Emigrant Trail Gas Plant - Executive Summary

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Risk Management Plan 
 
 
                  Duke Energy Field Services 
 
                   Emigrant Trail Gas Plant 
 
                    Rock Springs, Wyoming 
 
Executive Summary 
 
Accidental Release Prevention and Response Policies 
 
The Emigrant Trail Gas 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 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.  We also work closely with our public emergency responders 
providing them with training and equipment so that  they can respond safet 
y and 
efficiently to emergencies that might occur at our facility. 
 
Description of the Stationary Source and Regulated Substances  
 
The Emigrant Trail Gas Plant, located 46 miles west of Rock Springs, WY off I-80, 
operates a variety of processes to produce petroleum products (e.g., natural gas, 
propane, butane, condensate) from oil and gas wells.  The Emigrant Trail Gas Plant 
handles methane, ethane, propane and butane which are regulated flammables. It 
processes approximately 72 million cubic feet a day of raw natural gas and natural gas 
liquids.  The Emigrant Trail Gas Plant does not use, process or store a reportable 
quantity of toxic regulated substances. 
 
Hazard Assessment Results 
 
The Worst Case Scenario (WCS) associated with a release of flammable materials in 
processes at the gas plant is a vapor cloud (VCE) involving the full inventory of the 
largest process vessel containing 274,560 pounds of a propane, ethane mix. The 
maximum distance to the 1-psi endpoint for this WCS is 0. 
54 miles.  No passive 
mitigation measures were taken into account in evaluating this WCS. 
 
Five-Year Accident History 
 
Within the past five years the processes have had no accidental release that caused 
offsite impacts provided in the risk management program rule (40 CFR 68.10(b)(1)). 
 
 
 
 
 
 
 
 
General Accidental Release Prevention Program/Chemical-Specific 
Prevention Steps 
 
The following is a summary of the accident prevention program in place at the Emigrant 
Trail Gas Plant.  Because processes at the Emigrant Trail Gas Plant that are regulated 
by the EPA Risk Management Program (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. 
 
Employee Participation  
 
The Emigrant Trail Gas Plant provides for and encourages employees to participate in 
all facets of process safety management and accident prevention.  Exampl 
es 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 Emigrant Trail 
Gas Plant accident prevention 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 Emigrant Trail Gas Plant and addresses each accident 
prevention program element.  In addition, The Emigrant Trail Gas Plant has a number 
of initiatives under way that address process safety and employee safety issues.  
These initiatives include a safety committee to promote both process and personal 
safety.  The committee typically has members from various areas of the plant, including 
operations, maintenance, and local plant management. 
 
Process Safety Information 
 
The Emigrant Trail Gas 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.  Specific 
employees within the Emigrant Trail Gas Plant are assigned responsibility for 
maintaining up-to-date process safety information.  This information is 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 considerations, is provided in material safety data sheets.  
This information specifically addresses known corrosion concerns and any known 
hazards associated with the inadvertent mixing of chemicals.  For specific process 
areas, the Emigrant Trail Gas Plant has documented safety-related limits for specific 
process parameters (e.g., temperature, level,  
composition).  The Emigrant Trail Gas 
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 Emigrant Trail Gas 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 features in the process are not compromised. 
 
Process Hazard Analysis (PHA)   
 
The Emigrant Trail Gas Plant has a comprehensive program to help ensure that 
hazards associated with the various processes are identified and co 
ntrolled.  Within 
this program, each process is systematically examined to identify hazards and ensure 
that adequate controls are in place to manage these hazards. 
 
The Emigrant Trail Gas Plant primarily uses the What If / Checklist (DP-10) analysis 
technique to perform these evaluations.  This 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, 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 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 Emigrant Trail Gas 
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 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 finds is documented and 
retained. 
 
 
 
Operating Procedures 
 
The Emigrant Trail 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 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. 
 
Training 
 
To complement the written procedures for process operations, the Emigrant Trail Gas 
Plant has implemented a comprehensive training program for all employees involved in 
operating a process.  New employees receive initial training in Emigrant Trail Gas Plant 
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., tests, sk 
ill 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 that the operator understood the training. 
 
Contractors 
 
The Emigrant Trail 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 Emigrant Trail Gas 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 em 
ergency, (5) understand and 
follow site safety rules, and (6) inform gas 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, the Emigrant Trail Gas Plant evaluates contractor safety programs and 
performance during the selection of a contractor.  Emigrant Trail Gas Plant personnel 
periodically monitor contractor performance to ensure that contractors are fulfilling their 
safety obligations. 
 
 
 
Pre-startup Reviews 
 
The Emigrant Trail Gas Plant conducts a pre-startup safety review (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 plac 
ing 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 read.  A PSSR involves field verification of the construction and serves a 
quality assurance  function by requiring verification that accident prevention program 
requirements were properly implemented. 
 
Mechanical Integrity 
 
The Emigrant Trail Gas Plant 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. 
 
Mai 
ntenance 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).  If a deficiency is 
identified, employees will correct the deficiency before placing the equipment back into 
service (if possible), or a group of experts 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 
Emigrant Trail Gas Plant incorporates quality assurance measures int 
o 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.  Pre-startup safety reviews are also used to support the quality assurance 
program. 
 
Safe Work Practices 
 
The Emigrant Trail Gas 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 that is being worked on, (3) a procedure 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 en 
sure operations and maintenance activities are 
performed safely. 
 
Management of Change 
 
The Emigrant Trail Gas Plant has a comprehensive system to manage changes that 
affect any 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. 
 
Incident Investigation 
 
The Emigrant Trail Gas Plant promptly investigates all incidents that resulted in, or 
reasonably could have 
resulted in, a fire/explosion, 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 Emigrant Trail 
Gas Plant management for resolution.  Corrective actions taken in response to the 
investigation team's findings and recommendations are tracked until they are 
completed.  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. 
 
Compliance Audits 
 
To help ensure that the accident prevention program is functioning properly, the 
 
Emigrant Trail 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.  Personnel from 
other gas plants compose the Audit Team.  Both hourly and staff personnel participate 
as audit team members.  The audit team develops findings that are forwarded to 
Emigrant Trail Gas Plant management for resolution.  Corrective actions taken in 
response to the audit team's findings are traced until they are completed.  The final 
resolution of each finding is documented, and the two most recent audit reports are 
retained. 
 
Summary of Process Hazards, Safety Features, and Hazard Analysis 
Findings 
 
The processes at the Emigrant Trail Gas Plant have hazards that must be managed to 
ensure continued safe operations. 
 
 Universal Prevention Activities 
 
 The accident prevention program summarized previously is applied to all EPA RMP  
 covered proce 
sses at the Emigrant Trail Gas Plant.  Collectively, these prevention 
 program activities help prevent potential accident scenarios that could be caused by 
 (1) equipment failures and (2) human errors. 
 
 Specialized Safety Features 
 
 The Emigrant Trail 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 in all closed compressor buildings 
 
 Release Containment/Control 
 
    1. Process relief valves that discharge to a vent system to handle episodic  
       releases 
 
    2. Valves to permit isolation of the process (manual or automated) 
 
    3. Automated shutdown systems for specific process parameter (e.g., high 
       level, 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. Trained emergency first-responder personnel 
 
    3. Personal protective equipment  
 
    4. Spacing of equipment in accordance with IRI spacing guideline.   
 
    5. Emergency shutdowns strategically placed around the plant, that 
       automatically shuts in the inlet and outlet and blows the plant down through 
       the vent system. 
 
Emergency Response Program 
 
The gas 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 procedures.  In 
addition the Emigrant Trail Gas 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 training in 
these procedures as necessary to perform their specific emergency response duties.  
The emergency response program is updated as necessary.  Any significant changes 
to the emergency response program 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 Emigrant Trail Gas Plant is 
coordinated with the Uinta Fire Department and the local emergency plan 
ning 
committee (LEPC).  This coordination includes periodic meetings with the LEPC, which 
includes local emergency response officials, local government officials, and industry 
representatives.  The 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 gas  plant conducts periodic emergency drills.  
 
Planned Changes to Improve Safety 
 
Although Emigrant Trail Gas Plant management does not believe additional safety 
measures are necessary to prevent offsite impacts from accident releases, it does 
resolve all findings from the Process Hazards Analysis and the Compliance Audits.  
Some of these findings result in modifications to the process.  The following types of 
changes were implemented in response to PHA findings and th 
e Compliance Audits: 
 
 1. Revision to personnel training programs. 
 2. Revision to operating procedures. 
 3. Revision to inspection procedures. 
 4. Modifications to the process instrumentation and control loops. 
 5. Updates to the Process Safety Information. (P&ID's)
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