The time has come for an MTBE Remediation Handbook. There are hundreds of thousands of spills of gasoline containing MTBE in the United States. More than a billion dollars are spent each year to clean up spills of gasoline and manage the risk from existing contamination. Staff of the appropriate regula­ tory authorities within each state must make decisions to manage these spills on a site-by-site basis. Do they require active cleanup? How much cleanup is necessary? What is the most appropriate technology? What performance should be expected from the available technology? If the state regulators provide good answers to these questions on a site-by-site basis, the money will be well spent. This handbook is concerned with remediation of MTBE in existing spills. There are a number of myths about MTBE that act as impediments to effec­ tive remediation and risk management for MTBE. These myths present MTBE as being qualitatively different from petroleum hydrocarbons. Many still think that benzene is biodegradable in ground water while MTBE is not, that risk management is appropriate for benzene and not appropriate for MTBE, and that drinking water can be treated to remove benzene but not to remove MTBE. These myths have made us reluctant to deal with existing MTBE contamination. As is documented in this MTBE Remediation Handbook, we have the technology to clean up MTBE in a rational and economic man­ ner.