Riverside Plant - Executive Summary
LDEQ Facility ID 3302 |
Riverside Plant Risk Management Plan: Executive Summary
ACCIDENTAL RELEASE PREVENTION AND RESPONSE POLICIES
The TransCanada Gas Processing USA Inc. (TransCanada) Riverside 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 personnel and considering safety in the design, installation, operation, and maintenance of facility's processes. The TransCanada policy is to implement reasonable controls to prevent foreseeable releases of substances. However, if a release does occur, trained personnel will respond to, control, and contain the release.
DESCRIPTION OF THE STATIONARY SOURCE AND REGULATED SUBSTANCES
TransCanada owns and operates the Riverside Plant located in Ascension Parish, Louisiana. The Riverside Plant is a natural gas liquids fractionation plant capable of processing "raw make" which is the main feed. The plant separates ethane, propane,
n-butane, isobutane and natural gasoline from the main feed through a series of distillation columns. Natural gas is separated from the feed prior to fractionation.
The Riverside Plant was evaluated to determine if any regulated flammable or toxic substances exceeded the threshold quantity. Based on process knowledge, TransCanada identified the regulated substances and quantities kept on site. Listed flammable substances which are stored above threshold quantities at the Riverside Plant are natural gasoline, propane, isobutane, n-butane, raw make, used oil and heating oil. However, TransCanada has determined that used oil and heating oil have an National Fire Protection Association (NFPA) flammability hazard rating of 1 and natural gasoline has an NFPA flammability hazard rating of 3, which exempts these mixtures from threshold determination. Based on worst-case analysis, the distance to the endpoint exceeds the distance to public receptors. In addition, the Riverside Plant is
subject to OSHA PSM. Therefore, the Riverside Plant is classified as a Program 3 process under the ARP program.
OFFSITE CONSEQUENCE ANALYSIS RESULTS
Flammable Substances - Worst-Case Scenario
The endpoint for worst-case release of flammable substances is 1 psi overpressure (i.e., 15.7 psia), resulting from a vapor cloud explosion. The 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 explosion 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. Isobutane is the worst-case flammable release with a 1.02-mile distance to the endpoint.
Flammable Substances - Alternative-Case Scenario
A single alternative release scenario for all flammable substances is r
equired under the ARP program. A hypothetical, but likely to occur, release scenario has been identified for n-butane as follows. A 3-inch pipe on the truck rack is sheared during loading, causing the entire contents to empty from the truck. The n-butane will vaporize and may ignite in a vapor cloud explosion with an endpoint of 1 psi overpressure or a vapor cloud fire with an endpoint of the lower flammability limit (LFL) for n-butane. The alternative-case release of n-butane resulted in a 0.27-mile distance to the 1 psi overpressure endpoint and less than 0.06 mile distance to the LFL endpoint.
The Riverside Plant does not have any toxic substances held above the threshold quantity. Therefore, analysis of worst-case or alternative case release scenarios for toxic substances is not required.
GENERAL ACCIDENT RELEASE PROGRAM
The following is a summary of the of the accident prevention program in place at the Riverside Plant. Because the processes at the pl
ant that are regulated by the Environmental Protection Agency's (EPA's) risk management program (RMP) regulation 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 prevention program.
Active employee participation and involvement in the development and implementation of the Riverside Plant's PSM program is an important step toward achieving the objective to prevent or minimize the consequences of catastrophic releases of toxic, reactive, flammable, or explosive chemicals. Employee involvement will help to 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.
The Riverside Plant strongly promotes employee involveme
nt in safety issues through existing programs. These programs include a Health Safety & Environmental Team (which are made up of a cross section of employees and supervision), regularly scheduled safety meetings, tail-gate safety meetings, Hazard Communication, Safety Suggestion Forms, "near-miss" reporting, Behavioral Based Safety Programs and special training programs (emergency response training, first aid, etc.).
The Riverside Plant actively seeks employee involvement in the development and conducts all accident prevention activities through the appropriate existing safety programs. Accident prevention is discussed at the regularly scheduled safety meetings and/or during special training sessions if necessary. Employees are encouraged to discuss accident prevention with their supervisors if they have questions, comments, or suggestions.
Process Safety Information
Complete and accurate written process safety information concerning process chemicals, process technology, and
process equipment is essential to an effective PSM and RMP programs and to completing and maintaining a process hazard analysis (PHA). The process safety information 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. This information is readily available to all employees.
The Riverside Plant keeps a variety of technical documents that are used to help maintain safe operation of the processes. These documents address chemical properties and associated hazards, limits for key process parameters and specific chemical inventories, and equipment design basis/configuration information.
Chemical-specific information, including exposure hazards and emergency response/exposure treatment considerations, is provided in material safety data sheets (MSDS).
The gas plant also maintains numerous technical documents that provide info
rmation about the design and construction of process equipment. This information includes materials of construction, design pressure and temperature ratings, and electrical rating of equipment. 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.
Process Hazard Analysis (PHA)
The Riverside 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 Riverside Plant primarily uses the hazard and operability (HAZOP) and What-if/Checklist method analysis technique to perform these evaluations. 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 the team makes suggestions for additional prevention and/or 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 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, the plant pe
riodically 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 retained.
The Riverside Plant maintains written procedures that address various modes of process operations, such as; (1) startup, (2) normal operations, (3) temporary operations, (4) emergency shutdown, (5) normal shutdown, and (6) initial startup of a new process. Theses procedures provide guidance for experienced operators and also provide the basis for training new operators. Operating procedures are periodically reviewed and annually certified as current and accurate. The review and certification process involves both operators and technical sta
The intent of the operating 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 carrying out the stated procedures. The specific instructions include the applicable safety precautions and appropriate information on safety implications.
In addition to training on operating procedures the Riverside Plant has a comprehensive training program for all employees involved in operating the process. New employees receive basic training in gas plant operations. In addition, all operators periodically receive refresher training on the operating procedures to ensure that their skills and knowledge are maintained at ac
ceptable 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 that the operator understood the training.
The Riverside Plant uses contractors during periods of increased maintenance or construction activities. Because some contractors work on or near process equipment, the gas plant has procedures in place to ensure that contractors (1) perform their work in a safe manner, (2) have appropriate knowledge and skills, (3) are aware of the hazards of their workplace, (4) understand what they should do in the event of an emergency, (5) understand and follow site specific safety rules, and (6) inform gas plant personnel of any hazards that they find during there work. This is accomplished by providing contractors with an orientation session 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 beginning their work. In addition the Riverside Plant evaluates contractor safety programs and performance during the selection of a contractor. Gas plant personnel annually monitor contract performance to ensure that contractors are fulfilling their safety obligations.
Pre-startup Safety Review (PSSR)
The Riverside Plant conducts a PSSR on any new facility or facility modification that requires a change in 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 design specification and that all supporting systems are operationally ready. The PSSR involves field verification of the construction and serves a quality assurance function by requiring verification that accident prevention program requirements are pro
The Riverside Plant has well established practices and procedures for maintaining process equipment. The basic aspects of this program include (1) training, (2) developing written procedures, (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.
Another integral part of mechanical integrity program is quality assurance. The Riverside 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 materials and spare parts are used when repairs are made.
Safe Work Practices
The Riverside Plant 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 substances before process piping and equipment is opened, (4) a permit and procedure to control spark-producing activities (i.e., hot work), and (5) a permit and procedure to ensure that adequate precautions are in place before entry into a confined space. These procedures (and others), along with training of affected personnel, form a system to help ensure that operations and maintenance activities are performed safely.
Management of Change
The Riverside Plant has a comprehensive system to manage changes to all covered processes. This system
requires that changes to items such as process equipment, 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 Riverside Plant 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 gather the facts, determine the root cause, and develop corrective action to pre
vent the reoccurrence of the incident or a similar incident. The investigation team documents its findings, develops recommendation to prevent a recurrence, and forwards these results to the business management team for resolution.
To help ensure that the accident prevention program is functioning properly, the Riverside Plant periodically conducts an audit to determine whether the procedures and practices required by the accident prevention program are being implemented. PSM compliance audits are conducted at least every 3 years. Safety audits are conducted annually. Both hourly and staff 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.
CHEMICAL SPECIFIC PREVENTION STEPS
The processes at the Riverside 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 Riverside 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 Riverside 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:
1. Hydrocarbon detectors with alarms.
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, backup firewater pump)
6. Atmospheric relief devices.
1. Fire suppression and extinguishing systems
2. Trained personnel in emergency procedures
3. Personal protective equipment (e.g., chemical protective clothing, face shields)
FIVE YEAR ACCIDENT HISTORY
The Riverside Plant has an excellent record of accident prevention. Over the past 5 years there have been no accidental releases.
EMERGENCY RESPONSE PROGRAM INFORMATION
The Riverside Plant 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 release occurs, and post-incident cleanup and decontamination requirements. In addition, the plant 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 annual training in the procedures that relate to their specific emergency response duties. The emergency response program is updated when necessary based on modifications made to Riverside Plant facilities. The emergency response program changes are administered through the Management of Change (MOC) proces
s, which includes informing and/or training affected personnel in the changes.
The overall emergency response program for the Riverside Plant is coordinated with the Ascension Parish, Louisiana, Local Emergency Planning Committee (LEPC) and Gonzales Area Mutual-Aid Association (GAMA). This coordination includes periodic meetings of the committee, which includes local emergency response officials, local government officials, and industry representatives. The Riverside 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 Riverside Plant conducts periodic emergency drills that involve the LEPC and emergency response organizations, and the gas plant provides annual refresher training to local emergency responders regarding
the hazards of regulated substances in the plant.