How Does MTBE Contamination Occur?
MTBE has a somewhat high vapor pressure (313 Torr @ 30C) and high solubility in water (4.8% @ 20 C). Because of this MTBE easily transfers to air or to drinking water. Compared to benzene, a major component in gasoline, MTBE diffuses 8.6 times faster in water. It is also 28 times more soluble in water than benzene. In other words, MTBE gets into groundwater more readily than benzene and it spreads more rapidly. MTBE leakage occurs whenever gasoline that is reformulated with it leaks. Leaks from gas station storage tanks and lines, automobile gas tanks, watercraft, lawnmowers, snowmobiles, tractors and portable storage canisters all can be sources of MTBE contamination.
