A Labor Department official yesterday revealed a list of tentative regulatory changes which, if implemented, could drastically shrink the scope of affirmative action enforcement, reduce the wage rates on public construction jobs and generally trim the agency's control over employers who do business with the government.

The administration wants to make government's regulation of business "more manageable and . . . more reasonable in its approach," and make sure that the benefits justify the costs, the official told reporters at a briefing. He allowed himself to be taped for radio broadcast but asked that his name not be used because the briefing was "on background."

The department's office of contract compliance programs, which polices job bias by all employers who do business with the government, is a major target of the regulatory review. The changes under consideration include:

A reduction in the number of companies covered by certain requirements, so that, for example, smaller contractors escape the need for a written affirmative action plan and other paperwork.

A reduction in paperwork and reporting requirements for all contractors.

Greater leeway in the requirement that employers hire minorities and women in the same proportions in which they are available in the work force.

Eliminating awards of back pay to affected employes as a remedy for an employer's failure to comply with the rules.

Elimination of numerical goals for minorities and females in construction.

According to an internal memorandum, officials are considering exempting contractors with fewer than 250 employes from preparing full affirmative action programs and exempting employers with exemplary records from review for as much as five years, The Wall Street Journal reported this week.

Labor Secretary Raymond J. Donovan has reached no decision on the proposals, the official emphasized yesterday, and they will be subject to final review by David Stockman's budget office. Officials hope to announce the new regulations by the end of June.

Civil rights groups view the changes as potentially crippling to equal employment opportunity efforts. "It will be devasting, if they do it," said Donna Lenhoff of the Women's Legal Defense Fund.

Business groups, on the other hand, have complained that the changes are not fundamental enough to be much help to them. Some have suggested among other things that President Reagan completely rewrite the executive order which authorized the affirmative action program. The Labor official said yesterday that "the administration has not rejected the possibility of a new executive order."

Of more immediate concern to some civil rights groups, Lenhoff said, is a move led by Rep. Robert S. Walker (R-Pa.) to outlaw the use of federal funds to enforce quotas. The House passed the measure this week as an amendment to a supplemental appropriation. In the past, the Senate has stopped such proposals, but it is feared that the newly conservative Senate this time will approve.