Sears, Roebuck & Co., which filed a massive legal challenge Wednesday to government-enforced affirmative action programs, is facing one of the biggest job bias complaints ever.

The potential penalties against Sears could be greater than the Equal Employment Opportunity Commission's $31 million settlement with the steel industry or its $32 million agreement with General Electric Corp.

The government's claims against Sears could approach the scale of EEOC's settlement with American Telephone & Telegraph, which agreed to give $12 million in back pay and $40 million in raises the first year and is expected to pay eventually $100 million in compensation to women and minority workers.

The potential scope of the Sears-EEOC case was estimated yesterday by officials of Sears and the Chicago chapter of the National Organization for Women, a leading critic of Sears employment practices.

The EEOC, with which Sears said it is holding conciliation talks, is prohibited by law from commenting on pending complaints.

"The government thinks they've got a case like steel or AT&T," Ray Graham, Sears equal opportunity director, said at a breakfast meeting between Sears executives and reporters.

"We totally disagree with their finding in every respect," Graham added, defending the company's affirmative action program and challenging EEOC "to show us any company in the U.S. that has better results."

Claims for compensation of women and minority group members who allegedly suffered job bias at Sears "will be closer to the telephone company than to steel," said Ann Ladky, former president of the Chicago NOW chapter. "The back pay liability alnoe could run into millions."

The EEOC has the power to sue private employers for back pay, future raises and a broad range of other remedies to make up for alleged discrimination. EEOC's biggest cases -- against AT&T, GE and the steel industry -- have been settled by negotiation.

But Graham said yesterday "the likelihood is slim indeed that the commission would agree with us on what is, in fact, equitable."

An injunction preventing the Eeoc/ or other government agencies from taking action against Sears for job bias is the major legal remedy asked in a lawsuit Sears filed Wednesday against 10 federal government a gencies.

Filled in U.S. District Court for the District of Columbia, the case was assigned by a random draw to Judge June Green, the only woman on the local district court bench.

Private employers cannot be held responsible for having too few women or minority workers when government actions for 40 years have given white men a head start in the race for jobs, Sears' lawsuit contends.

The petition also asserts that federal agencies "failed to enforce the civil rights and equal opportunity laws within their jurisdiction, thereby depriving Sears of a sexually and racially integrated workforce."

Although the case could result in a far-reaching challenge to federal efforts to force private employers to increase job opportunities for women and minority group members, Sears executives stressed yesterday the company is still committed to affirmative action.

In a letter to Sears Xecutives, Chairman Edward R. Telling said, "There are those who might be tempted to view our action as a delaying tactic or a signal that we intend to moderate our affirmative action determination. Nothing could be further from the truth."

Sears President A. Dean Swift, meeting with reporters in Washington, said Sears sued "out of some frustration" with the difficulty of complying with "conflicting and contradictory" government hiring mandates.

One goverment program insists the company hire Vietnam veterans, another that it hire minorities and women, a third the handicapped and now the Labor Department has ordered hiring preference for former alcoholics and drug abusers, complained Charles Bacon, vice president for personnel.

With Sears executives telling their side of the EEOC dispute in Washington and in Chicago, Swift acknowledged the company was taking its case to the public but said the suit was not intended merely as a public relations move.

"We intended to do just exactly what it says here; if that has public relations impact, that's great," he said. "This issue should be foremost in the minds of every corporation in the country."

In Chicago, NOW member Ladky complained that Sears could have settled its differences with the EEOC rather than sue. "I don't think the EEOC has ever been up against a more litigation-prone company," she added, saying Sears had sued NOW and other groups to keep s ecret information about its personnel practices.

Ladky, who works for Women Employed, a Chicago project aimed at improving job opportunities for females, was president of the NOW chapter in Sears' hometown when the women's group launched a major attack on Sears alleging bias against women workers.

She and NOW member's went into Sears' stores and surveyed workers in Sears Tower -- the tallest building in the world -- to provide data that became the basis for the EEOC investigation.

Although more than half of Sears' employes are women, a disproportionate number of them hold part-time jobs that pay less and provide fewer fringe benefits and fewer opportunities for advancement than full-time positions, Ladky said. Sears said 67 percent of its part-time workers are women, but claims that is because government policies discourage women from working full time.

Ladky said NOW found few women working in Sears best-paying jobs -- such as appliance sales where commissions are earned -- and found only a handful of women store managers in Sears' hundreds of stores.

The EEOC case against Sears reportedly is based on the large number of complaints filed against the company.

Acknowledging there have been 1,500 job bias charges against the company, Graham called that "an infinitesimal number when compared with the tremendous number of personnel decisions over the past 10 years."

With 400,000 workers on its payrolls, Sears has made 1 million decisions to hire and promote in the past decade, he said. The company policy now is to hire one woman or minority worker for every white male in most jobs and one women or minority worker out of eyery five in "non-traditional jobs" -- such as auto mechanics, Eeoc/ has refused to accept that plan, Graham said.