House and Senate negotiators working on an energy bill have omitted from draft legislation a measure providing legal protection for producers of the gasoline additive MTBE, officials said yesterday.

The reason is that Senate negotiators are refusing to accept a House measure to shield manufacturers of the additive from product defect lawsuits -- a provision that helped lead to the demise of energy legislation in 2003.

Rep. Joe Barton (R-Tex.), who chairs the conference committee trying to resolve differences in the House and Senate bills, told reporters that he may seek to amend the legislation today to include legal protection for MTBE, or methyl tertiary-butyl ether. But he acknowledged that Senate negotiators so far have refused to accept it.

Barton said he expects the conference committee to complete its work today. Separate negotiations are taking place behind closed doors to resolve differences between the House and Senate bills over billions of dollars in tax breaks for the energy industry. Lawmakers said they expect final votes on the energy bill in the full House and Senate before their August recess.

MTBE has been widely used in gasoline as a way to reduce air pollution. But it has seeped from underground storage tanks, polluting drinking water nationwide.

Barton and other supporters have said manufacturers are entitled to legal protection because the federal government required that additives be used. Opponents said extending that legal protection would require taxpayers to pay for billions in cleanup costs.

Barton sought to bridge differences between the House and Senate on Friday by offering a plan that would provide legal protection but also create an $11.4 billion fund to decontaminate water and pay other compensation. The plan would have required the oil industry to pay about a third of the costs and federal and state governments to pay the rest.

Supporters could offer an amendment to the cleanup plan.

It is "a matter of whether the amendment is going to be accepted or not," said Bill Wicker, a spokesman for Democrats on the Senate Energy and Natural Resources Committee.