American Pacific Corporation, Utah Operations - Executive Summary |
|
EXECUTIVE SUMMARY 1. The accidental release prevention and emergency response policies: American Pacific Corporation Utah Operations (AMPAC) is dedicated to preventing chemical emergencies. AMPAC has several divisions in its Utah operations. The divisions are contiguously located on AMPAC property. The facility handles anhydrous ammonia and propane, both of which are considered hazardous by EPA. AMPAC's WECCO division manufactures oxidizers and AMPAC's American Azide division manufactures sodium azide. Anhydrous ammonia is an essential ingredient in ammonium perchlorate. Anhydrous ammonia is a key ingredient in sodium azide. Ammonium perchlorate is a critical component for the defense of our country and is an important ingredient in space program for both manned and unmanned vehicles. Sodium azide is the prime agent in many air bags that supplies the nitrogen to inflate the air bags and save lives. Ammonia is a toxic substance that is widely used in households in limited con centrations. Propane is used at AMPAC to provide building heat and to generate steam. Steam is a necessary element in our process providing heat to be able to form the products that we make, preventing winter freezing of process lines and systems and heating most of our buildings. Propane is a flammable substance. The very properties that make it hazardous are the same properties that make it valuable. For both ammonia and propane, it is necessary to observe certain safety precautions to prevent unnecessary human exposure, to reduce the threat to our own personal health as well as that of our coworkers, and to reduce the threat to nearby members of the community. At AMPAC, it is our policy to adhere to all federal, state, and local regulations. Safety depends on the manner in which we handle ammonia and propane combined with the safety devices designed into the systems. Our procedures for handling the materials and the training that we have provided to our employees reduce the possibility of an accident. AMPAC administratively limits the fill ratio of the ammonia tanks to 80% in the perchlorate process, the fill ratio of ammonia tanks in the sodium amide process to 85%, and the fill ratio of the propane tanks to 86.667%, all in accordance with good safety practices for the vessels. AMPAC Senior management has devoted many resources to training our employees to be capable of responding to any situations that could be hazardous and believes the response training is also integral in preventing incidents. An AMPAC manager has been supported in acting as a member of the Iron County local Emergency Planning Committee. AMPAC has also provided training to local and state responders to increase their familiarity with our materials and increase public safety in the event that an emergency occurs with any of the products we produce even if they were manufactured by a competitor. The AMPAC facility was intentionally constructed away from town to minimize any effec ts if an incident did occur. AMPAC believes the public recognizes its commitment to be a good citizen of the community based on its community involvement and its care in the design and operation of the plant to protect the community. 2. The stationary sources and regulated substances handled: AMPAC has two EPA Risk Management Plan regulated substances on site. These are anhydrous ammonia and propane. AMPAC has two anhydrous ammonia tanks at the WECCO division, which can contain 82,400 pounds of ammonia each. Ammonia can be received by truck but is normally received by rail. A rail car may contain up to 180,000 pounds of ammonia. The ammonia is used in three ammonium chloride reactors. Ammonia is transported via pipeline within the facility. AMPAC has two anhydrous ammonia tanks at the American Azide division, which can contain 131,402 pounds of ammonia each. Ammonia can be received by truck but is normally received by rail. A rail car may contain up to 180,000 pounds of amm onia. The ammonia is used in sodium amide reactors. Ammonia is transported via pipeline within the facility. AMPAC has four propane storage tanks that can contain 109,356 pounds of propane each. In addition, three individual building tanks can contain 3,645 pounds of propane each. These tanks are used to supply building heat. While it is possible to receive propane by rail car, no propane has been received by rail in over five years therefore a railcar has not been included as a potential on site source for offsite consequence analysis. If railcars are used in the future, AMPAC will modify its RMP plan accordingly and submit a revision to EPA. Propane at AMPAC is received by truck. Propane at the facility is transported from storage to use points (boilers or building heaters) by pipeline. 3. Facility description, Worst Case Release Scenarios, and Alternate Case Release Scenarios AMPAC is a facility that manufactures specialty oxidizers in its WECCO division facility. These oxidizers are used in a variety of end uses spanning everything from providing the oxygen for rocket motors (ammonium perchlorate) to enhancing traffic safety with materials in road flares and air bags (potassium perchlorate). The facility begins its operation with ordinary table salt (sodium chloride) dissolved in water. Electrolysis turns this salt into sodium hypochlorite (laundry bleach), then into sodium chlorate (which is commonly used in the pulp and paper industry), and then finally into sodium perchlorate. Some of our customers use sodium perchlorate directly either in solution or dry form. Sodium perchlorate is used for everything from electro-machining to adding other materials to it to form a slurry explosive. From this point, either potassium chloride or ammonium chloride can be reacted with sodium perchlorate to form potassium perchlorate (used in air bags and road flares and also has been used medically) or ammonium perchlorate (primarily used in the defense and s pace programs as a means to provide the oxygen source for a rocket motor). Ammonia is reacted with thirty two per cent hydrochloric acid to form ammonium chloride. The ammonium chloride is used in the process to react with sodium perchlorate to form ammonium perchlorate and sodium chloride. Ammonia is piped from the receiving stations into the two storage tanks. Pipelines also carry ammonia from the tanks to three ammonium chloride reactors. The total amount of Ammonia at the AMPAC facility is 344,800 which will last from about 11 to 21 days depending on operating levels. Since this material arrives by rail, this is a very limited inventory. Propane is primarily used to manufacture steam to provide process heat (warming up solutions and drying crystals) and also to provide building heating and pipeline freeze protection. Steam manufactured in this method is used at all of AMPAC Utah operations except in the Halotron and AMPAC farms divisions. Propane is piped from the receivin g station into the storage tank. Propane is also piped from the storage tanks to its use points. The total amount of propane on site is 448,360 pounds. If the facility is operating at capacity and using only propane for fuel, this quantity will last about 9 days. AMPAC is a facility that manufactures specialty oxidizers in its WECCO division facility. These oxidizers are used in a variety of end uses spanning everything from providing the oxygen for rocket motors (ammonium perchlorate) to enhancing traffic safety with materials in road flares and air bags (potassium perchlorate). The facility begins its operation with ordinary table salt (sodium chloride) dissolved in water. Electrolysis turns this salt into sodium hypochlorite (laundry bleach), then into sodium chlorate (which is commonly used in the pulp and paper industry), and then finally into sodium perchlorate. Some of our customers use sodium perchlorate directly either in solution or dry form. Sodium perchlorate is us ed for everything from electro-machining to adding other materials to it to form a slurry explosive. From this point, either potassium chloride or ammonium chloride can be reacted with sodium perchlorate to form potassium perchlorate (used in air bags and road flares and also has been used medically) or ammonium perchlorate (primarily used in the defense and space programs as a means to provide the oxygen source for a rocket motor). Ammonia is reacted with thirty two per cent hydrochloric acid to form ammonium chloride. The ammonium chloride is used in the process to react with sodium perchlorate to form ammonium perchlorate and sodium chloride. Ammonia is piped from the receiving stations into the two storage tanks. Pipelines also carry ammonia from the tanks to three ammonium chloride reactors. The total amount of ammonia at the WECCO division is 344,800 pounds which will last about 21 days depending on operating levels. Since this material arrives by rail, this is a very limi ted inventory. AMPAC manufactures sodium azide in its American Azide division facility. Sodium azide is primarily used in automotive air bags however it also has essential uses in pharmaceutical manufacture. Sodium azide has also been used as a blood pressure controlling medication. The facility process starts with the reaction of anhydrous ammonia with sodium metal to form sodium amide. The sodium amide is then reacted with nitrous oxide to form sodium azide and sodium hydroxide. There is ammonia present in the sodium azide reactors. All excess ammonia that can not be recycled to the process is scrubbed with water. The resultant water solution is excellent fertilizer and is used at AMPAC Farms. The American Azide division aqua ammonia is not of sufficient concentration to be considered hazardous under the EPA RMP regulation. The division has the capability to increase the ammonia concentration to the EPA hazardous point. AMPAC Utah Operation has never made aqua ammonia in a concentration that would trigger the EPA hazardous classification and in fact has part of that process area piping removed and blinded to preclude ever doing the aqua ammonia upgrade operation inadvertently. Ammonia is piped from the receiving stations into the two storage tanks. Pipelines also carry ammonia from the tanks to twelve sodium amide reactors. The total amount of Ammonia at the AMPAC American Azide division is 406,696 pounds, which will last about 28 days depending on operating levels. Since this material arrives by rail, this is a very limited inventory. Combining the quantities in the two processes, AMPAC may have as much as 749,486 pounds on site at the various divisions facilities. AMPAC's WECCO division uses Propane primarily to manufacture steam to provide process heat (warming up solutions and drying crystals) and also to provide building heating and pipeline freeze protection. Steam manufactured in this method is used at all of AMPAC Utah Operations except i n the Halotron and AMPAC farms divisions. Propane is piped from the receiving station into the storage tank. Propane is also piped from the storage tanks to its use points. The total amount of propane on site is 448,360 pounds. If the facility is operating at capacity and using only propane for fuel, this quantity will last about 9 days. AMPAC has prepared three worst-case scenario analyses, one for propane and two for ammonia. The criteria of these analyses are set by EPA and assume that absolutely everything that could prevent problems fails for the largest storage container on site. Since the largest storage container is a railcar for both ammonia processes, the results of the worst case scenario are the same for both cases. For this reason the calculation result is only listed once below in the executive summary. The ammonium chloride process rail car receiving station is 0.3 miles from the nearest public receptor ( a Questar gas metering compound) and the sodium amide pro cess rail car receiving station is 0.2 miles from the two nearest public receptors ( the Questar compound and the Union Pacific railroad tracks). In the case of a toxic material, the scenario requires that every bit of material in the container be released across a ten minute interval, a standard set of meteorological conditions is used, and a circle radius is calculated out to an EPA determined concentration based on the emergency response planning guide (ERPG). EPA has provided a set of guidance tables to conduct offsite consequence analysis. These tables have been used to develop software publicly available over the internet that is known as RMP*Comp Ver. 1.06. This software (available from the EPA website) was used to determine the consequence analysis. The scenario required to be used was the rupture of an incoming supply rail car of anhydrous ammonia. Suppliers limit the fill ratio of ammonia cars in the size we purchase to 73 metric tons or 160,936 pounds. AMPAC does not control maintenance on the railcar but has carefully selected its suppliers to obtain a high quality feedstock from manufacturers who care about the quality of their products and the containers in which they ship. The suppliers must also meet Department of Transportation requirements to ship the ammonia over the rail lines. These facts make the selected worst case scenario unlikely. The results of the consequence analysis appear below: RMP*Comp Ver. 1.06 Results of Consequence Analysis Chemical: Ammonia (anhydrous) CAS #: 7664-41-7 Category: Toxic Gas Scenario: Worst-case Liquefied under pressure Quantity Released: 160936 pounds Release Duration: 10 min Release Rate: 16100 pounds per min Mitigation Measures: NONE Topography: Rural surroundings (terrain generally flat and unobstructed) Toxic Endpoint: 0.14 mg/L; basis: ERPG-2 Estimated Distance to Toxic Endpoint: 6.9 miles (11.1 kilometers) --------Assumptions About This Scenario--------- Wind Speed: 1.5 meters/second (3.4 miles/ hour) Stability Class: F Air Temperature: 77 degrees F (25 degrees C) ------------------------------------------------ AMPAC has also prepared two alternative scenarios based on accidents that are more plausible than the rupture of a rail car. EPA's RMP*Comp Ver. 1.06 was again used to calculate the results of the offsite alternate release consequence analysis. For the WECCO division operations (Ammonium Chloride production), the breakage of a one inch pipeline to the process was considered. AMPAC's ammonia tanks have excess flow valves that normally will close completely or very nearly completely in the event of a line breakage. In this case, a ninety per cent reduction in leakage was assumed. Bad weather was assumed to slow the response so that it took thirty minutes for employees to reach response gear, follow the plan, suit up and close the required valves to stop the leak. Chemical: Ammonia (anhydrous) CAS #: 7664-41-7 Category: Toxic Gas Scenario: Alternative Liquefied und er pressure Release Duration: 30 minutes Storage Parameters: Release from Pipe Initial Operational Flow Rate: 50 pounds per min Cross-sectional area of pipe: 0.719 square inches Operational pipe pressure: 180 psi Change in pipe elevation: 2 feet Release Rate: 243 pounds per min Mitigation Measures: Active Mitigation to Reduce Release Rate by factor of 0.9 Topography: Rural surroundings (terrain generally flat and unobstructed) Toxic Endpoint: 0.14 mg/L; basis: ERPG-2 Estimated Distance to Toxic Endpoint: 0.3 miles (0.5 kilometers) --------Assumptions About This Scenario--------- Wind Speed: 3 meters/second (6.7 miles/hour) Stability Class: D Air Temperature: 77 degrees F (25 degrees C) ------------------------------------------------ For the AMPAC American Azide Division process (Sodium Amide Production), a three inch line was assumed to break in the gas line leading to the process. The active mitigation ( excess flow valves) were assumed to seat within three minutes and stop the flow ending the release. RMP*Comp Ver. 1.06 Results of Consequence Analysis Chemical: Ammonia (anhydrous) CAS #: 7664-41-7 Category: Toxic Gas Scenario: Alternative Release Duration: 3 minutes Storage Parameters: Hole or puncture area: 7.39266 square inches Tank Pressure: 60 psi (actually pipeline pressure absolute) Tank Temp: 100 F Release Rate: 352 pounds per min Mitigation Measures: NONE Topography: Rural surroundings (terrain generally flat and unobstructed) Toxic Endpoint: 0.14 mg/L; basis: ERPG-2 Estimated Distance to Toxic Endpoint: 0.4 miles (0.6 kilometers) --------Assumptions About This Scenario--------- Wind Speed: 3 meters/second (6.7 miles/hour) Stability Class: D Air Temperature: 77 degrees F (25 degrees C) ------------------------------------------------ For flammable materials, the scenario requires that every bit of material in the container is released, vaporized, and using standard assumptions (default assumptions preselected by EPA) participate in a vapor cl oud explosion. A standard set of meteorological conditions is used, and a circle radius is calculated out to an EPA determined overpressure of 1 psi. EPA has provided a set of guidance tables to conduct offsite consequence analysis. The scenario required to be used was a vapor cloud explosion from the single largest container of propane on site. This container is a storage tank with 30,000-gallon capacity that is limited by written operating procedures to not filling beyond 26,000 gallons (86.667%). With this control, the tanks can contain 109356 pounds of propane. AMPAC operators visit these tanks each day to inspect them. It is very unlikely that a situation could occur and go undetected that could result in the worst case scenario RMP*Comp Ver. 1.06 was used to calculate the results of the scenario. Chemical: Propane CAS #: 74-98-6 Category: Flammable Gas Scenario: Worst-case Liquefied under pressure Quantity Released: 109356 pounds Release Type: Vapor Cloud Explosion Estimat ed Distance to 1 psi overpressure: .4 miles (.6 kilometers) --------Assumptions About This Scenario--------- Wind Speed: 1.5 meters/second (3.4 miles/hour) Stability Class: F Air Temperature: 77 degrees F (25 degrees C) ------------------------------------------------ The alternative scenario chosen was the breakage of a 2" pipeline flexible connection. . AMPAC's large process support propane tanks have excess flow valves that normally will close completely or very nearly completely in the event of a line breakage. The excess flow valves were assumed to cause a 90% reduction in the release. A vapor cloud fire was chosen as the hazard evaluated in the release. RMP*Comp Version 1.06 was used to calculate the results of the consequence analysis. Chemical: Propane CAS #: 74-98-6 Category: Flammable Gas Scenario: Alternative Liquefied under pressure Release Type: Vapor Cloud Fire Storage Parameters: Release from Pipe Initial Operational Flow Rate: 35 pounds per min Cross-sectional ar ea of pipe: 2.953 square inches Operational pipe pressure: 195 psi Change in pipe elevation: 3 feet Release Rate: 964 pounds per min Mitigation Measures: Active Mitigation to Reduce Release Rate by factor of 0.9 Topography: Rural surroundings (terrain generally flat and unobstructed) Lower Flammability Limit: 36 mg/L Estimated Distance to Lower Flammability Limit: <0.1 miles (<0.16 kilometers) 4. The general accidental release prevention program and chemical-specific prevention steps: AMPAC is regulated under OSHA's PSM standard for ammonia and EPA's regulations on risk management programs, which requires a 14 point program be present to prevent accidents. The quantity of Propane on site triggers exactly the same requirements for propane through the EPA Regulations on risk management plans although propane is not covered under OSHA's PSM standard when used to provide heat. AMPAC has a maintenance program that generates preventive maintenance work orders routinely through a compu ter program. AMPAC's operators and mechanics are well trained. AMPAC has written operating procedures which meet ISO 9001 requirements for a quality system and are audited by outside auditors on a regular schedule. These items all serve to minimize the risk of an accidental release. AMPAC has additionally trained its response team so that a well trained team is present 24 hours per day, 7 days a week to respond to any emergency in a timely and appropriate fashion. The emergency response program specifically covers ammonia and propane as well as other materials on site not regulated by EPA under the risk management program. 5. The five-year accident history AMPAC has had no releases of propane from the steam production process or ammonia from either of the ammonia using processes that threatened on site or off site personnel. No injuries have occurred from either material. No evacuations have occurred as a result of either material and no property damage has occurred as a resu lt of either ammonia or propane. AMPAC does have an incident investigation program. AMPAC does take corrective actions even for minor incidents that do not trigger recording under this program. AMPAC continues to develop its safety programs through both new technologies and learning from any experiences no matter how minor. 6. The emergency response program: As previously mentioned, AMPAC has a well-trained emergency response organization. AMPAC has written response procedures on which the team has been trained and the procedures are provided to the Iron County Local Emergency Planning Committee (LEPC) for coordination. The response team has periodic drills, which vary from responding to fires and evacuating on site personnel to responding to spills. AMPAC has trained local outside response personnel such as the fire department and high way patrol. AMPAC has served as the site for community drill involving a simulated acid spill in the past and will make itself available for any reasonable requests by the LEPC for future drills. AMPAC has had a clear history of immediately notifying outside responders in the past (these responses have involved items not regulated under the risk management regulations). AMPAC has worked side by side with outside responders to provide any information that they may require in preparing their responses to any AMPAC incident. 7. Planned changes to improve safety AMPAC will add new valves that can be more remotely controlled and that act to create a shutdown if excessive temperatures occur at the ammonia or propane tanks. The valves should be installed by August 31, 1999 and were identified during an April 1999 audit as candidates for improvement. Maintenance will occur to replace relief valves on the tanks on periodic schedules with an upcoming replacement scheduled to occur by August 31, 1999. |