The Social Security Administration's plan to cut 17,000 full-time workers by 1990 and possibly shut some local offices is under renewed attack on Capitol Hill.

At a House hearing last week, former SSA commissioner William J. Driver charged that the proposal was not based on any feasibility study but was forced on the agency by the Office of Management and Budget, acting on a recommendation by the President's Private Sector Survey on Cost Control.

The so-called Grace Commission recommended in 1983 that the agency's work force be trimmed by 17,791 employes and that the number of district and branch offices be reduced from 1,350 to about 500.

Driver appeared before the House Ways and Means subcommittee on Social Security on behalf of the Save Our Security Coalition, an organization of 104 groups claiming 40 million members. "The Grace Commission," he said, "never assessed the impact of this recommendation on the public. The office closings were viewed simply in terms of monetary savings."

Similar sentiments were expressed by the American Association of Retired Persons and the National Committee to Preserve Social Security and Medicare.

Asked to comment, OMB spokesman Edwin L. Dale Jr. said, "Our proposal is not just plucked from Grace. It is founded on the assumption of a really significant" improvement in computer operations and systems management.

Rep. James R. Jones (D-Okla.), the subcommittee's new chairman, said, "What has concerned me is that this was an idea cooked up in the OMB by . . . the Great Slasher," a title that Rep. Silvio O. Conte (R-Mass.) recently coined for OMB director David A. Stockman.

Joseph L. Delfico of the General Accounting Office told the panel, "Whether SSA can achieve a 21 percent cut in staff without any adverse impact on service to the public is not known . . . . At present there is little evidence to serve as a basis for the projected staff reductions expected to be achieved in the outlying years . . . . "

Acting SSA Commissioner Martha A. McSteen, who has been trooping all over Capitol Hill for weeks trying to reassure lawmakers about the impact of office-closings, testified that the staff cuts can be achieved without hurting services through more use of computers and better systems design. She added that there is no preconceived total and no list of targets.

Under questioning by Jones, McSteen acknowledged that the idea for a large, long-term personnel cut came initially from the OMB, not SSA. The OMB wanted to cut 19,000 employes, but SSA succeeded in reducing that by 2,000. McSteen also emphasized that only the first 3,600 jobs would be cut by President Reagan's fiscal 1986 budget. "Substantial further reductions in personnel will be dependent on how successful we are at achieving the transition to state-of-the-art automation and in other productivity and management operations."

Gayla Reiter, president of a union representing 70,000 SSA employes on the West Coast, said that in some offices there, sacks of mail go unprocessed, "filing cabinets full of unworked overpayments and waiver requests, many of them over a year old," await action and clients sometimes have to wait three or four hours for service because there isn't enough staff. She predicted that "the hue and cry will be deafening as the administration moves to implement its planned closures." FIGHTING CHILD ABUSE . . .

The Health and Human Services Department has proposed requiring local Head Start agencies to obtain declarations from potential employes listing whether they have any prior or pending charges relating to child abuse, child sexual abuse and child neglect, plus all felony convictions and other criminal charges. The rule would require that all applicants be interviewed, their references checked and their records undergo a state and national criminal check. In addition, the agencies must advise every employe and volunteer that sexual activity with children is illegal and must draw up a plan to investigate and report on suspected incidents. MINI-INDUSTRY . . .

The new Medicare prospective payment system, under which hospital payments are fixed in advance for several hundred different illnesses or procedures, is such a big innovation and involves so many billions of dollars that a mini-industry is growing up around it.

Already a suburban Maryland company is publishing a newsletter devoted solely to the subject, and a Los Angeles insurance broker has begun offering insurance to protect hospitals against losses. The hospitals are worried because if their costs run higher than the fixed payment, or if a Medicare patient is forced to remain for an excessive number of days, they can lose money.

The newsletter, Prospective Payment Guide, costs $249 a year and has been sold primarily to hospital administrators. The insurance is handled by Gerald J. Sullivan & Associates, which sells a lot of medical malpractice insurance, and is underwritten jointly by Lloyds of London, the American International Group (N.Y.), CNA Insurance of Chicago and Hartford Insurance of Hartford, according to Wes Justyn of Sullivan. He said he has quoted hospitals premiums ranging from $30,000 to $500,000.