Praxair - Wilmington, CA - Executive Summary

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The Praxair facility at Wilmington, California is an air separation plant.  We take air from the atmosphere and break it down into its pure components, which are mainly oxygen, nitrogen and argon.  The plant uses a simple process of drying and distillation to separate and liquefy these components.  The final cryogenic liquid products are stored in our insulated storage tanks, and shipped by truck to customers throughout the west.  Our products are also delivered by pipeline to local refineries and chemical plants. 
In addition to the air separation process, the Wilmington facility operates a cogeneration plant that produces electricity as a byproduct.  This cogen plant emits air pollutants that must be treated before they can be discharged into the atmosphere.  The plant has an Emission Control Module that uses anhydrous ammonia to convert the air pollutants into harmless substances such as nitrogen and water vapor.  Anhydrous ammonia is listed as a regulated toxic substance in EPA's R 
isk Management Program rule, with a threshold quantity of 10,000 pounds.  The emission control unit at the Wilmington plant contains about 48,000 pounds of ammonia, and is therefore subject to the RMP rule.  None of our primary products (oxygen, nitrogen and argon) are regulated by the RMP rule. 
Under the RMP rule, Praxair is required to report a Worst Case Scenario for the Wilmington plant, which is defined by the EPA as the release of the entire contents of the largest ammonia vessel in our process, with essentially none of the safety systems and devices that are in place to prevent such an occurrence functioning as designed.  The release is assumed to occur over a 10 minute time period, and under the most stable atmospheric and weather conditions, which minimizes the dispersion and dilution of the release and presents the absolute worst case that could possibly occur.  Given all of these conditions, we are then required to estimate the distance to an EPA-specified toxic endpoint, w 
hich is defined to be a concentration of 200 ppm for ammonia.  At the Wilmington facility, the largest ammonia vessel contains about 48,000 pounds.  Using the criteria listed above, the Worst Case Scenario would result in a maximum downwind distance of about 2.5 miles to the EPA-specified endpoint.  To determine this distance, we used the EPA's "Risk Management Program Guidance for Ammonia Refrigeration." 
We are also required to report an Alternative Release Scenario, or planning scenario, under the RMP rule.  While an Alternative Release may never occur at a facility, it is generally accepted to be more likely, or more credible, than the Worst Case Scenario, and can be used by the facility and local response organizations to plan community emergency response activities.  The RMP rule assumes more typical atmospheric and weather conditions for an Alternative Release Scenario, and allows a facility to take credit for safety devices and other mitigation systems that are in place to mini 
mize the likelihood and effects of a release.  When selecting an ARS, EPA suggests a facility consider scenarios such as transfer hose releases, valve and flange leaks, pump seal leaks, and shipping container mishaps, among others.  For the emission control process, all of these scenarios would be equivalent to a release from a small hole (1/4" diameter) in a tank or pipe containing ammonia at the highest system pressure.  At the Wilmington facility, a release of this type would result in a maximum downwind distance of about 0.1 miles, or 530 feet.  To determine this distance, we used the EPA's "Risk Management Program Guidance for Ammonia Refrigeration." 
In accordance with OSHA's Process Safety Management standard and EPA's Risk Management Program rule, the Wilmington facility has a comprehensive accident prevention program in place to ensure the safety of our employees, our neighbors and the community around us.  On a local level, this prevention program is built around process safe 
ty concepts such as: 
7 Documented process safety information to ensure the process design is understood and maintained throughout its life; 
7 Process hazard analysis to identify and control all of the hazards associated with handling anhydrous ammonia; 
7 Trained operators, using written operating procedures, to safely operate the process as intended; and 
7 Maintenance programs and procedures to ensure the on-going mechanical integrity of the process. 
The prevention program is audited periodically, by our corporate assessment group, to ensure that the process safety concepts and practices are in place and working effectively. 
As a result of our process safety and risk management practices, the Wilmington facility has not had an accident involving ammonia in the last five years.  In the event of an emergency, the facility has an emergency action plan in place, which contains procedures for employees to follow, including notification of local response agencies.  All facility employees  
are trained in their role in the emergency action plan, and Praxair policy requires that emergency drills be conducted at least annually. 
Praxair is committed to continuous improvement of its safety and environmental programs.  Recent enhancements of our safety, health and environmental programs include upgrading our underground fuel storage tanks to minimize the possibility of an accidental release.  The Wilmington facility has also recently begun a lead paint removal initiative to eliminate this potential health hazard in our workplace and community. 
Praxair is a producer and distributor of industrial gases with almost 100 years of experience.  We are committed to being the best performing industrial gas company in all aspects of our business, including safety, health and environmental affairs.  Praxair is a member the Chemical Manufacturers Association's Responsible Care initiative, which is intended to ensure the safe operation of chemical facilities and enhance the relationships 
between the chemical industry and the communities in which we operate.  Internally, we use a combination of extensive engineering standards and design safety work processes, coupled with operational and personnel safety programs, to ensure the safe operation of all of our facilities.  Our company-wide goal of "Zero/Zero" (which means zero accidents and zero injuries or illnesses at every location) reflects the dedication and commitment to safety throughout the entire Praxair organization.
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