Shell Chemical Company (Mobile Site) - Executive Summary
Risk Management Plan Executive Summary |
ACCIDENTAL RELEASE PREVENTION AND RESPONSE POLICIES
Shell Chemical Company and Shell Chemical's Mobile Site are part of the Royal Dutch/Shell Group of Companies. Throughout Shell we are committed to pursuing the goal of no harm to people and to protecting the environment as part of our overall Health, Safety, and Environment (HSE) commitments. We take a systemic approach to HSE management and strive for continuous improvement. At Shell's Mobile Site, our goal is the prevention of accidents and releases. Programs to achieve this include training for personnel, complying with industry and company standards for safety in materials in design and operation, conducting periodic hazards analyses of processes, evaluating the possible safety and environmental effects of changes before they are implemented, properly and pro-actively maintaining equipment assets, performing routine inspection of equipment, etc. If an accident or release does occur, it
is investigated to determine the cause(s) and to finds way to prevent recurrence. Plant personnel are also trained to respond to control or contain a release, should one occur, and to minimize its impact.
STATIONARY SOURCE AND REGULATED SUBSTANCES
The Mobile Site is located approximately 13 miles north of Mobile, Alabama. The facility includes a variety of processes for refining crude oil into petroleum products and chemical feedstocks. Products from the facility include gasoline, diesel fuel, aviation fuel, propane, butane, and "olefin feed" - a chemical feedstock used elsewhere for the production of other chemical products. The plant has four regulated flammables including propane, butane, isobutane and isopentane.
WORST CASE RELEASE AND ALTERNATE RELEASE SCENARIOS
The worst case scenario (WCS) associated with a release of flammable substances at the Mobile Site is a vapor cloud explosion (VCE) involving the full inventory of the largest storage tank containing normal butane.
No credit is taken for administrative controls to limit the storage inventory in the tank; therefore in modeling the WCS is assumed to release, completely vaporize, and ignite, resulting in a VCE. The maximum distance to the 1-psi endpoint for this WCS reaches an offsite public receptor. Although there are controls to prevent such releases and to manage their consequences, no credit for passive mitigation measures was taken into account in evaluating this WCS, consistent with the requirements of the RMP guidelines. The alternate release scenario (ARS) for flammable substances at the Mobile Site is a VCE resulting from the release of butane from a gasket leak. The release is expected to be isolated by the operators within 10 minutes (active mitigation). The maximum distance to the 1-psi endpoint for this event does not reach offsite receptors. The plant does not produce or store regulated toxic materials above the threshold quantity limit, thus no toxic WCS or ARS are addresse
d in this executive summary and RMP Plan.
GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM STEPS
The following is a summary of the general accident prevention program in place at the Mobile Site. Because processes at the facility 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.
Process Safety Information
The Mobile Site 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. Specific departments within the facility are assigned responsibility for maintaining up-to-date process safety information. Chemical-specific information, including exposure hazards a
nd emergency response/exposure treatment consideration, is provided in material safety data sheets (MSDSs). This information is supplemented by documents that specifically address known corrosion concerns and any known hazards associated with the inadvertent mixing of chemicals. For specific process areas, the facility has documented safety-related limits for specific process parameters (e.g., temperature, level, composition). The Mobile Site ensures that the process is maintained within these limits using process
controls and monitoring instruments, trained personnel, and protective instrument systems (including shutdown systems). The facility also maintains numerous technical documents that provide information about the design and construction of process equipment to include, but not limited to materials of construction, design pressure and temperature ratings, and electrical rating of equipment. This information, in combination with written procedures and trained personnel, pr
ovides a basis for establishing inspection and maintenance activities, as well as for evaluation proposed process and facility changes to ensure that safety features in the process are not compromised.
Process Hazard Analysis
The Mobile Site has a comprehensive program to help ensure that hazards associated with the various processes are identified and controlled. Within this program, each covered process is systematically examined to identify hazards and ensure that adequate controls are in place to manage these hazards. The Mobile Site 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 contribute 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 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, the facility 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 oper
ating. The results and findings from these updates are documented and retained. Team findings are forwarded to management for consideration and the final resolution of the findings is documented and retained.
The Mobile Site 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 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.
To implement the written procedures for process operations, the Mobile Site has implemented a comprehensive training program for all employees involved in operating a process. New employees receive basic training in process unit 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, skill 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.
The Mobile Site 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 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 eequipment functions as intended, and to verify that equipment is within acceptable limits (e.g., adequate wall thickness for pressure vessels, control instruments operating properly). If a deficiency is identified, employees will correct the deficiency, take the equipment out or service for repair, or an Managemen
t Of Change (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. The Mobile Site incorporates quality assurance measures into equipment purchases and repairs. This helps ensure that new equipment is suitable for its intended use and proper materials and spare parts are used when repairs are made.
Management of Change (MOC)
The Mobile Site 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 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.
Pre-startup Safety Reviews (PSSRs)
The Mobile Site conducts a PSSR for any new process or process modification that requires a change in the process safety information. The purpose of the PSSR is to ensure 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 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. PSSR's are also conducted following major maintenance or unit shutdowns to verify the safety and integrity of the equipment prior to restart.
To help ensure that the accident prevention program is functioning properly, the Mobile Site periodically conducts audits 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 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 Mobile Site promptly investigates all incidents that resulted in, or reasonable
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 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. The final resolution of each finding or recommendation is documented, and the investigation results are reviewed will 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.
Safe Work Practices
The Mobile Site has long-standing safe work practices in place to h
elp 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 source for equipment undergoing maintenance; (3) a procedure for safe removal of hazardous materials before process piping or equipment is opened; (4) a permit and a 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, along with training of affected personnel, form a system to help ensure that operations and maintenance activities are performed safely.
The Mobile Site uses contractors to supplement its workforce and during periods of increased maintenance or construction activities. Because some contractors work on or near process equipment, the facility has procedures in place to ensure that contractors (1) perform their wo
rk 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 Mobile Site evaluates contractor safety programs and performance during the selection of a contractor. Facility personnel periodically monitor contractor performance to ensure that
contractors are fulfilling their safety obligations.
The Mobile Site encourages employees to participate in all facets of process safety management and accident prevention. Examples of employee participation range from upda
ting and compiling technical document 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 facility accident 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 facility and addresses each accident prevention program element. In addition, the facility has a number of initiatives under way that address process safety and employee safety issues. These initiatives include forming teams to promote both process and personal safety. The teams typically have members from various areas of the plant, including operations, maintenance, engineering, and plant management.
CHEMICAL SPECIFIC PREVENTION STEPS
The processes at the Mobile Site have hazards that must be managed to ensure continued safe operation. The accident prevention program summarized previously is applied to al
l RMP-covered processes at the facility. 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, the facility 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 various processes:
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 temperature)
5. Curbing or diking to contain liquid releases
6. Redundant equipment and instrumentation (e.g. uninterruptible power supply for process control system, backu
p firewater pump)
1. Fire suppression and extinguishing systems
2. Deluge system for specific equipment
3. Trained emergency response team
4. Personal protective equipment (e.g. protective clothing, self-contained breathing apparatus)
FIVE-YEAR ACCIDENT HISTORY
The Mobile Site has had no RMP accidents recorded over the last five years.
EMERGENCY RESPONSE PROGRAM
The Mobile Site 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 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 incident command, 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 Mobile Site has procedures that address maintenance, inspection, and testing 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 the processes or other facility areas. 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 the Mobile Site is coordinated with the Mobile County, Local Emergency Planning Committee (LEPC). This coordination includes periodic meetings of the committee, which includes local emergency response officials, local government officials, and industry representatives. The Mobile Site 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.
PLANNED CHANGES TO IMPROVE SAFETY
The Mobile Site resolves all findings from PHAs, some of which result in modifications to the process. The following types of changes are planned:
o Upgrade shutdown and clearing procedures for LPG storage tanks
o Install remote shutdown capability for LPG product pumps in the LPG storage area
o Conduct training on modifications and upgrades to the LPG storage and loading areas