Giving up on waiting for the Reagan administration to decide how it wants to rewrite the Clean Air Act, the Senate Environment and Public Works Committee has begun to draft its own bill.

The move reflects bipartisan annoyance with the White House's apparent inability to resolve continuing internal strife, as well as support for Chairman Robert T. Stafford (R-Vt.) in his effort to get action on the controversial issue this year.

Sources say the administration is divided over how much to loosen present air regulations and whether to give the states authority to set standards.

Some senatorial concern also is voiced that the administration may be trying a quiet end run around Congress by overhauling the law through regulatory revisions, meanwhile delaying action on the act itself.

Nine committee members instructed their staff at an informal session Thursday to prepare "a working paper" of legislative language on a list of specific issues for the 16-member panel to mark up when the Senate returns from its August recess.

"We'll consider an administration bill as far as possible when we get one," Stafford said in an interview. A hearing on any White House offering could be held the week of Sept. 21, he said.

The administration proposal was expected by June 30, but a leaked draft aroused such an outcry from environmental groups that the authors apparently went back to their notebooks. The administration recently has been passing the word on Capitol Hill that the air issue was held up until budget and tax battles were over, and now is next on the agenda.

But sources close to the drafting effort say that there is no agreement yet on several questions, and that Environmental Protection Agency Administator Anne M. Gorsuch is resisting pressures from elsewhere in the administration for a bill that would be looser in its restrictions -- and thus even more controversial -- than the leaked draft.

The sources said the disagreements concern automobile emission control requirements, whether to use economic considerations in setting pollution standards and what technological bases the standards should have. There is some effort within the Office of Management and Budget to delegate all standard-setting to the state level, but Gorsuch is said to oppose that approach.

"She may be holding the fort, but it's at a spot that still means no air program," said David Doniger of the Natural Resources Defense Council. He said fundamental administrative changes pendiing would accomplish some goals that might never pass Congress.

For example, he said, proposed changes in the definitions of what constitute "new" and "large" industrail plants would allow massive expansions of existing factories to avoid strict pollution control rules. Environment Committee staff members said speedy work on a bill could avoid some changes of that kind.

The environment committee staff was not instructed to draft new language on standard-setting methods, indicating that Stafford is satisfied with existing law on the question. The staff instead was told to rewrite the Clean Air Act requirements in nine areas: scientific review of pollution standards; preparation, approval and revision of state plans to meet the standards; compliance deadlines, technology and enforcement methods for industrial construction in below-standard areas; and visibility levels for measures to prevent significant deterioration of clean air.

Also, standards for new pollution sources; Hazardous chemical pollutants; interstate and international transport of air pollutants; enforcement and review procedures; and emission standards for new cars and trucks and compliance incentives for used vehicles.

Stafford said he won "something of a test vote" after a four-hour debate yesterday when Sen. John Heinz (R-Pa.) withdrew a proposed amendment to an approprations bill that would have relaxed auto emissions requirements. Stafford and others argued that Clean Air Act work should be done all at one time. "It was a considerable victory without having to fire a shot," he said.