Phillips 66 Woods Cross Refinery - Executive Summary
PHILLIPS 66 COMPANY |
WOODS CROSS REFINERY
RISK MANAGEMENT PLAN
GENERAL DESCRIPTION OF FACILITY
The Phillips 66 Woods Cross Refinery is located approximately 10 miles north of Salt Lake City, Utah. The primary function of the refinery is to convert various crude oils into marketable products, including various grades of gasoline, diesel, jet fuel, propane and asphalt. This facility has a rated processing capacity of 25,000 barrels a day of crude oil. The refinery has been owned and operated by Phillips since 1947, when it purchased it from Wasatch Oil and Refining Company. Over the past 50 years, Phillips has made extensive additions and im
provements to the refinery, including numerous safety and environmentally related processes.
There are several RMP regulated chemicals at the refinery produced as either process intermediates or finished products. Flammable substances are generally mixtures of gases/gas liquids such as methane, ethane, propane, butane, isobutane and pentane. The only regulated toxic chemical onsite above the RQ is Hydrofluoric (HF) Acid. While flammable mixtures can be found in most refining processes, HF Acid is only present in alkylation unit.
HAZARD ASSESSMENT & MITIGATION MEASURES
The worst-case scenario (WCS) associated with toxic substances is a catastrophic release of HF Acid (74,200 lbs) from the alkylation settler/cooler vessels. This maximum quantity was derived from an engineering review of the process. Although there are numerous controls to prevent such releases and to manage their consequences, no credit for either active or passive mitigation was taken in
to account in evaluating this scenario. The maximum distance to the toxic endpoint for HF Acid (0.016 mg/l) for this WCS is 11 miles (calculated using EPA's OCA Guidance Reference Equations).
The alternate-case scenario (ACS) associated with toxic substances is a piping leak (0.2" diameter) of HF Acid in the same process area listed for the WCS. Under the ACS, approximately 27 lbs of HF Acid is released over a period of 12 minutes. Credit for both passive and active mitigation was taken into account in evaluating this scenario, including water spray/deluge systems, rapid acid transfer system, ReVap process, audible alarms/operator intervention, etc. The maximum distance to the toxic endpoint for HF Acid (0.016 mg/l) for this ACS is .06 miles (calculated using EPA's OCA Guidance Reference Equations). It should be noted that the ACS does not result in an offsite impact.
The WCS associated with flammable substances is a vapor cloud explosion (VCE) involving 1,045,800 lbs of natura
l gas liquids (i.e., propane, butane, isobutane, pentane) from a storage sphere in the West Tank Farm. This maximum quantity was derived by calculating the volume of the largest pressurized storage vessel containing a Liquid Petroleum Gas (LPG). This WCS assumes the entire inventory of this vessel is released, vaporizes and ignites, resulting in a vapor cloud explosion. Although there are several controls to prevent such releases and to manage their consequences, no credit for mitigation was taken into account in evaluating this scenario. The maximum distance to the 1 psi endpoint for this WCS is 0.82 miles (calculated using EPA's OCA Guidance Reference Equations). It should be noted that previous quantitative risk studies performed for Phillips did not indicate that a VCE would occur in this case; nevertheless, EPA guidance requires the company to assume that a VCE would occur for the purposes of RMP.
The ACS associated with flammable substances is a VCE or flash fire involving
a release of butane caused by a hose leak during railcar loading in the East Tank Farm. Under the ACS, approximately 11,200 lbs of butane are released over a 10 minute period. Credit for passive and active mitigation was taken into account in evaluating this scenario, including combustible gas detectors, high flow shutoff valves, fire water monitors and operator intervention. The maximum distance to the 1 psi (or lower flammable level) endpoint for this ACS is 0.06 miles (calculated using EPA's OCA Guidance Reference Equations). It should be noted that the only public area affected by the ACS is the roadway between the railcar loading spur and the processing units.
GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM
The following is a summary of the general accident prevention programs in place at the Phillips 66 Woods Cross Refinery. Since this facility is subject to the OSHA Process Safety Management (PSM) standard (promulgated in 1992), these program elements have been in place fo
r several years, which essentially mirror the prevention program requirements of EPA's RMP standard.
Process Safety Information (PSI)
The Phillips 66 Woods Cross Refinery maintains a variety of technical documents that are used to maintain safe operation of the processes. Written PSI provides employees with a baseline of information to identify hazards of the chemicals used or produced in the process, information about the technology of the process, and information about the equipment in the process. This process information provides a foundation for performing the unit Process Hazards Analysis, developing operating procedures and determining applicability, in some cases, for the need for management of change.
Process Hazard Analysis (PHA)
A process hazards analysis is a systematic and methodical study to identify and analyze the significance of potential hazards associated with the processing and handling of highly hazardous chemicals. A PHA provides information to Refinery man
agement and employees in making decisions for improving the safety and reducing the consequences of undesirable and/or unplanned releases of highly hazardous chemicals.
The HAZOP (Hazard and Operability Study Technique) methodology was used for performing all PHA's at the Phillips 66 Woods Cross Refinery. Each unit process is divided into small sections, referred to as "nodes". Each node is studied using a series of guide words representing deviations from normal operations (e.g., no flow, reverse flow, more flow, less flow). The causes for each deviation are recorded and considered for potential effects. Existing safeguards are noted, then suggestions to prevent the deviation, or mitigate its effects, are recorded for all findings that result in significant hazards. The findings from the HAZOP, which are reviewed by refinery management for final acceptance and assignment, are further divided into one of the following two categories:
- Recommendations are items which the PHA tea
m believes have catastrophic implications.
- Advisories are items which the team believes could prevent equipment damage, product loss or unit shutdown, but would not contribute to a catastrophic failure.
Written operating procedures provide instructions for safely and consistently conducting activities involved in the operations of a process unit. Copies of the Operating Procedures manuals are available to employees at all control rooms, as well as various office locations. Written procedures address various operating modes, such as 1) unit startup, 2) normal operations, 3) temporary operations, 4) emergency shutdown, 5) normal shutdown, and 6) consequences of deviation. Operating Procedures manuals have been developed for all operating units at the Woods Cross Refinery, regardless of whether or not they are considered to be a covered process under PSM; they complement the existing "Operating Manuals", which are more detailed in nature.
To complement the written procedures for process operations, the Phillips 66 Woods Cross Refinery has implemented a comprehensive training program for all employees involved in operating a process. Training modules developed for each operating unit primarily cover operating procedures, which include such topics as startup/shutdown, emergency procedures, safety precautions, etc. Written and practical tests are give to all participants after the training modules have been completed. Refresher training/certification is provided every three years to operations personnel on the operating units for which they are responsible. Training in safe work practices is given to all employees during new employee safety orientation, annual safety training sessions, special classes and monthly safety meetings.
The intent of the mechanical integrity program is to provide a management system that promotes the long-term reliability of the Refinery processes and related equipm
ent. The mechanical integrity program applies to the following types of equipment:
- Pressure vessels and storage tanks
- Piping systems and components
- Relief and vent systems
- Emergency shutdown systems
The basic aspects of the mechanical integrity system include: 1) conducting training for craftsmen/technical personnel, 2) developing written maintenance and inspection procedures, 3) performing inspections and tests, 4) correcting identified deficiencies, and 5) applying quality assurance measures. All critical equipment (listed under the six general types above) are inspected and maintained on a regular schedule. Deficiencies are corrected under the plant work order system.
Management of Change (MOC)
Management of Change procedures require that proposed changes are reviewed before they are implemented to ensure that all safety-related concerns and issues are considered and appropriate action is taken. MOC procedures apply to any temporary or permanent cha
nge (except for "replacement in kind") to process chemicals, technology, equipment or procedures that affect a covered process; this also includes changes to the general plant or facility that affect a covered process or impact offsite (i.e., "public") receptors.
Pre-startup safety review (PSSR)
Pre-startup safety reviews are performed to ensure that the appropriate process safety information requirements have been met, any new or modified equipment has been installed according to design specifications, appropriate safety and operating procedures are in place and applicable training has been given prior to start-up of new or modified facilities. A PSSR is conducted for all installations or modifications that require an MOC procedure.
Audits serve as a self-evaluation tool to measure compliance with the PSM standard and the effectiveness of the Company's implementation program. A PSM compliance audit is performed at the Phillips 66 Woods Cross Refinery at least
every three years. The audit team consists of a variety of multi-disciplined employees who utilize a set of self-audit checklists based on the OSHA PSM Standard. All audit findings and responses are entered into a computer database for tracking purposes. Results of this audit are also reported each year to the President of the Company as part of an annual letter of compliance certification.
Prompt investigation of injuries, incidents and near misses is done to determine the root cause(s) of such events and prevent reoccurrences. A formal investigation will be made for all incidents which result in, or could have reasonably resulted in any of the following:
- Catastrophic release of highly hazardous chemicals,
- Recordable injury,
- Spill or release which would require reporting to Federal environmental authorities,
- Significant (>$100k) property loss or business interruption,
- Any other incident deemed appropriate by management.
All incident investigati
on reports are entered into a computer database for tracking purposes. Incident investigation reports are retained onsite for at least 5 years so that they can be reviewed during future PHA revalidations and/or included in RMP updates.
The intent of employee participation is to ensure that Phillips employees are involved in all key aspects in the development and implementation of risk management plans and related issues. Employees have access to all information developed to comply with the PSM standard. Examples of employee participation range from updating and compiling technical documents to participating as a member of a PHA team. The facility also has an employee-driven behavior modification system known as "SPIDER" (Safe Performance Initiative Directly Eliminating Risk). This process is used to reduce "at-risk" behaviors, resulting in fewer unsafe acts and conditions.
Safe Work Practices
Phillips has several long-standing safe work practices that pr
omote process safety. Examples of these include 1) hot work permits to control work that may produce a flame, arc or spark in plant areas where flammable materials may be present, 2) confined space entry permits to ensure adequate safety precautions have been taken prior to entering vessels, tanks and other confined spaces, 3) excavation permits to ensure all underground lines and utilities have been identified prior to digging and that shoring/sloping systems have been employed to protect workers from cave-ins and other forseeable hazards, 4) lockout/tagout procedures to ensure isolation of energy sources prior to working on equipment, and 5) pressure-relief device permits to ensure that adequate, alternate relief paths are available in the process prior to removal of any such devices. These procedures, along with others, form a system to help ensure that operations and maintenance activities are performed in a safe manner.
Contract employees at the Phillips 66 Woods
Cross Refinery provide labor for general construction, turnaround work and various service-related jobs. While contractors are not involved in plant operations, their actions may have an influence on process safety. Phillips informs contractors of fire, explosion and toxic release hazards as well as its emergency response plan during site safety orientation, which all contractors are required to attend prior to working at this facility. In addition, contractors involved in maintaining the on-going integrity of process equipment receive "Process Overview Training". The contract employer will ensure that their employees are trained in (and follow) the work practices necessary to safely perform their job, including those specific to the Woods Cross Refinery. This may be accomplished through the use of periodic self-audits, safety meetings, training sessions, etc. Phillips will also note compliance with safe work practices during its periodic audits of the contract employees.
AR ACCIDENT HISTORY
Over the past 5 years there have not been any releases of RMP listed chemicals resulting in significant offsite impacts. Every incident is investigated to determine its root cause and methods to prevent reoccurrence.
EMERGENCY RESPONSE PROGRAM
The Phillips 66 Woods Cross Refinery maintains a written emergency response program, which is in place to protect worker and public safety as well as the environment. The program consists of procedures for responding to various emergencies, including chemical releases, fires and explosions. There are four emergency response teams maintained at the refinery, which consist of volunteer employees: 1) Fire Brigade, 2) Hazmat Team, 3) Technical Rescue Team, and 4) Emergency First Responders (medical first aid). All team members receive initial and periodic refresher training. The Incident Command System (ICS) is used to manage all emergency response situations. The refinery is staffed by a shift superintendent on a 24 hou
rs/day basis, who is the acting Incident Commander until relieved by one of the primary Incident Commanders. Emergency communication systems are maintained to notify refinery team members and the local emergency dispatcher, as well as coordinate response efforts. Communication systems include audible plant alarms, two-way radios, pagers and mobile phones.
Phillips is a member of the Salt Lake Refiners Mutual Aid organization, which allows each company to borrow resources, such as fire fighting apparatus and foam, during an emergency. The refinery emergency response teams periodically conduct drills and training exercises with members of the Mutual Aid organization as well as local Fire Departments.
Phillips sponsors a CAER (Community Awareness and Emergency Response) Committee, which is comprised of local officials and fire, police and sheriff representatives. The CAER Committee meets bi-monthly to discuss citizen concerns about the refinery, emergency response efforts and othe
r common, community issues. The LEPC (Local Emergency Planning Committee) chairman is a member of the Phillips CAER Committee.
PLANNED CHANGES TO IMPROVE SAFETY
The Phillips 66 Woods Cross Refinery has implemented numerous safety improvements over the past decade. Many of these changes were prompted by the OSHA Process Safety Management Standard (PSM), which required very detailed hazard assessment studies; one specific example was to commission a comprehensive study of all pressure safety valves and flare headers to ensure their mechanical integrity during normal and upset operations. Other improvements are the result of Company policies and standards, such as the installation of a new, centralized control room outside of the processing area.
Phillips' Process for Safety and Environmental Excellence (PSEE) system is used to set both short-term and long-term goals and objectives at each business unit throughout the Company. The Woods Cross Refinery develops annual safety and en
vironmental improvement objectives as part of its business planning and budgeting cycle. Some of the planned objectives are:
- Increase employee and contractor participation in the facility's behavior modification safety program, which increases general safety awareness, thus reducing the potential for accidents that could affect both onsite workers and area residents.
- Conduct an audit of all health, environmental and safety systems to ensure compliance with both governmental and Company policies and standards.
- Replace/upgrade several electrical motor control centers (MCC) in the plant, which results in improved mechanical and operational integrity.
- Continue implementation of the Company's Team Perfected Manufacturing (TPM) program, which results in improved mechanical and operational integrity.
- Continue with the planned inspection of plant safety valves, vessels, tanks and process piping, which results in improved mechanical and operational integrity.
- Implement a new
preventive maintenance program for fire water deluge systems, which results in improved reliability of these mitigation systems.
- Conduct emergency response drills and exercises with mutual aid organizations and local fire departments.