Washington ? The Bush administration quietly shelved a proposal to ban a gasoline additive that contaminates drinking water in many communities, helping an industry that has donated more than $1 million to Republicans.

The Environmental Protection Agency’s decision had its origin in the early days of President Bush’s tenure when his administration decided not to move ahead with a Clinton-era regulatory effort to ban the clean-air additive MTBE.

It said the environmental harm of the additive leaching into groundwater overshadowed its beneficial effects to the air.

The Bush administration decided to leave the issue to Congress, where it has bogged down over a proposal to shield the industry from some lawsuits. That initiative is being led by House Majority Leader Tom DeLay, R-Texas.

The Associated Press obtained a draft of the proposed regulation that former President Clinton’s EPA sent to the White House on its last full day in office in January 2001.

It said: “The use of MTBE as an additive in gasoline presents an unreasonable risk to the environment.”

The EPA document went on to say that “low levels of MTBE can render drinking water supplies unpotable due to its offensive taste and odor,” and the additive should be phased out over four years.

“Unlike other components of gasoline, MTBE dissolves and spreads readily in the groundwater … resists biodegradation and is more difficult and costly to remove.”

In 2000, the MTBE industry’s lobbying group told the Clinton administration that limiting MTBE’s use by regulation “would inflict grave economic harm on member companies.”

Three MTBE producers account for half the additive’s daily output.

The three contributed $338,000 to George W. Bush’s presidential campaign, the Republican Party and Republican congressional candidates in 1999 and 2000, twice what they gave Democrats, according to the Center for Responsive Politics. Since then, the three producers have given just over $1 million to Republicans.

The producers are Texas-based Lyondell Chemical and Valero Energy and the Huntsman companies of Salt Lake City.

A daily Washington newsletter disclosed the existence of the draft rule shortly after Bush’s inauguration.

At the direction of White House chief of staff Andrew Card and Mitch Daniels, then the White House’s budget director, all government agencies withdrew their pre-Inauguration Day draft regulations.

The EPA withdrew agency rules, including the MTBE one, in mid-February 2001, White House budget office spokesman Chad Kolton said.

In subsequent months, agencies rewrote many Clinton-era regulatory proposals and went public with them. The proposed MTBE regulation, however, never surfaced.

“As legislation looked more promising in 2002 and 2003, we focused our energies on supporting language in the Senate’s energy bill,” Jeffrey Holmstead, the EPA’s assistant administrator for air quality, said in a statement Friday.

The EPA favors a phaseout of MTBE through legislation. But the legislation has stalled, and it no longer calls for a ban in four years.

On their own, 17 states banned the additive, and dozens of communities are suing the oil industry.