EPA has a responsibility under section 112(r) of the Clean Air Act Amendments of 1990 for the prevention and mitigation of accidental releases. One of the fundamental ways to prevent accidents is to understand why accidents occur and to apply the lessons learned to prevent future incidents. Consequently, EPA has a responsibility to investigate and understand why certain chemical accidents have occurred. A key objective of the EPA chemical accident investigation program is to determine and report to the public the facts, conditions, circumstances, and causes or probable causes of chemical accidents that resulted, or could have resulted, in a fatality, serious injury, substantial property damage, or serious off-site impact, including a large scale evacuation of the general public. The ultimate goal of the accident investigation is to determine the root causes in order to reduce the likelihood of recurrence, to minimize the consequences associated with accidental releases, and to make chemical production, processing, handling, and storage safer. This report is a result of an EPA investigation to describe the accident, determine root causes and contributing factors, and identify findings and recommendations.