A.D.C. City Council committee reached tentative agreement yesterday on tightened rules that would deny unemployment compensation payment to many workers who quit jobs voluntarily or are fired for gross misconduct.

The rules are part of a proposed overhaul of the city's jobless pay program that is designed to restore it to solvency and pay off a $64.4 million debt to the U.S. Treasury accumulated during the recent recession.

Under a compromise proposal accepted by members of the council's committee on employment and economic development, the total elimination of payments to job quitters and those fired for extreme wrongdoing would not be automatic. The D.C. Unemployment Compensation Board would have to decide each contested case on its merits.

Yesterday's committee decision was by consensus, with a formal vote delayed until Feb. 15. Meantime, committee aides were told to draft language to nail down the agreement.

Passage of the new measure by the full council is not certain, although the council usually accepts recommendations from its committees.

Because the proposed rules allow the Unemployment Compensation Board to make judgments, there was no estimate of how many of the 60,000 annual jobless pay beneficiaries in the city might be affected by the new rules.

The Metropolitan Washington Board of Trade, the city's largest employer group and a supporter of complete restrictions on the two groups of beneficiaries, estimated that such rules would remove 8,000 persons from the rolls and save $11 million a year.

Organized labor, represented by the Greater Washington Central Labor Council, protested the restrictions, saying they could be bent by employers so as to deprive jobless workers of benefits they need to survive.

"Only a few, a small percentage, are abusing the system . . . the vast majority are not out here to rip off the system," Robert E. Petersen, president of the labor council, told the committee.

Labor spokesmen have contended, for example, that many workers quit jobs under threat of being fired for flimsy reasons and that such workers, under the employers' proposal, would to barred from collecting benefits. Others quit because of bad working conditions or unsuitable hours, the spokesman asserted.

Under existing rules, workers who quit voluntarily or are guilty of misconduct can be kept from receiving benefits for 5 to 10 weeks of the maximum 34-week benefit period but cannot be barred outright.

One employer who testified before the Council committee, headed by Wilhelmina Rolark (D-eight), cited the case of a store clerk who stole merchandise yet was able to collect $1,396 in jobless benefits.

What galls employers, they said, is that they are taxed to create the fund from which benefits are paid. Employes make no contribution.

The heart of the new legislation is a tax table under which employers would pay a basic D.C. unemployment tax ranging from 0.1 to 4 percent of their covered payrolls, depending on the solvency of the compensation fund and the extent to whcih each employer's former workers collect from the fund.

The present tax is a flat 2.7 percent on all covered payrolls in the city.

In addition, Mayor Walter E. Washington proposed levying a 1 percent surtax to pay back during the next four years the $64.4 million borrowed from the Treasury. The compromise bill would shave the surtax to 0.9 percent. While the percentage drop is small, the reduced surtax would cut tax payments in the fund next year from $17 million to $15.3 million, fund officials said.