El Paso Refinery (Chevron North) - Executive Summary
ACCIDENTAL RELEASE PREVENTION AND RESPONSE POLICIES |
The Chevron El Paso Refinery has a long-standing commitment to worker and public safety. This commitment is demonstrated by the resources invested in accident prevention, such as training personnel and considering safety in the design, installation, operation, and maintenance of our processes. Our policy is to implement reasonable controls to prevent foreseeable releases of regulated substances. However, if a release does occur, our trained personnel will respond to control and contain the release.
DESCRIPTION OF THE STATIONARY SOURCE AND REGULATED SUBSTANCES
The Chevron El Paso Refinery, located in El Paso, Texas, operates a variety of processes to produce petroleum products (e.g., fuel gas, propane, butane, gasoline, diesel, and jet fuel) from raw crude oil. The refinery has several regulated flammables, which include:
HAZARD ASSESSMENT RESULTS
The worst case scenario (WCS) associated with a release of flammable substances in a Program 3 process at the refinery is a Vapor Cloud Explosion (VCE) involving a Liquefied Petroleum Gas (LPG) Sphere containing butane. Based on equations in EPA's Offsite Consequence Analysis Guidance document, this scenario results in the predicted 1.0 psi blast overpressure going off-site.
The Alternative Release Scenario (ARS) for flammable substances at the refinery is a VCE resulting from the release of a flammable mixture from a vessel leak in the Light Ends Recovery (LER) Unit. This scenario results in the predicted 1.0 psi blast overpressure going off-site. The Baker-Strehlow method (reference Center for Chemical Process Safety) was used for this analysis.
FIVE-YEAR ACCIDENT HISTORY
The Chevron El Paso refinery has an excellent record of accident prevention over the past 5 years. There have not been any accidents in a covered pr
ocess involving a regulated substance over the past five years that meet the RMP criteria.
GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM STEPS
The following is a summary of the general accident prevention program in place at the Chevron El Paso refinery. Because processes at the refinery that are regulated by the EPA RMP regulation are also subject to the OSHA PSM standard, this summary addresses each of the OSHA PSM elements and describes the management system in place to implement the accident prevention program.
The Chevron El Paso refinery encourages employees to participate in all facets of process safety management and accident prevention. Examples of employee participation range from updating and compiling technical documents and chemical information to participating as a member of a process hazard analysis (PHA) team. Employees have access to all information created as part of the refinery accident prevention program. In addition, the refinery has
a number of initiatives underway that address process safety and employee safety issues. These initiatives include forming teams to promote both process and personal safety. The teams typically have members from various areas of the plant, including operations, maintenance, engineering, and plant management.
Process Safety Information
The Chevron El Paso refinery keeps a variety of technical documents that are used to help maintain safe operation of the processes. These documents address chemical properties and associated hazards, limits for key process parameters and specific chemical inventories, and equipment design basis/configuration information. Specific departments within the refinery are assigned responsibility for maintaining up-to-date process safety information.
Chemical-specific information, including exposure hazards and emergency response/ exposure treatment considerations, is provided in material safety data sheets (MSDSs). This information is supplemented by docu
ments that specifically address known corrosion concerns and any known hazards associated with the inadvertent mixing of chemicals. For specific process areas, the refinery has documented safety-related limits for specific process parameters (e.g., temperature, level, composition) in an Electronic Operating Manual for each process unit. The refinery ensures that the process is maintained within these limits using process controls and monitoring instruments, highly trained personnel, and protective instrument systems (e.g., automated shutdown systems). The refinery also maintains numerous technical documents that provide information about the design and construction of process equipment. This information includes materials of construction, design pressure and temperature ratings, electrical rating of equipment, etc. This information, in combination with written procedures and trained personnel, provides a basis for establishing inspection and maintenance activities, as well as for e
valuating proposed process and facility changes to ensure that safety features in the process are not compromised.
Process Hazard Analysis (PHA)
The Chevron El Paso refinery has a comprehensive program to help ensure that hazards associated with the various processes are identified and controlled. Within this program, each process is systematically examined to identify hazards and ensure that adequate controls are in place to manage these hazards.
The Chevron El Paso refinery primarily uses the hazard and operability (HAZOP) analysis technique to perform these evaluations. HAZOP analysis is recognized as one of the most systematic and thorough hazard evaluation techniques. The analyses are conducted using a team of people who have operating and maintenance experience as well as engineering expertise. This team identifies and evaluates hazards of the process as well as accident prevention and mitigation measures, and makes suggestions for additional prevention and/or mitigation me
asures when the team believes such measures are necessary.
The PHA team findings are forwarded to process area teams for consideration and priority resolution. Implementation of mitigation options in response to PHA findings is based on a relative risk ranking assigned by the PHA team. This ranking helps ensure that potential accident scenarios assigned the highest risk receive attention first. All approved mitigation options being implemented in response to PHA team findings are tracked until they are complete. The final resolution of each finding is documented and retained.
To help ensure that the process controls and/or process hazards do not eventually deviate significantly from the original design safety features, the Chevron El Paso refinery periodically updates and revalidates the hazard analysis results. These periodic reviews are conducted at least every 5 years and will be conducted at this frequency until the process is no longer operating. The results and findings fr
om these updates are documented and retained. Once again, the team findings are forwarded to process area teams for consideration and priority resolution.
The Chevron El Paso refinery maintains written procedures that address various modes of process operations, such as (1) unit startup, (2) normal operations, (3) temporary operations, (4) emergency shutdown, (5) normal shutdown, and (6) initial startup of a new process. These procedures can be used as a reference by experienced operators and provide a basis for consistent training of new operators. These procedures are periodically reviewed and certified as current and accurate. The procedures are maintained current and accurate by revising them as necessary to reflect changes made through the Management of Change (MOC) process.
To complement the written procedures for process operations, the Chevron El Paso refinery has implemented a comprehensive training program for all employees involved in
operating a process. New employees receive basic training in refinery operations if they are not already familiar with such operations. After successfully completing this training, a new operator is paired with a senior operator to learn process-specific duties and tasks. After operators demonstrate (e.g., through tests, skills demonstration) having adequate knowledge to perform the duties and tasks in a safe manner on their own, they can work independently. In addition, all operators periodically receive refresher training on the operating procedures to ensure that their skills and knowledge are maintained at an acceptable level. All of this training is documented for each operator, including the means used to verify that the operator understood the training.
The Chevron El Paso refinery uses contractors to supplement its workforce during periods of increased maintenance or construction activities. Because some contractors work on or near process equipment, the refi
nery has procedures in place to ensure that contractors (1) perform their work in a safe manner, (2) have the appropriate knowledge and skills, (3) are aware of the hazards in their workplace, (4) understand what they should do in the event of an emergency, (5) understand and follow site safety rules, and (6) inform refinery personnel of any hazards that they find during their work. This is accomplished by providing contractors with (1) a process overview, (2) information about safety and health hazards, (3) emergency response plan requirements, and (4) safe work practices prior to their beginning work. In addition, the Chevron El Paso refinery evaluates contractor safety programs and performance during the selection of a contractor. Refinery personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations.
Pre-startup Safety Reviews (PSSRs)
The Chevron El Paso refinery conducts a PSSR for any new facility or facility modifica
tion that requires a change in the process safety information. The purpose of the PSSR is to ensure that safety features, procedures, personnel, and the equipment are appropriately prepared for startup prior to placing the equipment into service. This review provides one additional check to make sure construction is in accordance with the design specifications and that all supporting systems are operationally ready. The PSSR review team uses checklists to verify all aspects of readiness. A PSSR involves field verification of the construction and serves a quality assurance function by requiring verification that accident prevention program requirements are properly implemented.
A key aspect of Chevron's mechanical integrity program involves the sound design of process equipment based on safety-in-design standards that meet or exceed industry standards. The Chevron El Paso refinery also has well-established practices and procedures to maintain pressure vessels
, piping systems, relief and vent systems, controls, pumps and compressors, and emergency shutdown systems in a safe operating condition. The basic aspects of this program include: (1) conducting training, (2) developing written procedures, (3) performing inspections and tests, (4) correcting identified deficiencies, and (5) applying quality assurance measures. In combination, these activities form a system that maintains the mechanical integrity of the process equipment.
Maintenance personnel receive training on (1) an overview of the process, (2) safety and health hazards, (3) applicable maintenance procedures, (4) emergency response plans, and (5) applicable safe work practices to help ensure that they can perform their job in a safe manner. Written procedures help ensure that work is performed in a consistent manner and provide a basis for training. Inspections and tests are performed to help ensure that equipment functions as intended, and to verify that equipment is within a
cceptable limits (e.g., adequate wall thickness for pressure vessels). If a deficiency is identified, employees will correct the deficiency before placing the equipment back into service (if possible), or an MOC team will review the use of the equipment and determine what actions are necessary to ensure the safe operation of the equipment.
Another integral part of the mechanical integrity program is quality assurance. The Chevron El Paso refinery incorporates quality assurance measures into equipment purchases and repairs. This helps ensure that new equipment is suitable for its intended use and that proper materials and spare parts are used when repairs are made. The refinery also has an established Positive Material Identification (PMI) Program in place to verify alloy materials prior to installation.
Safe Work Practices
The Chevron El Paso refinery has long-standing safe work practices in place to help ensure worker and process safety. Examples of these include (1) control
of the entry/presence/exit of support personnel, (2) a lockout/tagout procedure to ensure isolation of energy sources for equipment undergoing maintenance, (3) a procedure for safe removal of hazardous materials before process piping or equipment is opened, (4) a permit and procedure to control spark-producing activities (i.e., hot work), and (5) a permit and procedure to ensure that adequate precautions are in place before entry into a confined space. These procedures (and others), along with training of affected personnel, form a system to help ensure that operations and maintenance activities are performed safely.
Management of Change
The Chevron El Paso refinery has a comprehensive system to manage change. This system requires that changes to items such as process equipment, chemicals, technology (including process-operating conditions), procedures, and other facility changes be properly reviewed and authorized before being implemented. Changes are reviewed to (1) ensure that
adequate controls are in place to manage any new hazards and (2) verify that existing controls have not been compromised by the change. Affected chemical hazard information, process operating limits, and equipment information, as well as procedures, are updated to incorporate these changes. In addition, operating and maintenance personnel are provided any necessary training on the change.
The Chevron El Paso refinery promptly investigates all incidents that resulted in, or reasonably could have resulted in, a fire/explosion, toxic gas release, property damage, environmental loss, or personal injury. The goal of each investigation is to determine the facts and develop corrective actions to prevent a recurrence of the incident or a similar incident. The investigation team documents its findings and develops recommendations to prevent a recurrence. Corrective actions taken in response to the investigation team's findings and recommendations are tracked until
they are complete. The final resolution of each finding or recommendation is documented, and the investigation results are reviewed with all employees (including contractors) who could be affected by the findings. Incident investigation reports are retained for at least 5 years so that the reports can be reviewed during future PHAs and PHA revalidations.
To help ensure that the accident prevention program is functioning properly, the Chevron El Paso refinery periodically conducts an audit to determine whether the procedures and practices required by the accident prevention program are being implemented. Compliance audits are conducted at least every 3 years. Both hourly and management personnel participate as audit team members. The audit team develops findings and sets priorities for resolution. Corrective actions taken in response to the audit team's findings are tracked until they are complete. The final resolution of each finding is documented, and the t
wo most recent audit reports are retained.
CHEMICAL SPECIFIC PREVENTION STEPS
The processes at the Chevron El Paso refinery have hazards that must be managed to ensure continued safe operation. The accident prevention program summarized previously is applied to all Program 3 EPA RMP-covered processes at the Chevron El Paso refinery. Collectively, these prevention program activities help prevent potential accident scenarios that could be caused by (1) equipment failures and (2) human errors.
In addition to the accident prevention program activities, the Chevron El Paso refinery has safety features on many units to help (1) contain/control a release, (2) quickly detect a release, and (3) reduce the consequences of (mitigate) a release. The following types of safety features are used in various processes:
1. Process relief valves that discharge to a flare to capture and incinerate episodic releases
2. Valves to permit isolation of the process (manual
3. Automated shutdown systems for specific process parameters (e.g., high level, high temperature)
4. Curbing or diking to contain liquid releases
5. Redundant equipment and instrumentation (e.g., uninterruptible power supply for process control system, backup power, backup pumps)
6. Atmospheric relief devices
7. High vibration monitoring equipment and shutdown systems
1. Fire extinguishing system
2. Trained emergency response personnel
3. Personal protective equipment (e.g., protective clothing, self-contained breathing
EMERGENCY RESPONSE PROGRAM INFORMATION
The Chevron El Paso refinery maintains a written emergency response program, which is in place to protect worker and public safety as well as the environment. The program consists of procedures for responding to a release of a regulated substance, including the possibility of a fire or explosion if a flammable substance is accidentally released. The procedures addres
s all aspects of emergency response, including proper first-aid and medical treatment for exposures, evacuation plans and accounting for personnel after an evacuation, notification of local emergency response agencies if a release occurs, and post-incident cleanup and decontamination requirements. In addition, the Chevron El Paso refinery has procedures that address maintenance, inspection, and testing of emergency response equipment, as well as instructions that address the use of emergency response equipment. Employees receive training in these procedures as necessary to perform their specific emergency response duties. The emergency response program is updated when necessary based on modifications made to refinery processes or other refinery facilities. The emergency response program changes are administered through the MOC process, which includes informing and/or training affected personnel in the changes.
The overall emergency response program for the Chevron El Paso refinery i
s coordinated with the El Paso Fire Department and the Local Emergency Planning Committee (LEPC). This coordination includes periodic meetings of the committee, which includes local emergency response officials, local government officials, and industry representatives. The Chevron El Paso refinery has direct lines of phone communication with the fire department to facilitate emergency notifications and response support if needed. In addition to periodic LEPC meetings, the Chevron El Paso refinery conducts periodic "hands-on" emergency drills on-site that involve the LEPC and emergency response organizations, and the refinery provides annual refresher training to local emergency responders regarding the hazards of regulated substances in the refinery.
PLANNED CHANGES TO IMPROVE SAFETY
At the Chevron El Paso refinery, safety improvements are routinely evaluated and implemented, as needed, as part of our general health and safety best management practices and the various general acc
idental release prevention programs in place. As required under the RMP, and other similar or related programs under OSHA, we routinely and systematically use appropriate hazard assessment techniques to identify hazards that may result in accidental releases, design and maintain a safe facility, taking such steps as are necessary to prevent releases, and are prepared to respond to accidental releases if they do occur.