In-situ Remediation of MTBE Using OxyVac Technology Steve Jones, PhD Jerry L. Wolf James Keegan REA Methyl-tert-butyl ether (MTBE) has been used in California as a fuel additive to increase the oxygen content of gasoline since 1989, to meet State and Federal clean air regulations.  This reformulated gasoline is required to contain no less than 2.7% oxygen, which is equal to 15% MTBE by volume.  The Environmental Protection Agency (EPA) has tentatively classified MTBE as a possible human carcinogen, and in February of 1991, the California EPA office of Environmental Health Hazard Assessment (OEHHA) established an interim action level of 35 parts per billion (ppb) for MTBE.   Methyl-tert-butyl ether (MTBE)  is a colorless, flammable liquid with a turpentine-like odor, is highly soluble and extremely volatile.  MTBE is a dangerous groundwater contaminant because of it’s mobility and resistance to biodegradation in either aerobic or anaerobic conditions.  MTBE will essentially move at the same rate as groundwater, due to its tendency not to adsorb onto the vadose zone material.  Groundwater in equilibrium with gasoline containing 15% MTBE could contain as much as 9,600 parts per million (ppm) MTBE. DOWNLOAD FULL-TEXT IN PDF