Colorado Interstate Gas Co. Natural Buttes Station - Executive Summary

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At Natural Buttes Station we are committed to operating in a manner that is safe for our workers, the public, and the environment.  As part of this commitment, we have established a system to help ensure safe operation of the processes at this facility.  One component of this system is a risk management program (RMP) that helps manage the risks at this facility and that complies with the requirements of the Environmental Protection Agency's (EPA's) regulation 40 CFR part 68, Accidental Release Prevention Requirements: Risk Management Programs (the RMP rule). 
 
The RM program at this facility consists of three (3) elements:   
1) A hazard assessment to help understand: 
   The potential offsite consequences of hypothetical accidental releases, and 
   Accidents that have occurred during the last five (5) years associated with the use of  
   substances regulated by the RMP rule (regulated substances).   
2) A prevention program to help maintain and safely operate the processes containing 
more than a  
    threshold quantity of a regulated substance (covered processes). 
3) An emergency response program to help respond to accidental releases of regulated substances from  
    covered processes. 
 
This facility has a comprehensive safety program in place establishing many levels of safeguards or controls against release of a hazardous substance and injuries and damage to its employees, the public, and the environment. We limit the use of hazardous substances.  Before using a hazardous substance, less hazardous alternatives are considered.  When a hazardous substance is used, consideration is given to the potential for this substance to adversely affect our workers, the public, and the environment, and we take steps to prevent any such effects. 
 
The safety program consists of a number of elements, only some of which are required by the RMP rule.  There are other prevention progra 
ms which are company specific and those required by the Department of Transportation under parts 192 or 195 and OSHA under the PSM regulation. This RMPlan is primarily intended to describe those parts of the safety program at this facility that are required by the RMP rule. 
 
 
ACCIDENTAL RELEASE 
We are committed to the safety of workers and the public, and the preservation of the environment, through the prevention of accidental releases of hazardous substances.  This facility implements reasonable prevention programs to prevent foreseeable releases of hazardous substances.  These controls include training programs for personnel; programs to help ensure safety in the design, installation, operation, and maintenance of processes; and programs to evaluate the hazards at this facility. 
 
In the event of an accidental release, we control and contain the release in a manner that will be safe for workers and will help prevent injury to the public or the environment.  This facility coordinates 
response efforts with the local emergency response personnel. 
 
 
REGULATED SUBSTANCES 
This facility is primarily involved in the recovery of liquid hydrocarbons from a gas stream.  As part of this process, we handle several regulated, flammable substances in sufficient quantities to be covered by the RMP rule.  There are no such quantities of regulated toxic substances handled at the Plant.  The following RMP-regulated flammables are found at the Plant: 
Ethane 
Methane 
Propane 
Iso-Butane 
Butane 
Iso-Pentane 
Pentane 
 
 
OFFSITE CONSEQUENCE ANALYSIS 
An offsite consequence analysis was performed to estimate the potential for an accidental release of a regulated substance to affect the public or the environment.  The offsite consequence analysis consists of evaluating both worst-case release scenarios and alternate release scenarios.  We do not expect a worst-case release scenario to ever occur.  The alternate release scenarios were selected to help the local fire department or, if applicable, 
 emergency planning committee improve the community emergency response plan.  An alternate release scenario represents a release that:  
1) might occur at this facility 
2) would result in the greatest potential offsite consequences if the release occurred. 
 
The main objective of performing the offsite consequence analysis is to determine the distance at which certain effects might occur to the public because of an accidental release (called the endpoint distance).    At distances less than the endpoint distance, the effects could be greater; at distances greater than the endpoint distance, the effects would be less. 
 
The Worst-Case release Scenario (WCS) for flammable substances is failure of the Condensate Storage Tanks (V-13 or V-14), resulting in a vapor cloud explosion.  Each tank can contain up to 280,000 lbs. of Natural Gas Liquids (NGL). No administrative controls or passive mitigation were considered for this release scenario although procedures do exist which usually limit the 
filling of the vessels.  The maximum distance to the overpressure endpoint is 0.52 miles.  Few public receptors are located within this distance. 
 
The Alternate Release Scenario (ARS) for flammable substances is a hose rupture at the NGL loading station while loading a truck with natural gas liquids. This scenario assumes that the flammable substances (ethane, propane, butane, pentane, and condensate) are released through the ruptured hose for 2 minutes before workers detect the release, initiate the pump shutdown and isolation of the piping section.  The substances form a pool, which ignites and results in a pool fire. Using the methods in the EPA's Offsite Consequence Analysis Guidance, the predicted distance to the flammable endpoint is 0.05 miles. There are no residents, public receptors, or environmental receptors within this distance.  
 
 
PREVENTION PROGRAM 
This facility uses a prevention program to help prevent accidental releases of hazardous substances.  Beginning in 1994, thi 
s prevention program for processing of natural gas was formalized to comply with the 14 elements of the OSHA process safety management (PSM) prevention program.  In 1996, the EPA RMP rule established two levels of prevention program requirements.  Program 3 is essentially the same as OSHA PSM, except that the program also focuses on protecting the public and the environment. Our Program 3 prevention program, which applies to this plant, consists of the following 12 elements:   
 
Employee Participation - We provide for participation by it's employees in all aspects of our process operations. Employees are actively involved in the maintenance of our process safety programs.   
 
Process Safety Information - We maintain a variety of technical documents that are used to help ensure safe operation of our processes.  These documents address:   
1) Physical properties of hazardous substances handled 
2) Operating parameters of the equipment 
3) Design basis and configuration of the equipment   
 
 
Material safety data sheets (MSDSs) document the physical properties of hazardous substances handled, including regulated substances in covered processes.  MSDSs for hazardous substances handled in each process are available in the Plant's MSDS book so that personnel have ready reference to this information. The information available for each hazardous substance typically includes:   
1) Toxicity information and permissible exposure limits 
2) Physical data (e.g., boiling point, melting point, flash point) 
3) Reactivity and corrosivity data 
4) Thermal and chemical stability data 
5) Hazards of mixing substances in the process.   
 
The engineering design documents include the operating parameters and the design basis and configuration of the equipment in each covered process.  The available information includes: 
1) Operating parameters 
2) Simplified process flow diagrams 
3) Maximum intended inventories 
4) Safe upper and lower limits for parameters such as temperature, pressure or flow 
5) Co 
nsequences of deviations from established operating limits 
6) Design basis and configuration of equipment 
7) Piping and instrument diagrams, including materials of construction 
8) Electrical classification 
9) Safety systems 
10) Applicable design codes and standards 
11) Design basis for relief and, if applicable, ventilation systems.   
 
Process Hazard Analysis - This facility has a comprehensive program to help ensure that hazards associated with the covered 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 What-If?/ Checklist analysis technique is the primary tool used 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 measu 
res, 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 company corporate management for resolution.  To help ensure that the process controls and/or process hazards do not eventually deviate significantly from the original design safety features, the plant updates and revalidates the hazard analysis results at least once every 5 years.    
 
Operating Procedures - This facility maintains written operating procedures that address various modes of process operations. These procedures are 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.  These procedures provide guidance on how to respond to upper or lower limit deviations for specific process or equipment parameters.  This information, along with written ope 
rating procedures, is readily available to operators in the process unit and for other personnel to use as necessary to safely perform their job tasks.   
 
Training - To complement the written procedures for process operations, this facility has implemented a comprehensive training program for all employees involved in operating a process.  New employees receive basic training in gas plant operations if they are not already familiar with such operations.  After successfully completing this training, a new operator is paired with a qualified operator to learn process-specific duties and tasks.  All of this training is documented for each operator, including the means used to verify that the operator understood the training.  To ensure training is adequate and serves the safety of employees, operators are consulted with on the type and frequency of their training. 
 
Contractors - This facility uses contractors to supplement its workforce during periods of increased maintenance or constru 
ction 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 
6) inform gas plant personnel of any hazards they find during their work 
 
This is accomplished by providing contractors with a process overview, information about safety and health hazards, emergency response plan requirements, and safe work practices prior to their beginning work. In addition, CIG evaluates contractor safety programs and their past performance before selection of a contractor is made.  Facility personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations. 
 
Pre-startup Safety Reviews (PSSR)  - A PSSR is conducted at this facility for any 
major facility modifications that require 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.     
 
Mechanical Integrity - This facility has well-established practices and procedures to maintain pressure vessels, piping systems, relief and vent systems, controls, pumps and compressors, and emergency shutdown systems and safety systems in a safe operating condition.  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 for pressure vessels).  If a deficiency is identified, employees will correct the deficiency before placing the equipment back into service (if possible), or a managemen 
t of change 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 MI program is quality assurance.  Quality assurance measures are incorporated 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 - This facility has long-standing safe work practices in place to help ensure worker and process safety.  Examples of these include; control of the entry/presence/exit of support personnel, 
a lockout/tagout procedure to ensure isolation of energy sources for equipment undergoing maintenance, 
a procedure for safe removal of hazardous substances before process piping or equipment is opened, 
a permit and procedure to control spark-producing activities (i.e., hot work), and a permit and procedure to ensure that adequate precautions are in pla 
ce before entry into a confined space. 
 
Management of Change - A comprehensive system to manage changes to all covered processes has been developed for this facility. 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.  Affected 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 - Incidents are promptly investigated that result in, or reasonably could have resulted in, a fire/explosion, flammable 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 inc 
ident or a similar incident.  The investigation team documents its findings, develops recommendations to prevent a recurrence, and forwards these results to gas plant management for resolution.  Corrective actions taken in response to the investigation team's findings. 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 five years so that the reports can be reviewed during future PHA revalidations. 
 
Compliance Audits - To help ensure that the accident prevention program is functioning properly, this facility 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 three (3) years.  Both Operations and Corporate staff personnel may participate as audit  
team members.  The audit team develops findings that are forwarded to gas 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 this facility have hazards that must be managed to ensure continued safe operation.     
We have safety features on many units to help; contain/control a release, quickly detect a release, and reduce the consequences of (mitigate) a release. Several safety features are utilized in the covered processes including: 
1) Release detection - Hydrocarbon detectors with alarms, Release containment/control  
2) Process relief valves that discharge to a flare to capture and incinerate episodic releases  
3) Valves to permit isolation of the process (manual or automated)   
4) Automated shutdown systems for specific process parameters ( 
e.g., high pressure and temperature)  5) Release mitigation:  Fire suppression and extinguishing systems. Our employees are trained to fight 
   small fires or initiate an ESD only  
 
 
FIVE YEAR ACCIDENT HISTORY 
This facility has an excellent record of accident prevention over the past five years.  There have been no accidents or incidents in covered process areas in the past five (5) years resulting in offsite effects.   
Our approach is to investigate incidents or events that could have reasonably resulted in an uncontrolled release of hazardous substances, to determine ways to prevent these events from recurring. 
 
 
EMERGENCY RESPONSE PROGRAM 
This facility maintains a written emergency plan, which is in place to protect worker and public safety, as well as the environment.  The Emergency Plan is provided to assist personnel who react to and respond to plant emergencies.  It contains information relating to recognition and reporting of emergencies, minimizing hazards, and actions that m 
ust be taken to protect personnel, property and gas service.  The objective of the Emergency Plan is to assure that personnel who could be involved in an emergency are adequately trained to recognize and deal with emergency situations in an expeditious and safe manner.  
 
Facility personnel are trained to take defensive or incipient firefighting actions. Local fire departments will be responsible for extinguishing fires that have gone beyond the incipient stage. Therefore, this plan is limited to providing guidance for our employees to evacuate the facility and notify the appropriate authorities.    
 
Employees receive training in these procedures as necessary to perform their specific emergency plan duties.  The emergency plan is updated when necessary, based on modifications made to gas plant processes or other facilities.  The emergency plan changes are administered through the Plant Supervisory approval process, which includes informing and/or training affected personnel in the chang 
es.   
 
 
PLANNED CHANGES to IMPROVE SAFETY 
We are committed to operating this facility in a safe manner for workers, the public, and the environment.  Our personnel utilize auditing processes to ensure that this facility complies with safe operations of its processes. Improvements to safety are a continual process at the plant and safety policy and procedure modifications are constantly evolving. Specific changes to control equipment or technology and installation of new mitigation systems are not in progress at this time.
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