Boating and MTBE
The marine industry fully supports the Environmental Protection Agency's (EPA) recommendation that the use of Methyl Tertiary-Butyl Ether (MTBE) in gasoline be reduced and that alternatives to MTBE be brought into widespread use.
MTBE is a gasoline additive that was designed to increase octane levels and meet minimum oxygen requirements established by state and federal air quality regulations. Currently, 16 states mandate the use of MTBE reformulated gasoline. The intention of adding MTBE to gasoline was to reduce carbon monoxide and hydrocarbon emissions from gasoline, thus promoting cleaner air and cleaner water.
In 1998, the EPA appointed a Blue Ribbon Panel to investigate the possibility that MTBE was posing risks to water bodies. The EPA never intended to have cleaner air at the expense of water quality.
In July 1999, the EPA Blue Ribbon Panel found that there is no significant additional air quality benefit to be gained by continuing to use MTBE in reformulated gasoline. In fact, there are significant risks to groundwater and surface water contamination with its continued use. The panel recommended that the use of MTBE must be significantly reduced as soon as possible without sacrificing the gains made in achieving Gleaner air.
The panel further found that the most significant source of groundwater contamination by MTBE were releases from underground gasoline storage systems (UST). Although many of these systems have been upgraded over the last decade, about 20 percent have not, and there continue to be reports of releases due to inadequate design, installation, maintenance and/or operation. In addition, the EPA does not currently regulate many fuel storage systems (e.g., farms, and small aboveground tanks). Beyond groundwater contamination from UST sources, the other major source of water contamination appears to be small and large gasoline spills to ground and surface waters.
Recreational watercraft, particularly those with older motors, are also a source for releasing MTBE in surface water bodies, although on a much lesser scale than UST and fuel spills. According to the National Marine Manufacturers Association, the new engine technologies that are responsible for significant reductions in the release of hydrocarbon emissions will also reduce the release of MTBE. The fact remains, however, that no matter how clean an engine is, whether it is in a boat, automobile, motorcycle or even a lawnmower, it will continue to release some MTBE in its emissions until the MTBE is removed from gasoline supplies.
