Tosco San Francisco Area Refinery at Avon - Executive Summary

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The management and employees of San Francisco Area Refinery at Avon are fully committed to a program of responsible management in all areas including health, environment and safety.  In fulfilling this commitment, management will ensure systems are in place to provide the resources and training to identify issues and maintain a safe and healthful environment as indicated by Company standards, accepted safety and environmental practices, and compliance with legislative requirements.  We will operate and maintain our plants, facilities and equipment and handle our raw materials and products in a manner to prevent personal injuries/illnesses, losses to Company property, releases to the environment, or impact to the communities in which we operate. 
The Tosco San Francisco Area Refinery at Avon, located in Martinez, California, processes crude oil into useable petroleum products for  
our customers.  The refinery produces gasoline, automotive diesel, propane, butane, fuel oil and petroleum coke.  In order to produce these products, we store and handle large quantities of flammable materials.  
Crude oils contain varying amounts of sulfur and nitrogen impurities.  If these compounds are not removed in the refining process, they produce air pollutants when consumers burn the fuel products.  Many of the processes at the Avon refinery are used to remove these sulfur and nitrogen impurities. 
Sulfur impurities are removed and converted to elemental sulfur, sulfuric acid, and oleum (fuming sulfuric acid).  Elemental sulfur is sold for use in the manufacture of fertilizers and other industrial uses.  Sulfuric acid is used internally by the refinery as a catalyst.  Oleum is an industrial chemical that we transfer to an adjacent chemical plant for use in catalyst manufacture.  Our sulfur processing facilities produce intermediate products called hydrogen sulfide and sulfur d 
ioxide.  Oleum, hydrogen sulfide, and sulfur dioxide are regulated toxic substances.  However, the Avon Refinery is required to report only for oleum, because we do not store hydrogen sulfide or sulfur dioxide in amounts exceeding the threshold quantities for these chemicals. 
Nitrogen impurities are removed and converted to ammonia, which is a regulated toxic substance.  The ammonia that we produce is mainly sold for use in the manufacture of fertilizers.   
The EPA requires facilities to report on potential worst-case scenarios involving the regulated substances that we handle in amounts exceeding the threshold quantities.  The EPA mandates the release conditions for worst-case scenarios.  As a result, these scenarios ignore prevention programs that are designed to limit the number and size of chemical releases from our facility.  A toxic worst-case scenario describes the potential impacts if the vessel containing the largest quantity of the substance were  
to be damaged such that it released its entire contents within ten minutes without accounting for response measures that we would take to minimize the impact of such a release.  A flammable worst-case scenario describes the potential impacts if the vessel containing the largest quantity of the substance were to suddenly disappear, the contents were to instantaneously vaporize, and a resulting vapor cloud were to ignite and explode. 
An Alternate Release Scenario (ARS) represents a more likely event.  It is used to determine a reasonable outer bound for potential impacts in order to coordinate with local emergency responders.  Unlike the worst-case scenarios, our alternate release scenarios are based on actual equipment configurations.  In selecting our alternate release scenarios, we considered our practices and procedures for preventing and minimizing the size of chemical releases. 
The toxic worst-case scenario for the Avon refinery is based on releasing the entire contents of our la 
rgest ammonia storage tank.  Ammonia is a gas at room temperature.  To keep it in liquid form for storage, we pressurize and condense the gas.  We then store it in vessels designed for this purpose.  The results of the worst-case scenario indicate that releasing the entire contents of one of these vessels over a ten-minute period would result in significant offsite impact.  The ammonia toxic endpoint specified by EPA is 200 ppm (parts per million). 
The alternate release scenario for ammonia is the complete failure of a 1-inch loading hose during ammonia transfer operations.  The ammonia release rate that would result from such a failure is much smaller than the rate specified by the EPA for the worst-case scenario -- about 2%.  The results of the alternate release scenario for ammonia indicate that such a release would have an offsite impact. 
The flammable worst-case scenario for the Avon Refinery is based on releasing the entire contents of our largest butane storage vessel.  Butane 
is the material that is used in disposable lighters.  Like ammonia, butane is a gas at room temperature and the liquid form must be stored under pressure in vessels designed for this purpose.  The results of the worst-case scenario indicate that the instantaneous release and subsequent explosion of the entire contents of the vessel would result in offsite impact.  The endpoint specified by EPA for this type of release is an overpressure of 1 psi (pound per square inch). 
The alternate release scenario for flammable materials is a pool fire that results from spilling and igniting the contents of a large refrigerated butane storage tank.  The resulting fire would give off intense heat.  Because of the location of the storage tank, the heat given off by the fire could reach beyond our fenceline to adjacent unpopulated land.  The toxic endpoint specified by EPA for this type of release is a radiant heat intensity of 5 kilowatts per square meter for a duration of 40 seconds.  This heat int 
ensity is sufficient to cause second-degree burns (blistering) of bare skin. 
Tosco also selected an alternate release scenario for oleum.  This scenario represents a release from the oleum manufacturing process.  This results in the release of sulfur trioxide, which is the regulated substance contained in oleum.  The results of the alternate case scenario for oleum indicate that such a release could reach beyond our fenceline to adjacent unpopulated land.  The oleum toxic endpoint specified by EPA is 3.1 ppm. 
The Avon Refinery has experienced four accidental releases since June 1994 that qualify for reporting under the EPA's criteria . 
The first event occurred on December 6, 1994.  This event involved release of regulated flammables that resulted in a fire.  There were no personnel injuries or known off-site impacts other than the visible smoke and flames resulting from the fire.  Investigation of the event revealed that a pipe in a process heater rupture 
d due to localized overheating.  The rupture released a mixture of hydrogen and hydrocarbons that immediately ignited.  The overheating was traced to a combination of blocked process flow through the pipe and uneven heat distribution that occurred during the heater startup.  As a result of the investigation, operating and maintenance procedures were modified to ensure process flow and provide even heat distribution during heater startup. 
The second event occurred on January 21, 1997.  This event involved release of regulated flammables that resulted in an explosion and fire.  One Tosco employee was killed in the fire, and several other Tosco employees and contractors were injured as a result of the incident.  Off-site impacts were limited to the fire's visible smoke and flames.  Investigation of the event revealed that the outlet piping at a reactor ruptured due to high temperature caused by an uncontrolled reaction.  The rupture released a mixture of hydrogen and hydrocarbons that ig 
nited.  As a result of this incident, process controls were modified to automatically activate the emergency shutdown system in the event of excessive temperatures. 
The third event occurred on August 6, 1997.  This event involved a release of a small amount of oleum that sprayed onto a Tosco employee.  As result, the employee received some second-degree burns that required medical attention.  Investigation of the event revealed a faulty gasket at a flanged pipe joint which was subsequently repaired. 
The fourth event occurred on February 23, 1999.  This event involved a release of regulated flammables that resulted in a fire.  Although the fire was confined to limited area, one Tosco employee and three contractors were killed in the fire.  A second Tosco employee was seriously injured.  Investigation of the event revealed that a section of piping was removed without being properly isolated from the flammable materials contained in the process.  The flammable material was released and  
ignited by adjacent hot equipment.  As a result of this tragic accident, the Avon Refinery was shut down for a two-month period for re-training of refinery employees. 
The following summaries represent numerous prevention programs and practices at the Avon Refinery.  Avon Refinery employees are committed to operating a safe facility through the establishment, review, and continuous improvement of these programs and practices.   
The Avon Refinery encourages employees to participate in all aspects of process safety management and accident prevention.  Examples of employee participation include safety committee involvement, developing and reviewing safe operating procedures, and participation in the process hazard analysis program.   Information on the refinery's prevention programs is available to employees, and they are encouraged to recommend improvements to any of the programs.  In addition, refinery managem 
ent has a strong commitment to developing and enforcing written policies and procedures and encourages employee input to identify when a policy or procedure needs to be changed or improved to cover new tasks, revised regulations, or employee experience.  
The Avon Refinery maintains an extensive library of Process Safety Information.  Included is information related to chemicals in the process, the technology of the process, and the equipment in the process.  These documents include detailed information on chemical properties and their associated hazards, limits for key process parameters, and equipment design and configuration.  This information is available to all employees.  
Chemical specific information, including hazards, protective measures, symptoms, and first aid procedures is provided via Material Safety Data Sheets.  This information is available in hard copy format and via the refinery computer network. 
The limits for key process parameters (e.g 
. temperature, pressure, flow, and level) are documented in the unit operating manuals.  The process is maintained within these limits using computer process controls and monitoring instruments, highly trained personnel, and protective instrument systems (e.g. automated shutdown systems). 
Information on the design and construction of process equipment 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 the basis for establishing inspection and maintenance activities, as well as for evaluating proposed process and facility changes to ensure that protective features in the process are not compromised. 
The Avon Refinery has a comprehensive program to help ensure that hazards associated with the various processes are identified and controlled.  Each process is systematically examined using a technique known as pro 
cess hazard analysis, or PHA.  A team of experienced operators, engineers, and other specialists conducts the analyses.  This team systematically identifies and evaluates hazards of the process as well as existing accident prevention and mitigation measures and makes suggestions for additional prevention and/or mitigation measures when they believe such measures are necessary. 
The PHA teams recommendations are then reviewed and with management personnel for resolution.  Implementation of actions 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 the highest priority.  Actions implemented in response to PHA team findings are tracked until they are completed.  The final resolution of each finding is documented and retained. 
The process hazard analysis for each process unit is updated and re-validated at least every five years.  The results and findings o 
f these updates are documented and retained.  Once again, any team findings are reviewed with management personnel for resolution and any actions that result are tracked until they are completed.   
The Avon Refinery utilizes written procedures that address various phases of process operations including (1) initial startup of a newly constructed process, (2) unit startup, (3) normal operations, (4) temporary operations, (5) normal shutdown, and (6) emergency shutdown.  These procedures provide the basis for consistent initial or refresher training of operators.  The procedures are managed by operating personnel and are updated as necessary to reflect changes and new information.  Operating procedures are reviewed annually to verify that they are current, updated, and accurate.  
Operating procedures and operating manuals are available in hard copy format in each process unit control room. 
To complement the written operating procedures, the Avon 
Refinery has a comprehensive training program for employees involved in operating a process.  New employees must successfully complete 4 weeks or more of basic training on refinery operations before receiving their unit-specific training.  Basic training addresses applied sciences, job fundamentals, operating skills, and understanding basic refining processes.  The time necessary to successfully complete unit-specific training varies with the requirements of each job and the candidate's previous job experience.  It typically takes 8-24 weeks to qualify for a specific operating post.  Throughout the training process, candidates must continue to qualify by passing written and practical tests, thereby demonstrating understanding and retention of the training materials.  Qualification for all operating posts within a process area can take up to 3 years. 
Refresher training on operating procedures is provided to operating employees at least every three years, and refresher safety training  
is performed annually.  In addition, training emphasizing specific topics is performed as necessary (for example, furnace operation, dock operations, etc.).  Prior to the commissioning of new or modified equipment, written operating procedures are developed and training is provided to affected operating personnel.  Operating personnel also receive training in emergency response and fire fighting procedures.   
The first step in a successful mechanical integrity program is ensuring that equipment and processes are properly designed for their intended use.  The Avon Refinery utilizes specific written procedures and design criteria for its operating equipment.  These criteria are contained in Engineering Standards -- referenced to recognized industry standards (such as API, ASME, ANSI, and NFPA) -- or specified by engineering firms with expertise in a specific area of design.   
The Avon Refinery has well-established practices and procedures to m 
aintain pressure vessels, storage tanks, piping systems, relief and vent systems, instrumentation and emergency shutdown systems, pumps, and compressors in proper operating condition.  The basic elements of this program include: (1) appropriate training or equivalent work experience for those responsible for procuring, installing, maintaining, inspecting, and repairing process equipment, (2) developing maintenance and testing procedures, (3) performing appropriate inspections and tests, (4) correcting identified deficiencies, and (5) applying quality assurance measures.   
These activities involve many specialists, including Mechanical Engineers, Metallurgical Engineers, Pressure Vessel and Welding Inspectors, and our maintenance mechanics (for example, Machinists, Electricians, Instrument Technicians, and Welders).  Qualifications of these employees depend on the needed type and level of expertise.  The qualifications include either a four-year degree at an accredited college or equiv 
alent work experience, certification by the governing board in their specialty, or journeyman level skills.  In addition to their specialized education and training, employees and contractors working in the area of mechanical integrity receive summary training on process hazards, safety and health hazards, applicable maintenance procedures, and safe work practices. 
Predictive maintenance inspections and tests are performed on equipment to help ensure that it functions as intended and to verify that equipment is within acceptable limits (for example, adequate wall thickness for pressure vessels).  If a deficiency is identified, necessary actions are taken to address the deficiency, up to and including shutting down and removing the equipment from service for repair or replacement.   
Another integral part of the mechanical integrity program is quality assurance.  The Avon 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 Avon 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, and 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 is permitted. 
The Avon Refinery utilizes contractors to supplement its maintenance workforce and provide additional expertise and resources for specialty tasks or peak work periods (maintenance turnarounds for example).  Because some cont 
ractors work on or near process equipment, the refinery has procedures in place to ensure that contractors (1) perform the work in a safe manner, (2) have the appropriate knowledge and skills for the tasks they are to perform, (3) are aware of the hazards of the workplace, (4) understand what they should do in the event of an emergency, (5) understand and follow the site safety rules, (6) inform refinery personnel of any hazards that their activities may introduce into the plant, and (7) know what to do if they encounter a hazardous condition in the course of their work.   
The qualification process for new contractors includes a review of the contractor's safety performance and references from other companies that have used the contractor.  Additionally, Tosco personnel perform an audit of the contractor's written safety programs.  This audit is performed by a team consisting of Tosco and contractor employees (usually the Safety Manager and/or Field Safety Supervisor) using a standard 
checklist developed by Tosco.  Any deficiencies in the contractor's safety programs must be corrected to Tosco's satisfaction before a contractor is qualified to bid on work at the refinery. 
Tosco requires that contractor employees complete overview training before being allowed access to our facilities.  These requirements include completion of (1) an 8 hour course on general industrial safety that is given by the Bay Area Training Corporation, and (2) refinery orientation that covers general safety rules, the refinery emergency action plan, the use of the process summary information that Tosco has prepared for each refinery process unit, and training in refinery safe work practices.  Contractors who will work in a lead capacity on energized or pressure containing equipment must also pass a written skill test that is specific to refinery work. 
Tosco periodically audits contractor performance to verify compliance with our requirements.  Deficiencies noted during an audit must be cor 
rected either immediately or within five working days, depending on how severe the deficiency is.  Tosco also periodically conducts audits of the contractor's written safety program.   
The Avon Refinery has a program to manage changes to unit operations.  This system requires that changes to items such as process equipment, chemicals and feedstocks, technology, procedures, and other facility changes are authorized and properly reviewed before being implemented.  Changes are reviewed to (1) ensure that adequate controls are in place to manage and control any new hazards, and (2) verify that existing safeguards are not compromised by the change.  This review process is documented utilizing the Management of Change Form.  Affected chemical hazard information, process operating limits, equipment information, and operating procedures are updated to reflect a change.  In addition, operating and maintenance personnel are provided any necessary training on the change pri 
or to its start-up. 
The Avon Refinery conducts a pre-startup safety review for a new facility or facility modification 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 an additional check to make sure that construction is in accordance with the design specifications and that supporting systems are operationally ready.  A pre-startup safety review involves field verification of the construction and serves a quality assurance function by requiring verification that applicable prevention program requirements are properly implemented.  
The Avon Refinery maintains a detailed written incident investigation procedure.  This procedure ensures that events that resulted in, or could reasonably have resulted in a fire or explosion, toxic gas release, major property damage, environmental loss, or personal injury are p 
romptly investigated.  The goal of each investigation is to determine the facts and develop corrective actions to prevent a recurrence of the event or a similar event.  Investigation findings and recommendations are documented and reviewed with management for resolution.  The final resolution of each finding or recommendation is documented and reviewed with workers who could be affected by the findings.  Any actions resulting from investigations are tracked until they are resolved.  Incident investigation reports are retained for at least 5 years so that the reports can be reviewed during future process hazard analyses.   
To help ensure that the Process Safety Management and accidental release prevention programs are functioning properly, the Avon Refinery periodically conducts audits to verify that the procedures and practices required by the programs are being implemented as intended.  Compliance audits are conducted at least every three years.  Management and fie 
ld personnel participate in the audits in order to verify that practices correspond with written procedures.  The audit team may include employee(s) from other sites and third parties.  The audit team develops findings that are presented to refinery and area management for resolution.  Corrective actions taken in response to audit team findings are tracked until they are complete.  The final resolution of each finding or action is documented, and the two most recent audit reports are retained. 
In addition to the prevention program activities, the Avon Refinery has safety features installed in process units to help (1) contain or control a release, (2) quickly detect a release, and (3) reduce the consequences of, or mitigate, a release.  The following types of devices are used in various processes throughout the refinery to help prevent incidents: relief valves, rupture disks, check valves, excess flow valves, remotely operated valves, flare systems, 
automatic interlocks and shutdown systems, hydrocarbon detectors, manual block valves, process alarms (level, temperature, flow, pressure), and computer-aided control systems.  Additionally, the following types of features are used in various processes throughout the refinery to help mitigate (reduce the effects of) incidents: sprinkler systems, deluge systems, dikes or containment berms, fixed firewater monitors, and fire fighting foam delivery systems.   
The Avon Refinery maintains a written emergency response plan to protect its workers, the public, and the environment.  The program includes procedures for responding to the release of regulated substances, including the possibility of a fire or explosion.  The procedures address various aspects of emergency response including notification of local emergency response organizations, proper first-aid and medical treatment for exposures, evacuation and shelter-in-place plans, accounting for personnel after an evacu 
ation, notifications to regulatory agencies, and post incident cleanup and decontamination.  The Avon Refinery utilizes the Incident Command System in cooperation with local emergency response personnel.   
The refinery also has procedures that address the maintenance, inspection, and testing of emergency response equipment, as well as instructions and training that addresses the use of the equipment.  Employees receive training in these procedures as necessary to perform their emergency response duties.  The emergency response program is updated as necessary to reflect changes in refinery processes and suggested improvement.  Training on changes to the plan is given to affected employees. 
The Avon Refinery maintains a qualified fire brigade, an oil spill response team, a hazardous materials team, and a rescue team.  Additionally, several refinery employees are certified emergency medical technicians.  Frequent training and participation in emergency response drills ensures the readin 
ess of the response organization. 
The emergency response program for the Avon Refinery is coordinated with Contra Costa Health Services, Contra Costa Consolidated Fire Protection District, and the Contra Costa County Office of Emergency Services.  This coordination includes periodic meetings with local emergency response officials and other industry representatives.  The Avon Refinery has around-the-clock communications capability with appropriate emergency responders.  This provides a means of notifying the public of an incident and facilitating a quick response. 
Continuous Improvement: The Avon Refinery continuously seeks and evaluates methods to improve the safety of its operations.  Recommendations from audits, incident investigations, process hazard analyses, or employee suggestions provide opportunities to enhance the safety of the refinery.  Improvements in technology provide another opportunity to enhance facility safety.  For example, the r 
efinery discontinued use of gaseous chlorine several years ago when less hazardous substitutes became viable.   
Year 2000 (Y2K) Preparedness: Tosco Corporation and the Avon Refinery have developed Y2K Task Forces to investigate, develop, and implement plans to minimize any disruption that might occur because of Y2K.  Computer software and hardware systems are being reviewed for Y2K compliance, and contingency pre-plans are being developed to address any potential in-plant or supplied utility failures.
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