Navajo Refining Company - Executive Summary
General Executive Summary for Chemical, Manufacturing and Oil Refining Facilities |
1. Accidental Release Prevention and Emergency Response Policies
We at Navajo Refining Company are strongly committed to employee, public and environmental safety. This commitment is demonstrated by our comprehensive accidental release prevention program that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at our facility. It is our policy to implement appropriate controls to prevent possible releases of regulated substances.
2. The Stationary Source and the Regulated Substances Handled
Our facility's primary activities encompass Petroleum refining. We have 3 regulated substances present at our facility. These substances are Butane (including isobutane), Propane and Hydrogen fluoride/Hydrofluoric acid [Hydrofluoric acid]. Butane is used for Alkylation Unit feed and gasoline blend stock. Propane is used for Alkylatio
n Unit feed and LPG product. Hydrogen fluoride/Hydrofluoric acid [Hydrofluoric acid] is used to promote the alkylation reaction.
The maximum inventory of Butane at our facility is 6,846,042 lb. while Propane and Hydrogen fluoride/Hydrofluoric acid [Hydrofluoric acid] are present at our facility in quantities of 716,513 lb. and 115,600 lb. respectively.
3. The Worst Case Release Scenario(s) and the Alternative Release Scenario(s), including administrative controls and mitigation measures to limit the potentially impacted distances for each reported scenario.
To perform the required offsite consequence analysis for our facility, we have used the EPA's OCA Guidance Reference Tables or Equations. This was selected as the basis for the calculations since it generally predicts distances on the high side as compared to more sophisticated models. Scenarios evaluated included both chemical-specific releases and releases of mixtures. The following paragraphs provide details of the chosen s
The worst case release scenario submitted for Program 2 and 3 toxic substances as a class involves a catastrophic release from HF Alkylation. In this scenario 13900 lb. of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid] is released. The toxic liquid released is assumed to form a 1 cm deep pool from which evaporation takes place. The entire pool is estimated to evaporate over 10 minutes. Under worst-case weather conditions (Class F atmospheric stability and 1.5 m/s windspeed), the maximum distance corresponding to a toxic endpoint of 0.016 mg/L has been calculated as 11 miles. Note that this endpoint is well below the NIOSH threshold of 30 ppm established as immediately dangerous to life and health. The endpoint used tends to expand the potential "impact" area. Further contributing to increasing the impact radius is the fact that the protective mitigation measures set in place by Navajo are not considered because the regulatory program, by
definition, excludes active mitigation from the worst case scenario.
The alternative release scenario for Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid] involves a release from the HF Alkylation process. The scenario involves the release of 13900 lb. of HF. Toxic liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes place. The entire pool is estimated to have evaporated after 10 minutes. The release is also assumed to be controlled by a water deluge system. This active mitigation system has the effect of reducing the release by approximately 90%. Under neutral weather conditions (Class D stability, 3 m/s windspeed), the maximum distance to the toxic endpoint of 0.016 mg/L (extremely low compared to OSHA limits) of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid] has been calculated as 0.99 miles.
The worst case release scenario submitted for Program 2 and 3 flammable substances as a cl
ass involves a catastrophic release from Butane Bulk Storage. In this scenario 1,983,744 lb. of Butane is released. It is assumed that the entire quantity is released as a vapor, which finds an ignition source, with 10 percent of the released quantity participating in a vapor cloud explosion. Under worst case weather conditions, the calculated distance of 1.01 miles is obtained corresponding to an endpoint of 1 psi overpressure.
The alternative release scenario submitted for Program 2 and 3 flammable substances involves a release from Butane Bulk Storage. The release is assumed to result in a Vapor Cloud Fire. The scenario involves the release of 18,000 lb. of Butane in 3 minutes. Under neutral weather conditions, the maximum distance to the flammable endpoint of Lower flammability limit is 0.10 miles.
4. The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps
Our facility has taken all the necessary steps to comply with the accidental r
elease prevention requirements set out under 40 CFR part 68 of the EPA. The refinery has an active program in place to maintain compliance with the OSHA Process Safety Management (PSM) program. The following sections briefly describe the elements of the release prevention program that is in place at our stationary source.
Process Safety Information
Navajo Refining Company maintains a detailed record of safety information that describes the chemical hazards, operating parameters and equipment designs associated with all processes.
Process Hazard Analysis
Our facility conducts comprehensive studies to ensure that hazards associated with our processes are identified and controlled efficiently. The methodology used to carry out these analyses is What If or HAZOP. The studies are undertaken by a team of qualified personnel with expertise in engineering and process operations and are revalidated at a regular interval of every five years. Any findings related to the hazard analysis are
addressed in a timely manner. The most recent PHA/update was performed on 06/30/1998.
For the purposes of safely conducting activities within our covered processes, Navajo Refining Company maintains written operating procedures. These procedures address various modes of operation such as initial startup, normal operations, temporary operations, emergency shutdown, emergency operations, normal shutdown and startup after a turnaround. The information is regularly reviewed and is readily accessible to operators involved in the processes.
Navajo Refining Company has a comprehensive training program in place to ensure that employees who are operating processes are competent in the operating procedures associated with these processes. Refresher training is provided at least every three years and more frequently as needed.
Navajo Refining Company carries out highly documented maintenance checks on process equipment to ensure proper ope
rations. Process equipment examined by these checks includes among others, pressure vessels, storage tanks, piping systems, relief and vent systems, emergency shutdown systems, controls and pumps. Maintenance operations are carried out by qualified personnel with previous training in maintenance practices. Furthermore, these personnel are offered specialized training as needed. Any equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner.
Management of Change
Written procedures are in place at Navajo Refining Company to manage changes in process chemicals, technology, equipment and procedures. The most recent review/revision of management of change procedures was performed on 3/6/1995. Process operators, maintenance personnel or any other employee whose job tasks are affected by a modification in process conditions are promptly made aware of and offered training to deal with the modification.
Pre-start up safety r
eviews related to new processes and to modifications in established processes are conducted as a regular practice at Navajo Refining Company. The most recent review was performed on 03/14/1999. These reviews are conducted to confirm that construction, equipment, operating and maintenance procedures are suitable for safe startup prior to placing equipment into operation.
Navajo Refining Company conducts audits on a regular basis to determine whether the provisions set out under the RMP rule are being implemented. The most recent comliance audit was conducted on 12/8/97. These audits are carried out at least every 3 years and any corrective actions required as a result of the audits are undertaken in a safe and prompt manner.
Navajo Refining Company promptly investigates any incident that has resulted in, or could reasonably result in a catastrophic release of a regulated substance. These investigations are undertaken to identify the situat
ion leading to the incident as well as any corrective actions to prevent the release from reoccurring. All reports are retained for a minimum of 5 years.
Navajo Refining Company truly believes that process safety management and accident prevention is a team effort. Company employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements. In addition, our employees have access to all information created as part of the facility's implementation of the RMP rule, including information resulting from process hazard analyses in particular.
Our company hires contractors to conduct specialized maintenance and construction activities. Prior to selecting a contractor, a thorough evaluation of safety performance of the contractor is carried out. Navajo Refining Company has a strict policy of informing the contractors of known potential hazards related the contractor's work and the processes. Con
tractors are also informed of all the procedures for emergency response should an accidental release of a regulated substance occur.
5. Five-year Accident History
Navajo Refining Company has had an excellent record of preventing accidental releases over the last 5 years. Due to our stringent release prevention policies, the number of accidental releases has been reduced to a minimum.
There have been 8 accidental releases of regulated substances from our facility within the last 5 years. The first release took place on 02/27/1995 and involved 0.25 lb. of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid]. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
Another release, of 1 lb. of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid], occurred on 03/07/1995. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injurie
Another release, of 1 lb. of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid], occurred on 03/30/1995. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
Another release, of 1 lb. of Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid], occurred on 05/22/1995. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
Another release, of 10 lb. of Butane, occurred on 02/10/1996. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
Another release, of 15,000 lb. of Butane, occurred on 01/29/1997. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
Another release, of 25,000 lb. of Butane, occurred on 01/08/1998. No deaths or injuries occured offsite as a result of this accident. Onsite
, there were no deaths or injuries.
Another release, of 10 lb. of Propane, occurred on 04/09/1999. No deaths or injuries occured offsite as a result of this accident. Onsite, there were no deaths or injuries.
6. Emergency Response Plan
Navajo Refining Company has a written emergency response plan to deal with accidental releases of hazardous materials. The plan includes all aspects of emergency response including adequate first aid and medical treatment, evacuations, notification of local emergency response agencies and the public, as well as post-incident decontamination of affected areas.
To ensure proper functioning, our emergency response equipment is regularly inspected and serviced. In addition, the plan is promptly updated to reflect any pertinent changes taking place within our processes that would require a modified emergency response.
Eddy County LEPC is the Local Emergency Planning Committee (LEPC) with which our emergency plan has been coordinated and verified.
7. Planned Changes to Improve Safety
Navajo plans to continue improving and enhancing our already effective safety program. This established successful system is already in place to prevent and respond to accidental releases. Therefore, it is not surprising that no new courses of action have been identified by the Risk Management Plan. However, the ongoing process whereby Navajo reviews and evaluates new information will continue to result in ever improving refinements to our existing Safety Program.