Since June 1999, companies that store or manufacture hazardous substances have been required to develop a Risk Management Plan (RMP) that details safety precautions in the event of a catastrophe. The plan must be available to the public.
The studies consider the quantity of hazardous chemicals stored on site and the number of residents near the plant.
“Some people call those `death zones,’ ” said Amy Simpson of the Ohio Public Interest Research Group. “The industry prefers the more neutral term `circles of risk,’ but the standard term used by the EPA is `worst-case scenarios.’ ”
The chemical at Marathon Ashland that reportedly poses the potential for greatest risk to the public is hydrofluoric acid. The Canton refinery ranks 48th in the United States for its capacity to store 238,000 pounds of hydrofluoric acid, a substance used at the refinery since 1965 to make a gasoline additive. The U.S. EPA classifies the substance as a hazardous air pollutant. The Centers for Disease Control’s Agency for Toxic Substances and Disease Registry lists hydrogen fluoride — which becomes hydrofluoric acid when dissolved in water — as harmful or fatal at high levels.
Even low levels can burn the eyes and skin.
In 1969, six Ashland employees required hospital treatment after an accident with hydrofluoric acid. According to company spokesman Troy Reynolds, records indicate four workers were injured in accidents involving the chemical between 1969 and 1988. The reports classify the accidents as “serious” but do not describe the injuries or mention whether the workers were hospitalized.
Using software available from the EPA to calculate variables including air temperature and other weather conditions, and weight and amount of the substance, Simpson computed worst- and alternate-case scenarios for the Canton refinery. By her calculations, the release of the entire store of hydrofluoric acid held at Marathon Ashland could affect areas up to 16 miles from the refinery. The RMP determined by the refinery said a release could spread over a 25-mile radius.
In a written statement from Marathon Ashland, the company said its assumptions included that “the largest vessel of HF acid catastrophically fails and releases all of its contents in 10 minutes, we cannot use any of our safety systems to stop the release, and worst-case weather conditions are used for the modeling, i.e., no wind. Thus, the scenario is very unlikely.”
Marathon Ashland installed a hydrofluoric acid suppression system last month as a condition of its 1998 consent decree with the U.S. EPA. Reynolds said it cannot be determined whether that system would have prevented any of the previous accidents.