South Dakota Water Science Center
USGS IN YOUR STATE
USGS Water Science Centers are located in each state.
Environmental Behavior and Fate of Methyl tert-Butyl Ether (MTBE)Paul J. Squillace, James F. Pankow, Nic E. Korte, and John S. Zogorski
U.S. Geological Survey, 1608 Mt. View Road, Rapid City, South Dakota 57702
Phone (605) 355-4560 ext. 239, Telecopier (605) 355-4523, firstname.lastname@example.org
When gasoline that has been oxygenated with methyl tert-butyl ether (MTBE) comes in contact with water, large amounts of MTBE can dissolve; at 25 degrees Celsius the water solubility of MTBE is about 5,000 milligrams per liter for a gasoline that is 10 percent MTBE by weight. In contrast, for a nonoxygenated gasoline, the total hydrocarbon solubility in water is typically about 120 milligrams per liter. MTBE sorbs only weakly to soil and aquifer materials; therefore, sorption will not significantly retard MTBE's transport by ground water. In addition, MTBE generally resists degradation in ground water. The half-life of MTBE in the atmosphere can be as short as 3 days in a regional airshed. MTBE in the air tends to partition into atmospheric water, including precipitation. However, washout of gas-phase MTBE by precipitation would not, by itself, greatly alter the gas-phase concentration of the compound in the air. The partitioning of MTBE to precipitation is nevertheless strong enough to allow for up to 3 micrograms per liter or more inputs of MTBE to surface and ground water.
1996, U.S. Geologcial Survey Fact Sheet, FS-203-96, 6 p.