Canute Natural Gas Processing Plant - Executive Summary |
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Transok / Canute Gas Plant RMP / Executive Summary A. Accidental Release Prevention and Response Policies The Canute Gas Plant has a 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. Transok's policy for the design and operation of gas plants is to implement reasonable controls to prevent foreseeable releases of regulated substances. However, if a release does occur, trained personnel will respond to and attempt to control and contain the release. B. Description of the Stationary Source and Regulated Substances Transok operates the Canute Gas Plant located 7 miles south and 1 mile west of Canute, Oklahoma in Washita County. The Canute Plant receives natural gas with some condensed hydrocarbon liquids (i.e. condensate) from production wells by pipeline system. The plant separates eth ane, propane, butanes, and higher molecular weight hydrocarbon components from natural gas by liquefying them at cryogenic temperatures. The natural gas minus these liquefied components (called "residue gas") is delivered back into the pipeline system for ultimate use as fuel. The natural gas liquids (NGL's or Raw Mix) are sold separately for petrochemical feedstock, fuel, and other uses. The NGL's are delivered into a Koch Company pipeline connected to the plant. The Canute Gas Plant was evaluated to determine if any regulated flammable or toxic substances exceeded the threshold quantity. Based on process knowledge, Transok identified the regulated substances and quantities kept on site. The chemicals, largest quantities on site, and associated threshold quantities are presented in Section II - Accident Release Prevention Program, Table 1. Listed flammable substances, which are stored above threshold quantities at the Canute Gas Plant, are NGL's (product), methane and condensa te. However, Transok has determined that condensate has an NFPA rating of 3, which exempts this mixture from threshold determination. There are no listed toxic substances stored above threshold quantities at the Canute Plant. Based on worst-case analysis, the distance to the endpoint exceeds the distance to public receptors. In addition, the Canute Gas Plant is subject to the OSHA Process Safety Management Program (PSM). Therefore, the Canute Gas Plant is classified as a Program 3 process under the Accident Release Program C. Offsite Consequence Analysis Results 1. Worst-Case Releases Flammable Substances The endpoint for a worst-case scenario (WCS) release of a flammable substance is a 1 psi overpressure (i.e., 15.7 psia), resulting from a vapor cloud explosion. The Accidental Release Prevention (ARP) Program requirement for flammables assumes an instantaneous release and vapor cloud explosion. A yield factor of 10 percent of the available energy released in the explosio n shall be used to determine the distance to the explosion endpoint. Since the worst-case release scenario for a flammable substance is based on the assumption that the entire quantity of the substance forms a vapor cloud, passive mitigation systems are not applicable. The worst-case release scenario is from the NGL storage tank (i.e. product surge tank) with an endpoint 1 psi overpressure distance of 0.39 miles. This is based on using the Environmental Protection Agency (EPA) equations found in the "RMP Offsite Consequence Analysis Guidance" dated May 24, 1996. The storage capacity of the largest (& only) NGL storage tank is 35,000 gallons, which is limited to 80% or 28,000 gallons by administrative controls. It assumes the entire contents of the tank (28,000 gallons or 110,110 pounds) is released instantaneously and is involved in the vapor cloud explosion. Toxic Substances The Canute Gas Plant does not have any toxic substances above the threshold quantity; therefore, analys is of worst-case release scenarios for toxic substances is not required. 2. Alternative Releases Alternative releases scenarios are those that are more likely to occur than the worst-case release scenario. Alternative release scenarios for toxic substances should be those that lead to concentrations above the endpoints beyond the facility's fenceline. Alternative release scenarios for flammable substances should have the potential to cause substantial damage, including on-site damage. Flammable Substances A single alternative release scenario for all flammable substances is required under the ARP program. A hypothetical, but likely to occur, release scenario has been identified for NGL's as follows: A 2 inch valve on the 35,000 gallon, 250 psi, product surge tank fails and releases contents undetected for a period of 30 minutes. This volume released of 30,785 pounds then participates in a vapor cloud explosion resulting in a 1 psi overpressure endpoint distance of 0.25 mile s. This is based on EPA equations found in the "RMP Offsite Consequence Analysis Guidance" document. Toxic Substances The Canute Gas Plant does not have any toxic substances held above the threshold quantity. Therefore, analysis of each regulated toxic substance is not required. D. General Accidental Release Prevention Program The following is a summary of the accident prevention program in place at the Canute Gas Plant. The processes at the gas plant are regulated by EPA's Risk Management Program (RMP) regulation. They are also subject to the Occupational Safety and Health Administration's (OSHA's) 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 Release Prevention (APR) Program under EPA's RMP. 1. Employee Participation Active employee participation and involvement in the development and implementation of the Canute Gas Plant's PSM program is an important ste p toward achieving the objective to prevent or minimize the consequences of catastrophic releases of the flammable substances at the plant. Employee involvement will help ensure that all perspectives regarding PSM are considered, and that the best ideas are implemented. Open communications are encouraged between supervisors and employees regarding all safety and health issues. In addition, this is mandated as part of Transok Corporate Policy #SA4 - Employee Participation and is further identified in Section II, Part C of the PSM Manual. The Canute Gas Plant strongly encourages employees to participate in all facets of process safety management and accident prevention. Examples of this include a cross-section of employees and management ad hoc teams participating in: * Process Hazard Analysis * Pre-Startup Safety Reviews * Audits * Operating Procedures Development The Canute Gas Plant also actively seeks employee involvement in the development and conduct of all accident preventi on activities through existing safety programs. Accident prevention is discussed at monthly safety meetings and/or during special training sessions if necessary. Employee suggestions on improving safety processes are encouraged at these meetings. Specific ways that employees can be involved in the accident prevention program are also documented in Section II, Part C of the PSM Manual. 2. Process Safety Information Complete and accurate written process safety information (PSI) concerning process chemicals, process technology, and process equipment is essential to an effective PSM and RMP program and to completing and maintaining a process hazard analysis (PHA). The PSI will be useful to the operators; the team performing the PHA; those in charge of training; contractors; those conducting pre-startup safety reviews; and those in charge of updating the emergency preparedness plans. Process Safety Information is readily available to all employees. The Canute Gas Plant keeps a variet y 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. The documents include the PSM Process Hazard Analysis, process flow diagrams, piping & instrument diagrams, vendor data books (equipment specifications & operation), description of process chemistry, inventory of hazardous chemicals, operating manual (upper/lower operating limits, startup, shutdown, etc.) and electrical classification drawings. Chemical-specific information, including exposure hazards and emergency response/exposure treatment considerations, is provided in material safety data sheets (MSDS's). The Canute Gas Plant also ensures that operating processes are maintained within limits using process controls and monitoring instruments, highly trained personnel, and protective instrument systems ( e.g., automated shutdown systems). 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. See also Section II, Part D of the PSM Manual. 3. Process Hazard Analysis (PHA) The Canute Gas 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 Canute Gas Plant primarily uses the "What-if / Checklist" method analysis technique to perform these evaluations. The analyses are conducted using a team of people who have extensive 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 the team makes recommendations for additional prevention and/or mitigation measures when the team believes such measures are necessary. The PHA team recommendations are forwarded to local and corporate management for resolution. The PHA team will ensure that potential accident scenarios with a high risk of imminent danger receive immediate attention. All approved mitigation options in response to PHA team recommendations are tracked until they are completed. The final resolution of each recommendation 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 plant 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 recommendations from these updates are documented and retained. Once again, the team recommendations are forwarded to management for consideration, and the final resolution of the recommendations is documented and retained. The details of this program are also identified in Section II, Part E of the PSM Manual. 4. Operating Procedures The Canute Gas Plant 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 determine if they are current and accurate. The procedures are kept current and accurate by revising them as necessary to reflect changes made through the management of change process. The intent of the operat ing procedures is to provide workable, useful, and clearly written instructions for conducting operating activities. To have effective operating procedures, the task and procedures directly and indirectly related to the covered process must be appropriate, clear, consistent, and most importantly, communicated to employees. Operating procedures are specific instructions or details on what steps are taken or followed in caring out the stated procedures. The specific instructions include the applicable safety precautions and appropriate information on safety implications. See also Section II, Part F of the PSM Manual. 5. Training To complement the written procedures for process operations, the Canute Gas Plant has various training programs available for operations personnel. New employees receive basic training in gas plant operations. In addition, all operators periodically receive refresher training on operating procedures to ensure that their skills and knowledge are maintai ned at an acceptable level. New operators are also paired with a senior operator to learn process-specific duties and tasks. After operators demonstrate (e.g., through tests, skills demonstration) 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. See training and certification requirements also in Section II, Part G of the PSM Manual. 6. Contractors The Canute Gas Plant uses contractors to supplement its workforce 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 an orientation session and video that covers (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, Transok evaluates contractor safety programs and performance during the selection of a contractor. Gas plant personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations. Detailed contractor orientation and work rules are also identified in Section II, Part H of the PSM Manual. 7. Pre-Startup Safety Reviews (PSSRs) The Canute Gas Plant c onducts 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 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. See also Section II, Part I of the PSM Manual 8. Mechanical Integrity The Canute Gas Plant has well-established practices and procedures for maintaining process equipment. The basic aspects of this program include: (1) training, (2) developing written pr ocedures, (3) performing inspections and tests, (4) correcting equipment deficiencies, when identified, (5) applying quality assurance measures. In combination, these activities form a system that maintains the mechanical integrity of the process. 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 jobs in a safe manner. Procedures are in place to ensure that work is performed in a consistent manner. 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 a management of change team will review the use of t he 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 Canute Gas Plant incorporates quality assurance measures into equipment purchases and repairs. This helps ensure that new equipment is suitable for its intended use and that proper material and spare parts are used when repairs are made. Mechanical integrity procedures are also covered in Section II, Part J of the PSM Manual. 9. Safe Work Practices The Canute Gas Plant has 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 substances before process piping or equipment is opened, (4) a permit and procedure to control spark-producing activi ties (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. See also Section II, Part K "Hot Work Permit" of the PSM Manual. 10. Management of Change The Canute Gas Plant has a comprehensive system to manage changes to all covered processes. 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 details of the management of change system are also identified in Section II, Part L of the PSM Manual. 11. Incident Investigation The Canute Gas Plant promptly investigates all incidents (no later than 48 hours after incident) 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 management for resolution. Corrective actions taken in response to the investigation team's findings and recommendations are tracked until they are complete. Th e 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. See also Section II, Part M of the PSM Manual. 12. Compliance Audits To help ensure that the accident prevention program is functioning properly, the Canute Gas Plant 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. The audit shall be conducted by at least one person knowledgeable in the process. The audit team develops findings that are forwarded to management for resolution. Corrective actions taken in response to the audit team's findings are tracked until they are complete. The final resolu tion of each finding is documented, and the two most recent audit reports are retained. See Section II, Part O of the PSM Manual. 13. Chemical Specific Prevention Steps The processes at the Canute Gas Plant have hazards that must be managed to ensure continued safe operation. The following is a description of existing safety features applicable to prevention of accidental releases of regulated substances in the facility: Universal Prevention Activities The accident prevention program summarized previously is applied to all RMP-covered processes at the Canute Gas Plant. Collectively, these prevention program activities help prevent potential accident scenarios that could be caused by equipment failures and human errors. Specialized Safety Features The Canute Gas Plant 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 the covered processes: Release Detection 1. Hydrocarbon detectors with alarms. Release Containment/Control 1. Process relief valves that discharge to a flare to capture and incinerate episodic releases 2. Valves to permit isolation of the process (manual or automated) 3. Automated shutdown systems for specific process parameters (e.g., high temperature) 4. Curbing or diking to contain liquid releases 5. Redundant equipment and instrumentation (e.g., uninterruptible power supply for process control system) 6. Atmospheric relief devices Release Mitigation 1. Fire suppression and extinguishing systems 2. Deluge system for specific equipment 3. Personnel trained in emergency procedures 4. Personal protective equipment E. Five -Year Accident History The Canute Gas Plant has an excellent record of accident prevention. The plant was constructed in 1998 with operations commencing in April 1998. Since that time there have been no incidents that have had offsite effects. F. Emergency Response Program Information The Canute Gas Plant maintains written emergency response procedures, which are in place to protect worker and public safety as well as the environment. The procedures are 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 notification of local emergency response agencies if a release occurs and post incident cleanup and decontamination requirements. Employees receive training in emergency procedures. The emergency response procedure is updated when necessary based on modifications made to plant facilities. The emergency response procedure changes are administered through the Management of Change (MOC) process, which includes informing and/or training affected personnel in the changes. The overall emergency response program for the Canute Gas Plant is coordinated with the Washita County, Oklahoma, Local Emerge ncy Planning Committee (LEPC). This coordination includes periodic meetings of the committee, which may include local emergency response officials, local government officials, and industry representatives. The Canute Gas Plant 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, the Canute Gas Plant conducts periodic simulated emergency drills in monthly safety meetings. The Spill Prevention Control and Countermeasure (SPCC) Plan for the plant also identifies emergency response procedures and notification contacts. G. Planned Changes To Improve Safety The Canute Gas Plant resolves all findings from PHAs, some of which result in modifications to the process. The following types of changes are planned over the next few years in response to PHA, safety audit, and incident investigation findings: * Revisions/enhancements to personnel training programs * Revisions to operating procedures * Revisions/enhancements to contractor safety programs * Revisions/enhancements to mechanical integrity program Canute RMP 11 03/11/99 B-5 Executive Summary I) Accidental release prevention and emergency response policies: In this distribution facility, we handle propane which is considered a regulated flammable substance by the EPA. The same properties that make propane valuable as a fuel also make it necessary to observe certain safety precautions in handling propane to prevent unnecessary human exposure, to reduce the threat to our own personal health as well as our co-workers, and to reduce the threat to nearby members of the community. It is our policy to adhere to all applicable federal, state and local rules and regulations. Safety depends upon the manner in which we handle propane combined with t he safe handling procedures that we use and the training of our personnel. Our emergency response program is based upon the NPGA's LP-Gas Safety Handbook, "Guidelines for Developing Plant Emergency Procedures" and "How to Control LP-Gas Leaks and Fires". The emergency response plan, if required, includes procedures for notification of the local fire authority and notification of any potentially affected neighbors. II) The stationary source and regulated substances handled: The primary purpose of this facility is to repackage and distribute propane to both retail and wholesale customers. Propane is used by retail customers as a fuel. Propane can be received by truck transports and rail car and stored in three aboveground tanks. Propane is distributed to retail customers by delivery trucks (bobtails) and to wholesale customers by bobtails and truck transports. We also fill Department of Transportation (DOT) containers for retail customers. This facility has equipment for unload ing transports and equipment to load bobtails, transports and DOT containers. Access to the site is restricted to authorized facility employees, authorized management personnel and authorized contractors. The regulated substance handled at this distribution facility is propane. The maximum amount of propane that can be stored at this plant is 288,288 pounds. Up to three rail tanker cars can also be temporally stored at this facility each with 111,675 pounds of propane. Each rail car can contain up to 30,215 gallons. III) The worst-case release scenario(s) and the alternative release scenario(s), including administrative controls and mitigation measures to limit the distances for each reported scenario. Worst-Case Scenario: - Failure of largest tank when filled to the greatest amount allowed would release 110,880 pounds of propane. Company policy limits the maximum filling capacity of this tank to 88% at 60: F. It is assumed that the entire contents are released as a vapor w hich finds an ignition source, 10% of the released quantity is assumed to participate in the resulting explosion. The distance to the endpoint of a 1 psi overpressure for the worst case scenario is 0.40 miles. This distance extends beyond the facility boundary, encompasses several residences and industrial commercial business. Alternative Scenario: - A pull-away causing failure of a 25 foot length of 3 inch hose. The excess flow valves function to stop the flow. The contents of the hose are released. The vapor expands and upon finding an ignition source, it explodes. The 1 psi overpressure is expected to extend 106 feet. The distance to the endpoint of 1 psi for the alternative scenario is 106 feet. This distance extends beyond the facility boundary and encompasses an adjacent public rail road, but does not impact any public receptors. IV) The general accidental release prevention program and the specific prevention steps. This distribution facility complies with EPA's Acci dental Release Prevention Rule and with all applicable federal, state and local codes and regulations. This facility was designed and constructed in accordance with NFPA-58. All drivers have been thoroughly trained using NPGA's Certified Employee Training Program (CETP). V) Five-year accident history. There has been no accidental release or ignition of propane in the last five years. VI) The emergency response program. We have agreed to evacuate the facility employees in the event of a propane gas emergency. Therefore, no emergency response plan is required. However, for facilities with 11 or more employees, a written Emergency Action Plan and a Fire Prevention Plan must be implemented in accordance with OHSA 1910.38. For facilities with 10 or fewer employees the plans may be communicated orally and the employer need not maintain a written plan on site. For this facility, the owner has implemented an emergency response plan. VII) Planned changes to improve safety. It ap pears that all tanks were operational at this facility in 1995. The compressor for the rail car off loading was installed in the early 1990s. At our next available opportunity to do maintenance work, tank temperature gauges will be installed we will try and work to current NFPA 58 standards as needed. |