. That is what a federal court ordered last year, though authorities say it may take 10 years to accomplish. These same authorities, federal as well as local, have a lot of explanations for what goes on at Forest Haven - but they do not satisfy the parents, relatives and friends of Forest Haven's residents. Complaints of physical abuse, insufficient staffing and run-down physical facilities have continued over the years; and now the facility has been notified again that it is in "serious danger" of losing its accreditation as a Medicaid facility, which could mean a loss of at least $4 million in federal money.

But unlike another facility that the city's Department of Human Resources misadministered until it was mercifully closed down - Junior Village - the responsibility for conditions at Forest Haven is not solely the District's. In 1976, the U.S. Department of Health, Education and Welfare said it would detail federal experts to assist DHR with improvements necessary to meet federal Medicaid standards. Yet DHR Director Albert Russo now charges that "HEW hasn't lifted a single finger to help us, not one iota. The copped out on us completely."

That may be, but Mr. Russo goes on to criticize the latest findings, which were issued by a survey team from his own department, since DHR performs this function in lieu of a state agency. He was quoted as saying, "I'm not having some jerks, some social workers and RNs, tell me what's wrong with Forest Haven." And he has ordered another survey.

Whatever Mr. Russo may think about his department's own employees, their chief criticisms happen to be valid. They report that the place is short-staffed, and there are more than 100 vacancies out of a total of nearly 900 authorized positions. They also cite a failure to correct physical deficiencies. Mr. Russo has noted that slow U.S. Civil Service procedures have made hiring difficult and that recent bids for construction and repair ran far too high. To his credit, the director has secured permission to hire 103 people directly and will begin interviews this week.Also, a second set of bids is scheduled for opening this week. Mr. Russo also has removed the superintendent of Forest Haven and has started a search for a replacement.

But how long will it be before these essential changes are made? Where is that help from HEW? Can't the phasing out of Forest Haven be accelerated? These are questions that should not be sidestepped or forgotten until the next crisis. Mayor Barry, Mr. Russo and other public officials should move immediately to improve conditions at Forest Haven - not over the next decade, but now.