Terra Nitrogen Limited Partnership,Verdigris Plant - Executive Summary

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The Terra Nitrogen Verdigris plant (Verdigris plant) manufactures anhydrous ammonia and urea ammonium nitrate (UAN) solution and the by-products liquified carbon dioxide and argon.  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, which are present at the facility in more than a threshold quantity are ammonia, chlorine, and  hydrogen. 
It is Terra Nitrogen's policy to prevent accidental releases from the Verdigris plant by effective process safety management programs and procedures that include: participation by all plant employees in every element of PSM; regular analysis of process hazards utilizing current and accurate process safety information; maintaining current and accurate written 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 job 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 to promptly correct deficiencies and learn from the experience; and audit the entire PSM program on a regular basis to verify that elements, procedures, and systems are in place and adequate.  In addition, it is the Verdigris plant's policy to maintain a current and accurate written emergency response plan, a well trained and equipped onsite  emergency response team, a system to notify facility 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 Verdigris Plant Toxic Worst Case Scenario involves ammonia and has offsite impact.  The Alternative Release Scenario for ammonia is 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 (200 ppm) is estimated to be 0.35 miles.  The Alternative Release Scenario for chlorine is a 3/8" pipe break resulting in a release of 1,560 pounds over a 120 minute period.  The distance to the toxic endpoint for chlorine (3 ppm) is estimated to be 0.51 miles.  The effect of the alternative toxic releases is limited by the operation of excess flow valves and emergency shutdown procedures in place at the facility. 
The Verdigris Plant Flammable Worst Case Scenario 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 flammable endpoint (3.3% by volume LF 
L) is estimated to be 0.06 miles.  The effect of the Alternative Release Scenario for hydrogen is limited by emergency shutdown procedures. 
Accidental Release Prevention Program 
The Verdigris plant has a comprehensive Process Safety Management (PSM) Program and is subject to the Occupational Safety and Health Administration's standard for process safety management 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 contractor personnel; 4) written operating, maintenance, and safe work procedures; 5) mechanical integrity procedures for process equipment inspections and quality control; 6)  management of change and pre-startup review procedures; 7)  periodic, detaile 
d evaluation of each process area by a team utilizing HAZOP methodology; 8)  regular PSM program audits; and 9) employee participation in every element of the PSM program. 
Five-Year Accident History 
There have been no accidental releases from covered processes at the Verdigris plant within the past five years that resulted in deaths, injuries, or significant property damage on site, or known offsite deaths, injuries, evacuations, sheltering in place, property damage or environmental damage. 
Emergency Response Program 
The Verdigris plant also has a comprehensive Emergency Response Program which includes a written plan that is coordinated with local authorities, a 55-plus member emergency response team, and an emergency notification system that utilizes both in-plant sirens and the Community Alert Network telephone system.  Verdigris plant personnel are active members of the Rogers County Local Emergency Planning Committee (LEPC).  The plant exercises it's emergency response plan annua 
lly and also participates in county-wide drills that are staged by the LEPC and other local emergency response authorities.
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