Even as Congress continues to fight over this year's budget cuts, the Office of Management and Budget is preparing a new round of retrenchment for fiscal 1983 that would do away with several more manpower programs, cut the Environmental Protection Agency by a third and chop education programs in half.

The administration has repeatedly warned it intends to propose further budget cuts next year in its campaigns to shrink the government and the deficit.

Leaked budget documents and remarks by agency officials yesterday revealed that among the new cuts now under consideration for fiscal 1983 are these:

The Labor Department, in a confidential memorandum prepared for the OMB, has suggested cutting obligations for job-training and related programs to $3.4 billion in fiscal 1983. The same block of programs totaled $8 billion in fiscal 1981, and $4.5 billion in President Reagan's latest fiscal 1982 request, according to the Labor Department documents.

The fiscal 1983 proposal would wipe out the remains of the Comprehensive Employment and Training Act (CETA) program and replace it with a much smaller private-sector program using up about $2.2 billion of the $3.4 billion in obligations; phase out or blend into a much smaller single fund the existing community service job program for older Americans, the summer youth job program and the special training programs for Indians and migrant workers; and sharply cut the Job Corps to an enrollment of 23,400, from more than 40,000 now.

The Department of Education, to meet OMB's guidelines, would have to cut its spending back to $7.7 billion, or a little over half the current $14.9 billion, Secretary Terrel H. Bell said yesterday. That would entail large new cuts in college student aid programs and the popular Title I program for disadvantaged elementary school students.

The Department of Housing and Urban Development reportedly intends to seek funds for only 100,000 new subsidized housing units for the poor. In most recent years more than 200,000 have been added; this year 150,000 will be.

The Environmental Protection Agency budget would be chopped 36 percent, according to leaked OMB documents, down to $700 million from the current $1.35 million. This would be on top of 16 percent cuts already made at EPA for 1982 and would be double EPA's own 1983 proposals that are already under fire in Congress as leaving the agency too little money to do its job. The hazardous waste control program would be reduced by 65 percent, pesticide regulation by 42 percent, and research by 38 percent, while outside contracting funds are cut 62 percent.

The Department of Health and Human Services, in an Oct. 26 confidential memo to budget director David A. Stockman reported in The Washington Post last week, outlined plans to cut $9.3 billion from welfare, Medicare and Medicaid.

At Reagan's request, Congress has already killed the CETA public service jobs program, under which the government gave states and local jurisdictions funds to hire the unemployed. The Labor Department budget memo contemplates phasing out in 1983 the large remaining CETA adult work-experience and training program with $200 million for wind-down obligations; and either phasing out or compressing into a single $200 million line item a number of other training programs that now have separate funding totaling much more.

The Job Corps would drop from the $553 million and 35,500 enrollment contemplated by the president for fiscal 1982 to $400 million and 23,400 enrollment for fiscal 1983. The memo calls for $112 million for trade adjustment training and $321 million for the Work Incentive Program, which provides training and job help to welfare clients.

In place of CETA, the memo says the department will seek $2.2 billion (although only half will actually be spent in fiscal 1983) for a new Business-Labor Training Program under which "consortia of private-sector employers and organized labor" would provide job training to targeted groups.

EPA administrator Anne M. Gorsuch met yesterday with Vice President Bush and Stockman in an effort to save her agency from what would be a reduction in purchasing power of more than 75 percent from President Carter's 1981 proposals. In a strongly worded letter to Stockman, Gorsuch reportedly warned that popular support for environmental programs nationwide would make the cuts boomerang against President Reagan.