Chevron Phillips Philtex-Ryton Plant - Executive Summary
The Philtex/Ryton plant has a long-standing commitment to worker and public safety. This commitment is demonstrated by the resources invested in accident prevention, such as training and consideration of 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 Philtex/Ryton Plant, located in Borger, Texas, operates a variety of processes to produce specialty chemicals and plastics. The specialty chemicals units of the Philtex plant produce organo-sulfur compounds, high purity hydrocarbons, solvents and diversified chemicals. The plastics unit produces Ryton? plastic (the Ryton unit does not contain a regulated substance
covered by the Risk Management Program regulation). The chemical
plant has several regulated flammables (i.e., propane, butane, propylene) and toxics (i.e., hydrogen sulfide, sulfur dioxide, methyl mercaptan).
HAZARD ASSESSMENT RESULTS
The worst-case scenario (WCS) associated with toxic substances is a catastrophic release of the entire contents (280,000 lbs.) of sulfur dioxide (SO2) from the SO2 storage tank. Engineering and administrative controls limit the amount in the storage tank to a maximum quantity of 282,000 pounds. Although we have numerous controls to prevent such releases and to manage their consequences, no credit for administrative controls or passive mitigation measures was taken into account in evaluating this scenario. The maximum distance to the toxic endpoint of 3-ppm (0.0078 milligrams per liter) for this WCS is 25 miles.
The alternative release scenario (ARS) for SO2 is a blowout of a pressure gauge on a transfer line from the SO2 storage tank. The 5-minute release duration is the approximate time necessary for the
operator to detect the leak and to isolate this section of the transfer line. Approximately 30 pounds per minute SO2 would be released. No other mitigation measures were taken into account in evaluating this scenario. The distance to the toxic endpoint of 3 ppm (0.0078 milligrams per liter) for this ARS is 0.43 miles. (Note: the 5-year accident history indicates the largest release of SO2 was 3,690 pounds. This was not a direct release of SO2. The SO2 was a by-product of combustion of the burning sulfolene. Sulfolene (not a highly hazardous substance), was part of the released chemicals which burned in the ensuing fire. The SO2 released in this type of scenario is diluted with other combustion products and rapidly dispersed by the heat and turbulence of the flame. The off-site impact is much lower than predicted by air dispersion modeling of spilled pure SO2.).
The WCS associated with a release of flammable substances is a vapor cloud explosion (VCE) involving the maximum inte
nded inventory of the largest storage tank containing 1,3 butadiene.
Administrative and engineering controls are in place to limit the inventory in the storage tank to 94% of maximum, or 210,000 pounds. This WCS assumes the entire inventory is released, vaporizes, and ignites, resulting in a vapor cloud explosion. The maximum distance to the 1-psi endpoint for this WCS is 0.47 miles. Although we have numerous controls to prevent such releases and to manage their consequences, no credit for passive or active mitigation measures was taken in account in evaluating this WCS.
The ARS for flammable substances at Philtex is a VCE resulting from the release of butadiene from a transfer line (61,000 lb released over a 10-minute period). The release is expected to be isolated by the operators within 10 minutes (active mitigation). The distance to the 1-psi endpoint for this event is 0.1 miles. This event was selected as being a practical scenario for use in emergency planning and resp
onse. This ARS scenario was one of the scenarios evaluated during the Building Siting study conducted at the plant in 1998. As a result of the Building Siting study, hydrocarbon detectors, alarms and interlocks to automatically close isolation valves were added to a number of hydrocarbon storage tanks, including the butadiene storage tank. This active mitigation measure was not taken into account in evaluating this scenario.
Figures 1 and 2 (following pages) graphically present the hazard assessment results for the toxic and flammable WCS and ARS events, respectively.
The following table summarizes the results of the hazard assessments for the remaining toxic substances at the plant.
Allyl Alcohol WCS 0.6 miles and ARS-0.6 miles
Hydrogen Sulfide WCS 13 miles and ARS 1.9 miles
Methyl Mercaptan WCS 12 miles and ARS 0.7miles
Piperidine WCS12 miles ARS 2.8 miles
The hazard assessments for the remaining flammables at the plant yielded a shorter distance to endpo
int as compared to the flammable WCS described above.
GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM STEPS
The following is a summary of the general accident prevention program in place at the Philtex/Ryton plant. Because processes at the plant that are regulated by the EPA RMP regulation are also subject to the OSHA Process Safety Management (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 Philtex/Ryton plant encourages employees to participate in all facets of risk 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 plant accident prevention program. Specific ways that employees can be involved in the accident
prevention program are documented in the employee participation element of the Philtex/Ryton Risk Management system and in the employee participation section of all other risk management elements. In addition, the plant has a number of initiatives under way that address process safety and employee safety issues. These initiatives include forming teams to promote both process safety and personal safety. The teams typically have members from various areas of the plant, including operations, maintenance, engineering and plant management.
Two key areas for employee participation include the employee behavioral safety process and OSHA's Voluntary Protection Program. Philtex Plant received the National Association of Manufacturers (NAM) Award for Workplace Excellence in the large manufacturing category in 1997. This award recognizes Philtex's use of a behavioral-based safety process (POWER, People Observing Work, Eliminating Risk). This employee driven process has achieved a 65% red
uction in recordable injuries since implementation. An OSHA VPP site inspection team reviewed the Philtex/Ryton Plant in November 1998. Induction of the plant into the VPP program is expected in the first half of 1999 as a result.
Process Safety Information
The Philtex/Ryton Plant keeps a variety of technical documents that are used to 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 plant are assigned responsibility for maintaining up-to-date process safety information. Process safety information reference documents are readily available as part of the written employee participation plan to help employees locate any necessary process safety information.
Chemical-specific information, including exposure hazards and emergency response/exposure treatment considerat
ions, is provided in material safety data sheets (MSDSs). For specific process areas, the plant has documented safety-related limits for specific process parameters (e.g., temperature, level, composition) in the unit-specific Process Safety Information (PSI) document. The plant 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 plant 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 featu
res in the process are not compromised.
Process Hazard Analysis
The Philtex/Ryton Plant 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 Philtex/Ryton Plant 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 when the team believes such measures are necessary.
The PHA team findings are forwarded to local and corporate 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 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, Philtex/Ryton 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 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 ret
Philtex/Ryton 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 annually 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 process.
In addition, Philtex/Ryton maintains a Process Safety Information document that provides 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, Philtex/Ryton has implemented a comprehensive training program for all employees involved in operating a process. New employees receive basic training in plant 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. This refresher training is conducted at least every 3 years. All of this training is documented for each operator, including the means used to verify tha
t the operator understood the training.
Philtex/Ryton uses contractors to supplement its work force during periods of increased maintenance or construction activities. Because some contractors work on or near process equipment, the plant 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 plant 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, Philtex/Ryton evaluates contractor safety programs and performance during the selection of a contractor. Plant personnel periodicall
y monitor contractor performance to ensure that contractors are fulfilling their safety obligations.
Pre-startup Safety Reviews (PSSRs)
Philtex/Ryton conducts a PSSR for any new facility or 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 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.
Philtex/Ryton has well-established practices and procedures to maintain pressure v
essels, 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
acceptable 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. Philtex/Ryton 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.
Philtex/Ryton has developed a team-based defect elimination process known as PRIDE (Philtex/Ryton Integrated Defect Elimination). The objective of this employee driven process is to eliminate equipment failures through predictive and preventive maintenance. As this process continues to take hold we expect continuous improvement in ope
rating reliability and safety.
Safe Work Practices
Philtex/Ryton 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) procedures 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
Philtex/Ryton has a comprehensive system to manage changes to processes. This system requires that changes to items such as process equipment, chemicals, tech
nology (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.
Philtex/Ryton 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 plant 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.
To help ensure that the accident prevention program is functioning properly, Philtex/Ryton 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 that are forwarded to plant 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.
In addition to the OSHA PSM elements described above, Philtex/Ryton incorporates the elements of Phillips Petroleum's Process for Safety & Environmental Excellence and OSHA's Voluntary Protection Program into a single, integrated plant Risk Management program. The elements of these two management processes are:
OSHA VPP ELEMENTS(VOLUNTARY PROTECTION PROGRAM) and PSEE ELEMENTS(PROCESS FOR S/E EXCELLENCE)
VPP (1) MANAGEMENT COMMITMENT AND PLANNING and PSEE (1) ROLES AND RESPONSIBILITIES
VPP (2) ACCOUNTABILITY SYSTEMS and PSEE (2) TRAINING
VPP (3) DISCIPLINARY PROGRAM and PSEE (3) INDUSTRIAL HYGIENE & HEALTH
VPP (4) INJURY RATES and PSEE (4) EMPLOYEE OWNERSHIP
VPP (5) EMPLOYEE PARTICIPATION and PSEE (5) BEHAVIO
VPP (6) SELF INSPECTIONS andPSEE (6) STANDARDS & PROCEDURES
VPP (7) EMPLOYEE HAZARD REPORTING SYSTEMS and PSEE (7) ENGINEERING DESIGN
VPP (8) ACCIDENT/INCIDENT INVESTIGATION andPSEE (8) MEASUREMENT
VPP (9) JSA/PROCESS REVIEW and PSEE (9) AUDITS
VPP (10) SAFETY & HEALTH TRAINING andPSEE (10) CONTRACTOR PERFORMANCE
VPP (11) PREVENTATIVE MAINTENANCE andPSEE (11) INCIDENT INVESTIGATION
VPP (12) EMERGENCY PROGRAMS/DRILLS andPSEE (12) RISK MANAGEMENT
VPP (13) PERSONAL PROTECTIVE EQUIPMENT and PSEE (13) MECHANICAL & OPERATING
VPP (14) HEALTH PROGRAMS andPSEE (14) COMMUNITY INVOLVEMENT
VPP (15) SAFETY & HEALTH STAFF INVOLVED WITH CHANGES and PSEE (15) REGULATORY ASSESSMENT AND
VPP (16) CONTRACTOR SAFETY and PSEE (16) PRODUCT STEWARDSHIP
VPP (17) MEDICAL PROGRAM and PSEE (17) POLLUTION PREVENTION
VPP (18) SAFETY AND HEALTH STAFF RESOURCES
VPP (19) ANNUAL EVALUATION
As a result of the recent Chevron Chemical Company and Phillips Petroleum Company merger o
f their respective chemical producing facilities, the Philtex-Ryton facility will merge the 17 program elements of Phillips Process for Safety and Environmental Excellence with the 10 elements of the CMA Responsible Care? program. These elements, combined with the OSHA PSM elements, ensure a comprehensive accident prevention program.
CHEMICAL-SPECIFIC PREVENTION STEPS
The processes at Philtex/Ryton have hazards that must be managed to ensure continued safe operation. The accident prevention program summarized previously is applied to all EPA RMP covered process at the plant. 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, Philtex/Ryton 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 t
ypes of safety features are used in various processes:
Hydrocarbon detectors with alarms
Chemical specific detectors with alarms
Process relief valves that discharge to a flare to capture and incinerate episodic releases Scrubber to neutralize chemical releases Valves to permit isolation of the process (manual or automated)
Automated shutdown systems for specific process parameters (e.g., high level, high temperature, release detection) Vessel to permit partial removal of the process inventory in the event of a release (e.g., dump tank) Curbing or diking to contain liquid releases Redundant equipment and instrumentation (e.g., uninterruptible power supply for process control system, backup firewater pump) Atmospheric relief devicesRelease Mitigation
Fire suppression and extinguishing systems
Deluge system for specific equipment
Trained emergency response personnel
Personal protective equipment (e.g., protective clothing, self-containe
d breathing apparatus)
Blast-resistant buildings to help protect control systems and personnel
FIVE-YEAR ACCIDENT HISTORY
Over the past 5 years there have been no RMP events with offsite effects. There has been 1 RMP event (1996) with onsite effects. Every incident is carefully investigated to determine ways to prevent similar incidents from occurring.
EMERGENCY RESPONSE PROGRAM INFORMATION
Philtex/Ryton 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 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 and the public if a rele
ase occurs, and post-incident cleanup and decontamination requirements. In addition, Philtex/Ryton 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 plant processes or other plant 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 Philtex/Ryton is coordinated with the Hutchinson County Local Emergency Planning Committee (LEPC) and the Panhandle Emergency Response System (PERS). This coordination includes periodic meetings of the committee, which includes local emergency response officials, local governmen
t officials, and industry representatives.
Philtex/Ryton has around-the-clock communications capability with appropriate LEPC officials and emergency response organizations (e.g., fire department). 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, Philtex/Ryton conducts periodic emergency drills that involve the LEPC and emergency response organizations.
PLANNED CHANGES TO IMPROVE SAFETY
Philtex/Ryton resolves all findings from PHA's, some of which result in modifications to the process. The following types of changes are planned:
Revised process instrumentation and/or controls in the Commercial Products Unit (CPU)
Consolidate unit control rooms to centralized control room (blast resistant building)
Hydrocarbon release detection systems and alarms (some with automatic shutdowns) on
several vessels containing flammables Excess flow device on vessels containing fl
Restrictive orifices in level gauges on vessels containing flammables New flare system for A-Battery vessels
Safety film on windows of occupied buildings
Additional toxic gas sensors and alarms
Implement H2S (CPU), SO2 and 1,3 butadiene pipe system inspection program (in addition to other hazardous services)
New plant breathing air system
PPU and Unit 5.2 hydrocarbon detectors connected to building ventilation system
Tank level and pressure instrumentation centralized in Distributed Control System (DCS)
New plant emergency alert and notification system
Automatic shutoffs connected to hydrocarbon detectors at railcar loading facility
Philtex/Ryton chose the conservative method for hazard assessment by utilizing EPA's RMP*Comp model. The results of RMP*Comp may not closely match the results you obtain running the same release scenario in a more sophisticated air dispersion model. RMP*Comp is a planning tool designed to help you to easily identify high-priority hazards. It re
lies on very simplified and generalized calculations. In contrast, models like ALOHA and DEGADIS are intended to give as accurate an estimate as possible of the extent of the area that might be placed at risk by a particular chemical release.