Terra Nitrogen - Port Neal Plant - Executive Summary |
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I. Executive Summary Introduction The Terra Nitrogen - Port Neal Plant manufactures anhydrous ammonia and urea ammonium nitrate (UAN) solution. Intermediates in the manufacture of these products include nitric acid, urea solution, and ammonium nitrate solution. The regulated substances, as defined by 40 CFR Part 68 that exceed the threshold quantity are ammonia and hydrogen. It is Terra Nitrogen's policy to prevent accidental releases from the plant by effective process safety management (PSM) programs and procedures that include participation by plant employees in every element of the PSM program; regular analysis of process hazards utilizing current and accurate process safety information; maintaining current operating procedures; providing timely and comprehensive training for all employees involved in operating and maintaining process equipment; overseeing the activities of contractors and ensuring that they are trained to perform their jobs safely; following established pre- startup safety review and management of change procedures to ensure that modifications are adequately evaluated for safety; administering a comprehensive mechanical integrity program to ensure that process equipment is maintained in accordance with good engineering practice and accepted industry standards; investigating incidents when they do occur so that we can promptly correct deficiencies and learn from the experience; and auditing the PSM Program on a regular basis to verify that elements, procedures and systems are in place and adequate. It is our policy to maintain a current and accurate written emergency response plan and a well-trained and equipped onsite emergency response team; a system to notify neighbors in the event of a release; and to coordinate emergency response planning with local authorities and exercise those plans annually. Offsite Consequence Analysis The Port Neal Plant Toxic Worst Case Scenario involves ammonia and has offsite impact. The Alternative Releas e Scenario for ammonia ia a 2" pipe break, resulting in the release of 5,400 pounds over a ten minute period. The distance to the toxic endpoint for ammonia (200ppm) is estimated to be 0.35 miles. The effect of the alternative toxic release is limited by the operation of excess flow valves and emergency shutdown procedures in place at the facility. The Port Neal Plant Flammable Worst Case Scenario involves hydrogen and has offsite impact. The Alternative Release Scenario for hydrogen is a 1" pipe break resulting in a release of 540 pounds over a 10 minute period. The distance to the flamable endpoint (3.3% volume -LFL) is estimated to be 0.06 miles. The impact from the Alternative Flammable Release Scenario for hydrogen is limited by emergency shutdown procedures. Accidental Release Prevention Program The Port Neal plant has a comprehensive Process Safety Management (PSM) Program and is subject to the Occupational Safety and Health Administration's standard for process safety ma nagement of highly hazardous chemicals found at 29 CFR Part 1910.119. Key elements of the PSM program include: 1) stringent design standards of equipment which incorporate substantial safety factors and include state of the art monitoring and control instrumentation; 2) extensive process safety information that is accurate and up to date; 3) well-trained operating, maintenance, and contract personnel; 4) written operating and maintenance procedures; 5) mechanical integrity procedures for process equipment inspections and quality control; 6) management of change and pre-startup safety review procedures; 7) periodic, detailed evaluation of each process area by a team utilizing HazOp methodology; 8) regular audits of the PSM program; and 9) employee participation in every element of the PSM Program. Five Year Accident History An ammonium nitrate explosion occurred on December 13, 1994, which caused the release of approximately 4,000 tons of ammonia. The explosion resulted in four fat alities and numerous injuries onsite as well as significant on-site property damage, business interruption, and additional expense. Off-site impact from the accident was limited to temporary sheltering-in-place and evacuation of plant neighbors. Emergency Response Program The Port Neal plant also has a comprehensive Emergency Response Program which includes a written plan that is coordinated with local authorities, a 50-plus member emergency response team, and an emergency notification system that utilizes both in-plant sirens and the Community Alert Network telephone system. Plant personnel have participated in county-wide emergency drills with local responders including Woodbury County Disaster Services (LEPC), Salix Fire and Rescue, Sioux City Fire Department and Sioux City HazMat. Additionally the plant exercises its emergency response plan regularly with in-plant drills. |