The Senate Environment and Public Works Committee yesterday voted out a bill to reauthorize the Clean Water Act, but left the way open for later committee amendments to resolve two remaining sticky issues.

The legislation was approved on a 12-to-0 vote after Sen. John H. Chafee (R-R.I.) agreed to give Sen. Steve Symms (R-Idaho) one more chance to win approval of a controversial provision to allow municipalities the right to "opt out" of national standards for industrial wastes.

Symms, who has the fervent support of industry and municipal water officials, will attempt to work out a compromise with the Environmental Protection Agency, which has argued that the "opt out" provision would be difficult to manage and enforce.

Industry officials called it a "stutter step" but an encouraging one. Enviromentalists, who oppose the "opt out," said they were confident that Symms "will run into discouraging news from EPA."

The committee also agreed to withdraw a provision designed to address the problem of pollution from non-specific sources, such as runoff from agricultural lands and construction sites, until a hearing is held on its potential impact on farmers and ranchers.

The provision, offered by Sen. David F. Durenberger (R-Minn.), would restrict government subsidies of such pollution sources. Opponents worried that the provision could cut off Farmers Home Administration loans to farmers or make them ineligible for the government's payment-in-kind program.

In another change, supported by both industry and environmentalists, the committee extended the life of permits under the act to 10 years, instead of five, but stipulated that permits must be renegotiated if federal or state water-quality standards are tightened.