Hercules Incorporated - MCW Plant - Executive Summary |
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I. Accidental Release Prevention and Emergency Response Policies Hercules Incorporated's Missouri Chemical Works (MCW) Plant is committed to being an asset to its community. Management makes every effort to ensure both employee safety and community safety by being proactive in complying with federal, state and local regulations. For example, in 1997, a waste heat boiler was brought on line to comply with Clean Air Act (CAA) regulations, which called for use of a flare or an alternative method to burn gases. MCW installed a system that not only burns the gases better than a flare, but also allows for the recovery of energy. In addition, MCW has formed a community advisory panel (CAP) to encourage the exchange of ideas and information between MCW officials, business leaders and concerned citizens. CAP meetings are held on a regular basis to keep the public informed of MCW activities and to gather and address any concerns raised by the community. II. Facility Description and Regul ated Substances Handled The Hercules MCW Plant is a chemical manufacturing plant located in Louisiana, Missouri that manufactures formaldehyde, pentaerythritol (PE), nitroform, synthetic lubricant and provides its own utilities. Besides formaldehyde, the plant handles two other substances regulated by the risk management provisions (RMP) of 40 CFR 68: acetaldehyde and chlorine. Acetaldehyde, a flammable, is used as a reactant in the PE process. Acetaldehyde is pumped from a railcar or tanker truck into one of six storage tanks. From the tanks, acetaldehyde is pumped to the weigh tank, which is used to ensure a set amount of acetaldehyde is charged to the PE reactor. The maximum amount of acetaldehyde in the RMP covered process is approximately 160,000 gallons with the largest vessel in the process being a 30,000-gallon storage tank. Chlorine is used in water treatment activities at the plant including process water, soft water and cooling tower water disinfection. It is receive d in either 150-pound cylinders or 1 ton cylinders and is stored at various locations throughout the plant. The areas storing the 150 pound cylinders are not considered RMP regulated processes because each area stores at a maximum 10 cylinders or 1500 pounds of chlorine. The areas are also isolated from one another so that an accident in one area will not trigger a release in another area. However, the one ton cylinders stored and used at the water filtration plant do trigger RMP requirements as the maximum amount of chlorine in the RMP covered process is about 10,000 pounds. This chlorine is used to disinfect process water used for operations throughout the plant and soft water used as boiler feed by the powerhouse. The plant keeps at most five 1 ton cylinders in the chlorine storage and supply building. Of these five cylinders, one is actively being used and another is connected to the same chlorination station as backup. Formaldehyde is manufactured by burning methanol over a silver catalyst in three converters. The exiting vapor stream is condensed, routed through an absorption column and distilled to remove the majority of unreacted methanol. The formaldehyde solution is stored in one of seven tanks. The largest tank has a capacity of 200,000 gallons and is typically used to supply raw material for PE production or for Nitroform production. Formaldehyde is stored at the plant in various concentrations. The maximum amount of formaldehyde solution stored in the formaldehyde RMP covered process is typically no more than 340,000 gallons. III. Worst-Case and Alternative Release Scenarios The worst case release scenarios for all the regulated substances at the MCW Plant were identified using the guidelines set forth in the RMP regulations of 40 CFR 68. The largest vessel of each process was assumed to explode as a vapor cloud for the flammable, acetaldehyde, or to spill its contents in 10 minutes for the worst case toxic, chlorine. Impact distances f or the worst case releases were calculated using EPA approved models. Due to MCW's emphasis on safe management and operating procedures, it is highly unlikely that one of the worst case scenarios would actually occur. The accidents described below for each RMP regulated substance are more likely to occur. These accidents were identified based on previously occurring incidents or based on plant personnel knowledge of the processes. The acetaldehyde alternative release scenario assumes that the contents of a 30,000-gallon tank spill to a diked area forming a pool. The pool then ignites resulting in a pool fire. The dike serves to limit the surface area available to burn. The Automated Resource for Chemical Hazard Incident Evaluation (ARCHIE) model was used to determine the impact distance of 0.05 miles due to the pool fire. This scenario does not result in an offsite impact, and it was determined that no other scenarios involving the tank would result in an offsite impact either . The alternative chlorine release chosen was damage done to a fusible plug of a one ton cylinder. It was assumed that the entire contents of the cylinder are released but because the size of the escape area is much smaller than in the worst case scenario, the release duration is longer. ARCHIE was used to determine the release rate due to the damaged plug. The release rate was then entered into the Dense Gas Dispersion (DEGADIS) model to determine the actual impact distance of 0.44 miles due to the release. This type of release from a 1 ton chlorine cylinder could effect approximately 70 people. Formaldehyde not used in the plant is transferred to trucks and sold as product. The alternative case scenario involves a loading pump used in this transfer spilling 50% formaldehyde solution to the ground at full speed for 10 minutes before it is shut down. The ARCHIE model was used to estimate the surface area of the spill and the resulting evaporation rate from the pool. The evapo ration rate was then entered into the DEGADIS model to determine the impact distance of 0.36 miles resulting from the spill. A formaldehyde spill of this magnitude could effect a population of approximately 70. IV. General Accidental Release Prevention Program and Chemical-Specific Prevention Steps MCW is in compliance with all applicable federal, state and local regulations. Accidental release and emergency response specific regulations are discussed below. MCW has three processes subject to the accidental release regulations of 40 CFR 68. Based on the North American Industry Classification System (NAICS) codes for these processes and the fact that the modeled impact distances extend to off-site receptors, all three RMP regulated processes at MCW are classified as Program Level 3. These RMP regulated processes are also subject to Occupational Safety and Health Administration's (OSHA) Process Safety Management (PSM) provisions. These provisions were developed to ensure the saf ety of workers by requiring, among other things, the development of and training on standard operating procedures, the identification of hazards associated with facility operations and the development of a system for employee participation in PSM compliance. By complying with OSHA's PSM standards, MCW is complying with the Prevention Program elements of the RMP regulations. OSHA as well as the Clean Water Act (CWA), the Oil Pollution Act (OPA), the Resource Conservation and Recovery Act (RCRA) and the Emergency Planning and Community Right-To-Know Act of 1986 (EPCRA) require the development of emergency response procedures in case of an accident. MCW's Spill Prevention Control and Countermeasure Plan (SPCC) and Best Management Practices Plan (BMP) address actions to take to prevent a discharge of an oil or hazardous substance and actions to take in case a discharge occurs. The Emergency Control Plan provides procedures for employees to follow in response to various types of emergen cies that may occur at the plant. All three of these emergency response plans were developed to meet the regulations listed above. V. Five-Year Accident History Hercules Incorporated has had no accidental releases of acetaldehyde, chlorine or formaldehyde from covered processes that have resulted in offsite injury, death or environmental damage resulting in response or restoration activities to date. VI. Emergency Response Program As discussed in Section IV, MCW uses two emergency response plans to combat potential accidents: the SPCC/BMP Plan and the Emergency Control Plan. The plans address plant security, notification procedures, response procedures, employee training including drills, a list of available response equipment, preventative maintenance procedures and good housekeeping practices. Access to MCW is controlled 24 hours a day through one main entrance gate. The rest of the plant is surrounded by a barbed wire topped chain link fence other than a contractor entra nce, which is also under the control of the main gate. MCW coordinates emergency response efforts with the Pike County Local Emergency Planning Committee. Notification of the local emergency response agencies is outlined in the emergency response plans. General response procedures for all personnel and more specific requirements for MCW response personnel are depicted in the plans. Employees are trained on these notification procedures as well as on other actions to take in response to an incident. The emergency response plans are reviewed annually with employees as part of the monthly safety meetings held by the Safety Department. In addition, hazards associated with processes are discussed in the Right-to-Know training provided to all MCW employees. Contractors receive a Safety Orientation course prior to being allowed to work on MCW property. Training drills are conducted at least annually to help keep employees aware of their rolls during an emergency incident. MCW pers onnel have participated in every planned exercise held by the Local Emergency Planning Committee. Two drills have been hosted by the MCW plan and either simulated release of an RMP chemical or were related to preventing release of an RMP chemical. In addition to emergency response procedures, the plans address procedures to help prevent accidents such as equipment and area inspection schedules and discussions at monthly safety meetings on ways to keep work areas clean and therefore accident free. VII. Planned Changes to Improve Safety A schedule is in place to increase the frequency of Emergency Response Team drills to a minimum of one per quarter. This increase will provide more experience and heighten the preparedness of the Emergency Response Teams and their ability to deal with emergency situations. Future plans include the addition of a software system to perform Process Hazard Analyses to identify, evaluate, and control hazards within the plant. |