Arizona Chemical - Executive Summary |
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The Arizona Chemical, Dover, Ohio facility has developed into a versatile multi-product facility, through improved technology that has allowed the plant to diversify with products used in making consumer goods that affect our everyday lives. The Dover plant produces key ingredients in a wide variety of applications such as lubricants and greases, candles, plastics, tires, soaps, cosmetic bath oils, shaving creams, skin creams, printing inks, and adhesives. Arizona Chemical supplies materials to companies such as Chevron, Noxell, 3M, Avon, Goodyear, DuPont, IBM, Texaco, Exxon, Kingsford, and Monsanto. Arizona Chemical has two chemicals that meet the 112(r) rule toxic chemicals threshold quantities (TQs); the chemicals are anhydrous ammonia ("NH3") and ethylenediamine ("EDA"). The TQ for NH3 is 10,000 lbs, while the TQ for EDA is 20,000 lbs. The NH3 is used in the solvent-separation plant portion of the facility as a refrigerant in the process. The EDA is used in the polyamide pro cess portion of the facility as a reactant in the process. Arizona Chemical is committed to handling all extremely hazardous substances safely to prevent their accidental release and to minimize the consequences of any such release. Management System Arizona Chemical has established a management system to oversee the implementation of its Risk Management Program responsibilities. The management system is designed to help ensure that each element of the program is fully and effectively completed. A qualified professional engineer has been assigned overall responsibility for the development, implementation, and integration of the program elements. Responsibility for implementing individual requirements of Arizona Chemical's program have been delegated to competent individuals. Record-keeping responsibilities are also included in the management system. Offsite Consequence Analysis (OCA) Requirements The Hazard Assessment portion of the 112(r) rule requires facility owners or operators to prepare "worst-case" and "alternative" release scenarios as appropriate to the operations. From the release scenarios, facilities are then to determine offsite impacts using specified offsite consequence analysis (OCA) parameters for worst-case releases and more realistic parameters for alternative releases. Release Scenarios: Arizona Chemical prepared worst-case release scenario analyses and alternative release scenario analyses for both NH3 and EDA, based on requirements given in the 112(r) rule. Worst-Case Release Scenarios: For NH3, we assumed a potential rupture of the NH3 tank and subsequent release of 10,000 pounds of NH3 as a gas in 10 minutes. For EDA, we assumed the potential collapse of the storage tank and release of all 80,000 pounds of slowly evaporating EDA into the containment dike, but one-third of its content s overflows the dike. The OCA for EDA was found to be less than NH3; therefore, based on the requirements of the 112(r) rule, the OCA for NH3 has been presented as the worst-case release. Alternative Release Scenarios: For NH3, we assumed a release of 960 pounds over 36 minutes from a potential line break between the inside NH3 liquid receiver and the main valve in the NH3 compressor building. For EDA, we assumed a 2,160 pound spill released over 2 minutes from a potential line separation from a coupling during a tank-truck unloading to the EDA tank. Again, we assumed that the EDA would evaporate slowly. Air-Impact Methods Inputs and Results The OCA of each chemical release was analyzed separately using appropriate air dispersion analysis and modeling techniques. Arizona Chemical used the most-recent version of several air dispersion models and modeling techniques which i ncluded the use of: equations given in the U.S. EPA RMP Offsite Consequence Analysis Guidance document; the U.S. EPA NH3 Refrigeration Model Plan; ALOHA (Areal Locations of Hazardous Atmosheres); and SLAB. Note that in worst-case and alternative OCA modeling parameters, "worst-case" meteorological conditions were used to simulate poor dispersion of the chemicals, even though the 112(r) rule allows the use of more favorable dispersion conditions, such as increased wind speeds and a greater dilution factor, for the Alternative Release Scenario analysis. The topography surrounding the Arizona Chemical operations will frequently contribute to poor dispersion conditions, especially at night and through early morning. Therefore, use of "worst-case" meteorology is prudent. Note that the areas potentially affected by an NH3 worst case release are above the Emergency Response Planning Guideline-Level 2 (ERPG-2). According to U.S. EPA , this level represents the "maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms which could impair an individual's ability to take protective action." The receptors in the potentially affected areas include: residences, schools, hospitals, major commercial and office and industrial areas. The population beyond the potentially affected area should not experience an impact level of concern (as defined by ERPG-2) from a NH3 release. The areas potentially affected by an EDA release (alternative release scenario) are above an air quality level that is one-tenth of the Immediately Dangerous to Life and Health (IDLH) value. The receptors in the potentially affected areas include residences. The population beyond the circle should not experience an impact level of concern (as defined by one-tenth of the IDLH value) from an EDA release. Accidental Release Prevention and Emergency Response Policies Backup safety systems, pressure relief valves, insulated vessels and piping, local emergency shut down systems, a containment dike for EDA storage, and a closed-loop system for NH3, are used to help mitigate the potential for leaks from the affected processes and equipment. Also, a perimeter monitoring system is used for the detection of NH3. Arizona Chemical has a preventative maintenance program in place along with work planning, safety checks and reviews, periodic inspections, and qualified maitenance personnel. To ensure safe operations, operators are trained and certified. Operations are continuously monitored by computer. Written procedures are in place and followed by operators. Internal and independant audits of the NH3 and EDA operations are performed. Five Year Accident History Two brief events have occurred at the Arizona Chemical facility involving less than 100 pounds of NH3 in one case and about 5 pounds in the other case. During each event, one worker was injured because of inhalation and/or skin contact with the NH3. No known offsite impacts occurred. Emergency Response Program An Emergency Response program has been developed and implemented as required for the purpose of protecting public health and the environment. In-plant emergency response consists of training to prepare for, prevent, respond to, and recover from emergencies. Those situations identified include hazardous material release, fire, explosion, floods, severe weather, and terrorism. A plant specific incident command system has been installed. The system is designed to be used for all types of emergencies, and is applicable to both small releases or minor fires and large-scale disasters. This system has established a chain-o f-command and assigned responsibilities in order to assess and respond to emergency situations. Plant-wide and community alarms are activated in the event of an emergency. In addition to in-plant emergency response events, a system has been established in order to notify outside personnel. Depending on the severity and type of event, facilities/agencies notified include, but are not limited to: Dover Union Hospital; local police, fire and ambulance service; Tuscarawas County Sheriff; Tuscarawas County Local Emergency Planning Committee; and, the Ohio Environmental Protection Agency. Planned Changes to Improve Safety Arizona Chemical has recently evaluated its safety systems and is considering additional changes to improve safety. We will continue to explore mitigation measures to protect the community and the environment from accidental releases. Implementation of effective mitigation actions will begin as soon as practicable. |