George Hawkes paid about $720 to a publicly funded center in Arlington last year so that his 33-year-old retarded daughter Patty could receive training in such skills as stringing beads and stuffing envelopes five days a week.

This year Virginia officials are suggesting that the Hawkes family should pay a bigger portion of Patty's tab at the center, perhaps the entire $5,160 costs.

Hawkes, a Defense Department attorney, said he can afford to pay the higher fees if he has to, but what bothers him is the state's assumption that his family -- and thousands of other middle-income families across the state rather than the government -- should pay most of the costs of their children's treatment. His daughter is one of an estimated 87,000 retarded or mentally ill adults and drug abusers who are likely to be affected by the state's decision to transfer the costs of community-based treatment programs.

"It just doesn't make any sense to single out one small group that's tried to do the best for their children and say they're responsible for their children after the age of 21," said Hawkes. "It just doesn't seem fair."

The state, he said, doesn't insist that parents of adult felons pay the costs of keeping their offspring in prison.

County and state mental health officials say the state is planning to bill families only for what they can afford to pay and say no needy individuals will be denied care. They say Virginia's "reimbursement" plan, adopted in 1980 in the state's balanced-budget tradition, is needed to combat projected budget shortfalls and the Reagan administration's efforts to cut federal support for human service programs.

"If those who have the ability to contribute do not do so, there are less services overall. So those who can't pay don't get all that they're entitled to," said Robert H. Shackelford Jr., administrative services director for the state Department of Mental Health and Mental Retardation. "It's a real balancing game. You want to ask people whether it's fair for someone who lives in a $150,000 home and drives a Mercedes not to contribute."

"In an ideal world everything would be totally free, but you just can't afford to do it that way," said state Del. Mary A. Marshall, a Democrat from Arlington who helped draft the state's reimbursement plan. "Unless there are fees charged, there won't be any money for some services."

Interest groups for the handicapped and disabled disagree, arguing that Virginia's policy is an ominous experiment that will place an undue burden on parents and discourage many needy people from seeking services.

"This kind of thing can set our social policy back a few decades," said Myrl Weinberg, assistant director of the Association for Retarded Citizens for the United States, adding that many states are considering similar action. "I would predict that this will mean more people will wind up remaining dependent, remaining in the home, and requiring additional kinds of assistance from the state," she said.

Maryland officials have toyed with the idea of a similar payment play. "I suppose someone will kill me for saying this, but I thought were rather unique in even daring to discuss it," said Stanley R. Platman, a Maryland mental health official.

Nowhere in Virginia have the protests been louder than in the Washington suburbs, one of the state's wealthiest regions, where local community services boards are just beginning to develop payment schedules. A sliding scale under consideration in Arlington specifies that a family earning $50,000 a year would be liable to pay up to $5,700 for services that had previously cost $720 or less a year, and a family with an income of $90,000 would pay up to $11,730.

In Alexandria, the proposed annual bills are even higher -- up to $8,700 for a family earning $50,000, and up to $13,700 for families earning $90,000.

"It seems to me that the system was designed to replace tax dollars with private dollars," said Stephen H. Moellering, executive director of the Arlington Adult Developmental Center, which Patty Hawkes attends. It is one of 13 agencies funded by the Arlington Community Services Board. "To my mind that's not a way of expanding programs. It's just a way of shifting the burden to the user."

Virginia's reimbursement controversy began in 1980, when state legislators approved a bill calling on the state's 37 community services boards to "maximize" the collection of fees from persons receiving community services for mental illness, mental retardation, and alcohol and substance abuse. A subsequent amendment limited fee collection to the costs of a maximum of 1,826 days of care, or about seven years of a five-day-a-week program.

The measure was an effort to set a uniform standard for fee collection among the boards, state officials say, and was designed to allow the state to collect from insurance companies for the care given to patients.

The state's residential institutions for the mentally ill and the retarded have been collecting fees from the families of their patients since the late 1940s, while the community boards had been doing it haphazardly since 1968.

"We feel that if we have a complete lock on reimbursement, the potential is there to continue to improve services," Shackelford said. "It's out there. We know it's out there."

Still, critics such as the Northern Virginia Association for Retarded Citizens argue that virtually none of the retarded adults who receive training at community centers hold any insurance that could cover the cost of that training.

For the Arlington services board, whose budget has grown steadily to $5.5 million this year, the reimbursement proposal is less a matter of economic necessity than a desire to comply with the state law.

"I think we look upon it as an unpleasant task," said Jonathan Kinney, who was among the drafters of Arlington's reimbursement proposal. "But as long as the legislature is there, there is a requirement to abide by the law."

That logic offers little comfort to people like Earl Brunson, a retired federal worker who said he fears that the fee system might force him to pull his daughter Janet, 22, out of an Arlington center for the retarded. "The money involved may not seem to be much to a two-income family, but we've been living at a lower level since she was born," said Brunson, whose wife gave up her job as a teacher in Arlington to care for their daughter.

"Sure I'll pay as long as I can afford to do so," he said, "but I won't always be able to do so."