When President Bush announced plans for a new national energy policy in 2001, he probably never gave a thought to a gasoline additive now familiar to every member of Congress and energy lobbyist.

Methyl tertiary butyl ether.

If that doesn’t quite roll off the tongue, it’s MTBE for short.

It can’t compete with Michael Jackson and the Iraqi occupation as front-page news, but MTBE is suddenly making headlines as the unlikely roadblock to congressional passage of a far-ranging energy bill currently stalled in the Senate.

Heretofore, MTBE has been a relatively obscure fuel additive, but one with a deserved Jekyll-and-Hyde reputation among those familiar with it.

It has done an admirable job in helping reduce polluting tailpipe emissions from vehicles since being put in reformulated gasoline in the mid-1990s. Prior to that, it was used as an octane enhancer after lead was removed from gasoline.

But MTBE, the “Houdini of pollutants,” also has a nasty habit of leaking out of underground gasoline storage tanks and contaminating water supplies. It can render water undrinkable by giving it a bitter taste and foul odor.

As of this writing, the pork-laden energy bill is stalled over the issue of whether chemical and oil companies that manufacture MTBE and use it in making gasoline should be exempt from liability claims that it is a “defective product.”

The exemption would not preclude claims that MTBE contamination resulted from spills or other negligence.

It might seem amazing that the MTBE issue could hold up a bill brimming with tens of billions of dollars in tax breaks and spending measures affecting the oil industry, coal producers, automakers, electric utilities and others.

But the MTBE standoff isn’t surprising given the major players involved and the billions of dollars in liability claims potentially at stake.

Just last week, the California city of Santa Monica announced a huge settlement of litigation over MTBE contamination that resulted in the coastal community’s losing half its supply of drinking water. The defendants include Shell, ChevronTexaco, ExxonMobil and Unocal.

They will pay to build and operate a treatment facility to clean up the city’s ground water at a cost that could reach $400 million, the Los Angeles Times reported. The city also will receive an additional $92.5 million.

California, New York and other states are phasing out MTBE as a gasoline additive. The national energy bill calls for it to be phased out by about 2015.

House Majority Leader Tom DeLay, R-Texas, and U.S. Rep. Joe Barton, R-Texas, have unrelentingly insisted that the MTBE liability waiver be included in the bill. Texas and Louisiana are centers for MTBE manufacturing, and Houston-based Lyondell Chemical is a leading producer.

Proponents of the liability waiver rightly argue that Congress pressured the energy industry in the early 1990s to make an oxygen additive and that MTBE was, for several reasons, preferred over ethanol — a fuel additive made from corn.

But opponents of the liability exemption say oil and chemical companies knew years before of the dangers of MTBE pollution of water supplies.

Opponents of the waiver include the American Waterworks Assn. and the National League of Cities, whose members fear they could be stuck with huge bills for cleaning up MTBE-contaminated water if the waiver is approved.

If DeLay and other Republican leaders want the energy bill to move forward, they should drop their insistence on the liability waiver. Liability issues should instead by decided by judges and juries, or out-of-court settlements.

Congress, meanwhile, should seriously re-examine whether it wants to — as the energy bill proposes — greatly expand the use of ethanol as an oxygen additive for gasoline as MTBE is phased out.

Critics say expanded ethanol use would increase retail gasoline prices, raise production and transportation costs for refiners, possibly cause gasoline supply disruptions and provide marginal environmental benefits. They say ethanol has strong political legs only because of vocal backers from corn-producing states.

A better solution might be simply to drop the requirement for an oxygen additive in gasoline and compensate by adopting other pollution-reducing measures, such as requiring more fuel-efficient and cleaner-burning vehicles.