Crown Central Petroleum, Houston Refinery - Executive Summary

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Risk Management Plan:    Executive Summary 
   The Crown Central Petroleum Corporation (Crown) 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. 
   The Crown refinery, located in Pasadena, Texas , operates a variety of processes to produce petroleum products (e.g., refinery grade propylene, gasoline, fuel oil, and coke) from raw crude oil.  The refinery has several regulated flammables, such as hydrogen, methane, ethanes, propanes, butanes, a 
nd pentanes.  In addition, the refinery uses chlorine for algae control in cooling towers  and hydrogen fluoride in the making of gasoline, which are also regulated substances. 
   EPA has tailored the requirements of the worst case scenario (WCS) assessment into three tiers and Crown's risk management program falls into Program 3, because of its industry type - refining, and its existing coverage under the Occupational Safety and Health Administration (OSHA) process safety management program.  Crown's  WCS assessment associated with toxic substances in Program 3 processes at the refinery is a catastrophic failure of the hydrofluoric (HF) acid storage drum , resulting in a release of 50,000 pounds of HF gas from its storage drum over a 10-minute period.  Although we have numerous controls, such as water sprays, hydrogen fluoride detectors, hydrocarbon detectors, and hydrogen fluoride sensitive paint,  to prevent or warn of such releases and to manage their cons 
equences,  we have not taken into account  administrative controls or passive mitigation measures  in evaluating this WCS scenario.  The maximum distance to the toxic endpoint, which is the level of severity of a toxic release below which no harm should come to the community,  of  0.016 milligrams per liter for this WCS is 9.3 miles as calculated by the EPA Offsite Consequence Analysis. 
   The alternative release scenario (ARS) for HF is the failure of the seal of the Alkylation Unit Depropanizer feed pump, resulting in a release of less than 4.0 pounds of HF gas over a 1-minute period.  The 1-minute release duration is the approximate time necessary for monitors to detect HF and for the isolation valves to isolate the pump and stop the release.  No other mitigation measures were taken into account in evaluating this scenario.  The maximum distance to the toxic endpoint of  0.016 milligrams per liter for this ARS is 0.19 miles as calculated by the EPA Offsite Consequence Analysis. 
WCS associated with a release of flammable substances in Program 3 processes at the refinery is a vapor cloud explosion (VCE) involving the full inventory of the largest storage tank containing normal butane.  We do not  limit the storage inventory in the tank and therefore, the WCS assumes the full tank inventory of 2,900,000 pounds is  released, completely vaporizes, and ignites, resulting in a VCE.  The maximum distance to the 1-PSI (pounds per square inch) endpoint for this WCS is 1.2 miles as calculated by the EPA Offsite Consequence Analysis.  This 1-PSI endpoint is the point from American Petroleum Institute's Recommended Practice 752 that partial demolition of houses can be expected.  Although we have numerous  controls, such as dikes, mechanical inspections, water spargers, and visual inspection every four hours, to prevent such releases and to manage their consequences, no credit for active or passive mitigation measures was taken into account in evaluating this WCS. 
   The a 
lternative release scenario (ARS) for flammable substances at the refinery is a VCE resulting from the release of 61,000 pounds of Isobutane from a ruptured transfer line over a 60-minute period.  The release is expected to be isolated by the operators within 60 minutes (active mitigation).  The leak would be contained by a dike (passive mitigation).  The amount of Isobutane involved in the vapor cloud explosion is calculated to be 1900 pounds.  The maximum distance to the 1-PSI endpoint for this event is 0.067 miles as calculated by the EPA Offsite Consequence Analysis.  This event was selected as a more likely scenario than a WCS and therefore is used  in emergency planning and response. 
   The alternative release scenario (ARS)  for chlorine at the refinery is a tubing leak from a 1 ton cylinder.  The leak could last for 2-4 hours based on operator field checks and would emit up to 9.0 pounds per minute.  The maximum distance to the toxic endpoint of 0.0087 milligrams per liter for t 
his ARS is 0.1 miles as calculated by the EPA Offsite Consequence Analysis.  A WCS for chlorine is not provided because EPA has asked companies to prepare one WCS for all regulated toxic substances, selecting the substance with the highest potential for off-site consequences, as long as the same public receptors would be affected.  This WCS is addressed above for HF. 
   The Crown  refinery has an excellent record of accident prevention over the past 5 years; the frequency of accidental releases has decreased.  None of the incidents that have occurred have resulted in offsite consequences.  Over the last five years Crown has had ten Hydrogen Fluoride incidents and one chlorine incident.  Each of the events consists solely of an injury recordable on the refinery's OSHA 200 Log  for chemicals and flammable substances subject to the RMP program.  We investigate every incident very carefully to determine ways to prevent similar incidents from occurring. 
of the hydrogen fluoride incidents consisted of no more than 2-4 drops of acid coming into contact with an employee.  The chlorine incident consisted of only a whiff  of the gas.  The amount of hydrogen fluoride consisted of no more than 0.004 pounds per incident. 
   The following is a summary of the general accident prevention program in place at Crown's 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. 
Employee Participation 
   Crown 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 (PH 
A) team.  Employees have access to all information created as part of the refinery accident prevention program.  Specific ways that employees can be involved in the accident prevention program are documented in an employee participation plan that is maintained at the refinery and addresses each accident prevention program element. 
Process Safety Information 
   Crown maintains and updates a variety of technical documents that are used to  ensure 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 (MSDS). For specific process areas, t 
he refinery has documented safety-related limits for certain process parameters, such as , temperature, level, and composition, in its Unit Operating Procedures manuals.  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 evaluating proposed process and facility changes to ensure that safety features in the process are not compromised. 
   Employees involved with operating a process are tra 
ined to make them familiar with all of the process safety information.  Any time that changes or updates are made to the process safety information, all such employees are informed and familiarized.   
Process Hazard Analysis (PHA) 
   Crown 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. 
   Crown's refinery primarily uses the hazard and operability (HAZOP) analysis technique to perform these evaluations, which is part of the OSHA Process Hazard Analysis program.  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 measures when the team believes such measures are necessary. 
   The PHA team findings are forwarded to management for 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 immediate attention.  All approved mitigation options being implemented in response to PHA team findings are tracked until they are completed.  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, Crown's 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 freque 
ncy until the process is no longer operating.  The results and findings from these updates are documented and retained.  Once again, the team findings are forwarded to management for consideration and the final resolution of the findings is documented and retained. 
Operating Procedures 
   Crown's 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 to insure that they are current and accurate.  These procedures are also updated whenever a change is implemented that affects the process chemicals, technology, or equipment in an operating process. 
   In addition, Crown's refinery maintains in its Unit Operating Procedures M 
anuals procedures that provide guidance on how to respond to upper or lower limit exceedances for specific process or equipment parameters.  This information, along with written operating procedures is readily available to operators in the process unit and for other personnel to use as necessary to safely perform their job tasks. 
   To complement the written procedures for process operations, the Crown 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 per 
iodically receive refresher training on the emergency operating procedures to ensure that their skills and knowledge are maintained at an acceptable level.  This refresher training is conducted at least every 2 years.  All of this training is documented for each operator, including the means used to verify that the operator understood the training. 
   The refinery 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 Crown 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.  The company has formed a Partnership for Safety program which is a safety effort involving representatives from all of the contract companies doing work in the refinery.  This group meets regularly to discuss safety performance and make suggestions to improve safety practices in the refinery. The Partnership for Safety program is in addition to the company's monthly management safety meeting. 
Pre-startup Safety Reviews (PSSRs) 
   The Crown refinery conducts a PSSR for any new facility or significant facility modification 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 i 
nto service.  This review provides one additional check to make sure that any change 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. 
Mechanical Integrity 
   The Crown refinery 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 mainta 
ins 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 acceptable limits (e.g., adequate wall thickness for pressure vessels).  Inspections are performed both "on-line" and when the equipment is scheduled down for inspection and repairs.  If a deficiency is identified, employees will correct the deficiency before placing the equipment back into service (if the equipment has not exceeded its useful life), or a Management of Change team organized pursuant to OSHA's PSM prog 
ram, 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.  Crown's 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. 
Safe Work Practices 
   The Crown 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 en 
sure 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 Crown refinery has a comprehensive system to manage changes to processes.  This system requires that changes to items such as process equipment, chemicals, technology (including process operating conditions), procedures, and other facility changes are 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 t 
raining on the change. 
Incident Investigation 
   Crown  promptly investigates all incidents that resulted in, or reasonably could have resulted in, a fire/explosion, toxic gas release, major 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, develops recommendations to prevent a recurrence, and forwards these results to refinery management for resolution.  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. 
Compliance Audits 
   To help ensure that the accident prevention program is functioning properly, Crown 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 in the audit function.  The audit team develops findings that are forwarded to refinery management 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 two most recent audit reports are retained. 
   The processes at the Crown 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 Crown refinery.  Coll 
ectively, 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, Crown has safety features on many units to help (1) quickly detect a  release, (2) contain/control  a release, and (3) reduce the consequences of (mitigate) a release.  The following types of safety features are used in various processes: 
Release Detection 
1.    Hydrocarbon detectors with alarms 
2.    Hydrofluoric acid leak detectors with warning mechanisms 
3.    Hydrogen sulfide leak detectors with warning mechanisms 
4.    Video camera surveillance 
Release Containment/Control 
1.    Process relief valves that discharge to a flare to capture and incinerate episodic releases 
2.    Scrubber to neutralize chemical releases 
3.    Valves to permit isolation of the process (manual or automated) 
4.    Automated shutdown systems for specific process parameters (e.g., high level, high temperatur 
5.    Vessel to permit partial removal of the process inventory in the event of a release (e.g., dump     tank) 
6.    Curbing or diking to contain liquid releases 
7.    Redundant equipment and instrumentation (e.g., uninterruptible power supply for process control     system, backup firewater pump) 
8.    Atmospheric relief devices 
Release Mitigation 
1.    Fire suppression and extinguishing systems 
2.    Water spray system for specific equipment 
3.    Trained emergency response personnel 
4.    Personal protective equipment (e.g., protective clothing, self-contained breathing apparatus) 
   The Crown 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 address all aspects of emer 
gency 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 and the public if a release occurs, and post-incident cleanup and decontamination.   In addition, Crown's 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 overall emergency response program for the Crown refinery is coordinated with the Pasadena, Texas, Local Emergency Planning Committee (LEPC).  This coordination includes periodic meetings of the committee, which includes local emergency response official 
s, local government officials, and industry representatives.  Crown's refinery has around-the-clock communications capability with appropriate LEPC officials and emergency response organizations such as the Channel Industries Mutual Aid (CIMA) organization.  CIMA consists of approximately 110 industries and local fire departments which stand ready to provide emergency response teams in the event they are needed.  This provides a means of notifying the public of an incident, if necessary, as well as facilitating quick response to an incident.  In addition to periodic LEPC meetings, the Crown refinery conducts periodic emergency drills that involve the LEPC and emergency response organizations, and the refinery provides  refresher training to local emergency responders regarding the hazards of regulated substances in the refinery. 
   The Crown refinery resolves all findings from PHAs, some of which result in modifications to the process.  The following t 
ypes of changes are planned: 
Revised process instrumentation and/or controls 
Revisions to personnel training programs 
Revise written operating procedures 
Additional use of "carsealing" on isolation valves in the path of the pressure relief systems 
Drug and Alcohol training for supervisors and managers 
HF Acid safety awareness 
Forklift training to train the trainer 
Front end loader train the trainer 
Aerial lift train the trainer 
Chemical Hygiene Plan training for lab personnel
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