In response to mounting public concern, several studies were commissioned by the state Legislature to review closely the health, environmental and economic impacts of MTBE's use in California's Cleaner Burning Gasoline program. The University of California-Davis has
released a report, Health and Environmental Assessment of MTBE, that documents the risks and costs associated with MTBE's use.
The report examined contamination of groundwater, public wells and surface water reservoirs by MTBE, noting that if MTBE continues to be used at current levels, "the potential for regional degradation of water resources, especially groundwater basins, will increase." The costs of cleanup, as estimated by the report, range from $340 million to $1.5 billion. Alternatives to MTBE, such as ethanol, present minimal danger to water supplies and would have much lower clean-up and monitoring costs, the report finds.
A report entitled, Supply and Cost of Alternatives to MTBE in Gasoline, has been completed by the California Energy Commission that reviews the economic and logistical impacts of discontinuing the use of MTBE in the state. According to the study, alternative oxygenates could replace demand currently met with MTBE given a sufficient transition period. "Suppliers appear to have the production capacity and raw materials necessary to produce sufficient volumes of ethanol, ETBE and TBA under any of the various cases," the report concludes.
ETBE is Ethyl Tertiary Butyl Ether, which is a colorless, flammable liquid produced from ethanol and isobutylene. It contains octane-enhancing properties when added to gasoline. TBA is tertiary butyl alcohol. TBA is generally added to gasoline to increase octane levels.
