Equistar Chocolate Bayou Chemical Complex - Executive Summary

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Risk Management Plan Executive Summary 
Equistar Chemicals, LP 
Chocolate Bayou Chemical Complex 
 
1. Purpose 
 
This document describes the Equistar Chemicals Chocolate Bayou Chemical Complex's philosophy and procedures for managing risk to employee health, public safety and to the environment.  It is intended to be just a summary of the many policies, procedures and actions that are taken to prevent or mitigate the potential release of chemicals listed under EPA 40 CFR 68 Accidental Release Prevention Requirements: Risk Management Programs (RMP) Under the Clean Air Act, Section 112(r)(7). 
 
2. Plant Overview 
 
The Equistar Chocolate Bayou Chemical Complex is an Olefins and Aromatics production facility.  It manufactures a variety of petrochemical products, which are used by others to manufacture a wide range of products from plastics to gasoline additives.  The complex consists of two production units, the Olefins Unit and the Hydrocarbons Unit and a Distribution Tank Farm Area.  The two un 
its and the tank farm are fully integrated and interconnected in the production of Olefins and Aromatics and are treated, for the purposes of RMP, as a single process.  The process all starts in what is called the Olefins Unit, where plant feedstock is "cracked" in a furnace.  The feedstock is a mixture of naturally occurring hydrocarbons that range from natural gasoline, through gas well condensates, to heavy diesels.    In "cracking", the hydrocarbon chains are broken into shorter chains and in some cases recombined into even longer chains of hydrocarbons.  The result is a mixture of many hydrocarbons, which must be separated (and in some cases reacted with hydrogen) in order to become usable products.  The Equistar Chocolate Bayou Chemical Complex manufactures the following products; Ethylene, Propylene, Ethane, Pyrolysis Gasoline, Heavy Aromatic Oil (HAO), Light Pyrolysis Oil, Pyrolysis Tar, Dicyclopentadiene (DCPD), Raffinate I, Raffinate II, Resin Oil, Benzene, Butadiene, Mixed C 
4 Hydrocarbons, Toluene, and UDEX Raffinate, Methyl-Tert-Butyl-Ether (MTBE), and Isoprene.  In addition to these products, the following are used as feedstocks to the plant in making the products; Olefins Unit Feedstock as described above, Ethane, Butane, Drip Oils and Methanol.  The feedstocks are all transported to the facility by pipeline or barge and the products are transported from the facility by barge, pipeline or tank truck. 
 
3. Accidental Release Prevention and Emergency Response Policies 
 
Equistar is committed to employee, public and environmental safety.  This commitment is inherent to a comprehensive accidental release prevention program that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at Equistar.  It is our policy to implement appropriate controls to prevent and mitigate possible releases of regulated substances.  Unforeseeably, if such a release does occur, our trained emergency respon 
se personnel are on hand to control and mitigate the effects of the release.  We also coordinate with the Chocolate Bayou Mutual Aid Group which provides additional emergency response resources. 
 
4. The Stationary Source and the Regulated Substances Handled 
 
The Equistar Chocolate Bayou Chemical Complex encompasses Olefins and Aromatics manufacturing.  In the process of manufacturing these chemicals, some of which are regulated substances, we handle several flammable mixtures, comprising of eighteen (18) regulated flammable substances, and we utilize one (1) toxic regulated substance.  The eighteen (18) regulated flammable substances are: 1-3 Butadiene, Butane, Butene, Ethane, Ethylene, Hydrogen, Isobutane, Isopentane, Isoprene, Methane, Methyl Butene, 1-3 Pentadiene, Pentane, Pentene, Propadiene, Propane, Propylene, and Vinyl Acetylene.  The one (1) toxic regulated substance is Chlorine used as a cooling water treatment chemical. 
 
5. The Worse-Case Release Scenarios and the Alternativ 
e Release Scenarios, including administrative controls and mitigation measures to limit the distances for each scenario 
 
Methodology given in the RMP Offsite Consequence Analysis Guidance by the EPA and the EPA RMP*Comp computer software were employed by Equistar to perform worst and alternative case release scenarios.  The following paragraphs provide details of the chosen scenarios. 
 
A.  Toxic Worse Case Release Scenario 
 
The worse-case release scenario submitted for Program 3 toxic substances involves a catastrophic release of chlorine from a single one ton (2000 lb.) cylinder.  Chlorine is used as a cooling water treatment chemical in the two cooling towers in the Olefins and Aromatics manufacturing process.  The scenario assumes the complete loss of containment of a single storage cylinder of 2,000 pounds of chlorine as a liquid under pressure.  Under worse-case weather conditions, the maximum distance exceeds the plant fence line with an endpoint of 0.0087 mg/L.  No administrativ 
e controls or passive mitigation measures were taken into account when estimating the maximum distance to the toxic end point. 
 
B.  Toxic Alternative Case Release Scenario 
 
The alternative case release scenario submitted for Program 3 toxic substances involves a release of chlorine from a <" diameter hole in the liquid portion of the storage cylinder.  The release results in an estimated release rate of 160 lb./min. for 10 minutes. Under neutral weather conditions for this alternative release scenario, the maximum distance exceeds the plant fence line with an endpoint of 0.0087 mg/L.  No administrative controls or passive mitigation measures were taken into account when estimating the maximum distance to the toxic end point.  
 
For both toxic release scenarios, no credit was taken for active mitigation and emergency response actions that would normally occur to prevent or reduce the possible releases.  Such active mitigation measures that are in-place are: Chlorine detection system to a 
lert operating personnel of a chlorine release, visual inspection of Chlorine cylinders upon receipt by operations personnel, emergency response personnel being fully trained in the application of a Chlorine cylinder leak repair kit which is kept on site for use in case of just such a scenario, emergency response personnel have full personnel protective equipment (PPE) available to allow them access to the cylinder even during a release, and fire water monitors available to spray down the leak area.  Chlorine is highly soluble in water so that a water spray can greatly limit the size of the toxic release. 
 
C.  Flammable Worse-Case Release Scenarios 
 
The first worse-case release scenario submitted for Program 3 flammable substances involves a catastrophic release of a Olefins Unit feedstock storage tank in the Olefins and Aromatics manufacturing process.  The scenario assumes the complete loss of containment of 68,000,000 lb. of feedstock as a flammable mixture of hydrocarbons which vap 
orizes, finds an ignition source, with 10 percent of the released quantity participating in a vapor cloud explosion.  Under worse-case weather conditions, the maximum distance exceeds the plant fence line with an endpoint of 1 psi overpressure.  This scenario assumes that the standard administrative control of limiting the tank level to a maximum of 89% of the shell volume is in effect. 
 
This first flammable worse-case scenario makes use of several assumptions that are required by the RMP rule for flammable mixtures.  It is assumed that the tank is filled entirely of the most flammable feedstock used.  This is a highly conservative assumption since such volatile feedstocks are normally blended with less volatile feedstocks to reduce the vapor pressure of the mixture to allow storage in an atmospheric tank.  Additionally, feedstock market supply conditions limit the availability of such volatile feedstocks, severely reducing the maximum amount of any volatile feedstock that could be pla 
ced in a given tank.  These same volatile Olefins Unit feedstocks are a NFPA rated 4 flammable liquid, due to the rather high content of what are called "light" hydrocarbons.  These "light" hydrocarbons are the components of the mixture that are regulated flammable substances under the RMP rule.  Even though the "light" components of the mixture account for less than 32% of the mixture, for the purposes of consequence analysis, the entire mass of the mixture is treated as if it were a flammable regulated substance.  This RMP required treatment, of this particular flammable mixture, is thought to be very conservative.  Since all of the various Olefins Unit feedstocks are blended together with the specific intent to control the volatility of the mixture, it is highly improbable that the lightest feedstock would be allowed to fill an entire tank.  In the event of a catastrophic failure of an Olefins Unit feedstock tank, it is highly unlikely that sufficient heat and mass transfer could oc 
cur for the mixture to sufficiently vaporize the regulated flammable substances in a sufficient quantity to create a flammable vapor cloud explosion.  Due to the above RMP rule required assumptions and the very large size of the Olefins Unit feedstock storage tank, this worse-case scenario is several times larger than the next possible worse-case scenario.  From a physical chemistry perspective, the above worse-case scenario is not possible.  With the goal of presenting what is thought to be more technically accurate worse-case scenario, a second flammable worse-case scenario is also presented. 
 
The second worse-case release scenario submitted for Program 3 flammable substances involves a catastrophic release of Mixed C4's Hydrocarbon product from a storage sphere in the Olefins and Aromatics manufacturing process.  The scenario assumes the complete loss of containment of 7,800,000 lb. of Mixed C4's as a flammable mixture of pressurized liquid hydrocarbons which vaporizes, finds an ign 
ition source, with 10 percent of the released quantity participating in a vapor cloud explosion.  Under worse-case weather conditions, the maximum distance exceeds the plant fence line with an endpoint of 1 psi overpressure.  This scenario assumes that the standard administrative control of limiting the tank level to a maximum of 89% of the shell volume is in effect.  Since the entire product is a mixture of RMP regulated flammable substances, the potential to vaporize the material into a vapor cloud upon release is possible. 
 
 
D.  Flammable Alternative Case Release Scenario 
 
The alternative release scenario submitted for Program 3 flammable substances involves the shaft seal failure of a barge loading pump for Butadiene product in the Olefins and Aromatics manufacturing process.  The scenario assumes the release of 320,000 lb. of Butadiene product as a flammable mixture of hydrocarbons which vaporizes, finds an ignition source, with 10 percent of the released quantity participating in 
a vapor cloud explosion.  Under worse-case weather conditions, the maximum distance exceeds the plant fence line with an endpoint of 1 psi overpressure.   
 
For the two worse-case flammable release scenarios and for the one alternative flammable release scenario, no credit was taken for active mitigation and emergency response actions that would normally occur to prevent or reduce the possible releases.  Such active mitigation measures that are in-place are: Vapor detection systems to alert operating personnel of a hydrocarbon release, process controls and interlocks which allow transfer of material from a leak/spill to other tanks, dikes which contain the spill and limit the area to which it can spread, fire water monitors and deluge systems, and a fully trained emergency response fire brigade. 
6. The General Accidental Release Prevention Program and the Chemical Specific Prevention Steps 
 
Equistar has taken the necessary steps to comply with the accidental release prevention require 
ments set out under 40 CFR Part 68.  This facility was designed, constructed, and is maintained in accordance with many national Codes and Standards too numerous to mention in this short summary.  Codes or Standards from the following major organizations are used: ASME, ANSI, API, IEEE, NFPA, ASTM and ISA.  All of the processes at the Equistar Chocolate Bayou Chemical Complex are subject to the OSHA PSM standard under 29 CFR 1910.119. 
 
Also, Equistar at the Chocolate Bayou Chemical Complex has taken the additional leadership step of becoming a member of the OSHA Voluntary Protection Program (VPP).  As a VPP Star Work Site, this facility has gone above and beyond the normal industry safety requirements by committing to the philosophy of continuous improvement in safety performance.  This dedication on the part of the management and the employees of the site, ensures that we will continue to push for reductions in incidents and improvements in reducing the potential hazards associated wi 
th our processes. 
 
The following sections briefly describe the elements of the release prevention program in place at Equistar. 
 
Process Safety Information 
Equistar maintains a record of written safety information that describes the chemical hazards, operating parameters and equipment designs associated with all processes. 
 
Process Hazards Analysis 
Equistar conducts studies to ensure that hazards associated with our processes are identified and controlled efficiently.  The methodology used to carry out the analysis is referred to as a Unit Process Hazards Review (PHR).  A team of qualified personnel with expertise and knowledge of the process technology and plant operations undertake the studies.  A person knowledgeable of the PHR process being used leads the team.  Any findings related to the PHR are addressed in a timely manner. 
 
Operations Procedures 
For the purposes of operating our facilities safely, Equistar maintains written operating procedures.  These procedures address variou 
s modes of operation such as initial startup, normal operations, temporary operations, emergency operations, emergency shutdown, normal shutdown and startup after a turnaround.  The information is regularly reviewed and is readily accessible to operating technicians involved with the process. 
 
Training 
Equistar has a training program in place to ensure that employees that are operating processes are competent in the operating procedures associated with these processes.  New employees receive basic training in process operations followed by on-the-job supervision along with additional training until they are qualified to work independently.  Refresher training is provided at least every three years and more frequently as needed. 
 
Mechanical Integrity 
Equistar carries out documented maintenance inspections and testing of process equipment and controls to ensure proper functions.  Process equipment examined by these inspections and checks includes among others; pressure vessels, storage t 
anks, piping systems, relief valves and flare systems, pumps, compressors and fire water deluge/monitor systems.  Some instruments that are inspected and checked include; emergency shutdown systems, interlocks and alarms, process controls, and vapor detection systems.  Only qualified maintenance personnel who have received previous training in maintenance practices are allowed to carry out maintenance.  Furthermore, these personnel are offered specialized training as needed.  Equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner. 
 
Management of Change 
Written procedures are in place at Equistar to manage changes to the process chemicals, technology, equipment and procedures.  Process operating technicians, maintenance personnel or any other employee whose task are affected by a modification in process conditions are promptly made aware, and trained as needed, of the change. 
 
Pre-Startup Safety Review 
Pre-Startup Safety Reviews related to 
new processes and to modifications to existing processes are conducted as a regular practice at Equistar.  These reviews are conducted to confirm that the facility's construction, equipment, and the operating/maintenance procedures are suitable for safe startup prior to placing the equipment into service/operation. 
 
Compliance Audits 
Equistar conducts audits on a regular basis to determine whether the provisions set out under the RMP rule are being implemented.  These audits are carried out annually and corrective actions required as a result of the audits are undertaken in a safe and prompt manner. 
 
Incident Investigations 
Equistar investigates any incident that has resulted in, or could reasonably have resulted in, an employee injury or a catastrophic release of a hazardous material.  These investigations are undertaken to identify the root cause leading to the incident as well as identify any corrective actions needed to prevent reoccurrence. 
 
Employee Participation 
Equistar believ 
es that process safety management and accident prevention is a team effort.  All company employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements.  In addition, many of the various elements of the release prevention program require employee participation as the normal procedure for implementation of that element.  All employees have access to all information created as a part of the facilities implementation to the RMP rule, particularly information resulting from the process hazards analysis. 
 
Hot Work Permits 
At Equistar all hot work on covered processes requires an approved Hot Work Permit.  Employees and contractors are trained to recognize when a Hot Work Permit is required and in how to initiate obtaining such a permit.  Operations technicians ensure that the required Hot Work Permit safety precautions are fully implemented prior to signing the permit and allowing work to begin.  Personnel affected by the Hot Wor 
k Permit Procedure receive specific procedural training on an annual basis. 
 
Contractors 
When selecting a contractor, a thorough evaluation of the safety performance of the contractor is carried out to determine if the contractor should even be allowed to submit a proposal.  Additionally, Equistar routinely monitors the safety performance of all our contractors to ensure adequate performance.  Equistar has a strict policy of informing the contractors of known potential hazards related to the contractors work and to the potential process hazards of the area the contractor will be working in.  Contractors are also informed of the procedural actions that they are to take during an emergency response situation. 
 
7. Five Year Accident History 
 
Equistar Chocolate Bayou Chemical Complex has an excellent record of preventing accidental releases over the last 5 years.  Due to our release prevention policies, there has been no accidental release of substances regulated by the RMP rule, in the la 
st 5 years, that had an onsite or offsite impact as described under EPA 40 CFR Part 68.42(a).  As a matter of course, Equistar reports and investigates all incidents.  The number and severity of incidents has been declining for the last three years.  This decrease in number can be seen in the incidents that resulted in an OSHA recordable injury as listed below: 
 
Year  Number of Incidents  Recordable Injuries 
1994               5                                 5 
1995               6                                 6 
1996               0                                 0 
1997               0                                 0 
1998               1                                 1 
 
The emphasis that all incidents are to be reported and investigated assists in improving all safety performance including accidental releases of regulated RMP substances. 
 
8. Emergency Response Plan 
 
Equistar has in place a written Emergency Response Plan to deal with accidental releases of hazardous materials. 
 The plan includes many aspects of emergency response including; fire fighting, adequate first aid and medical treatment, shelter in place, evacuations, notification of Brazoria County Local Emergency Planning Committee (LEPC) with which our emergency plan has been coordinated and verified, and notification of the public through our Community Alert Network (CAN) system.  Our CAN system is an automatic phone system that calls all neighbor phones with a recorded message that provides key actions to be taken in the event of an emergency.  The plant also has an online computer release modeling system called "Safer" which uses current meteorological data and chemical release information to predict the direction, distance and concentration of the release plume.  Additionally, the Equistar Chocolate Bayou Chemical Complex has a program call Special Situations Plan (SSP) which is an emergency assistance program of plant personnel to the surrounding community.  The SSP is activated anytime an  
emergency could possibly have effects off the plant site. 
 
To ensure proper functioning, our emergency response plans are periodically drilled and practiced.  Our emergency response equipment is regularly inspected and serviced.  And of course, the plan is reviewed and updated as needed to reflect any pertinent changes taking place within our processes that would require a modified emergency response. 
 
9. Planned Changes to Improve Safety 
 
Several developments and findings have resulted from the implementation of various elements of our accidental release prevention program.   The following are just some of the items that were identified during unit PHAs and are being planned for installation. 
7 Additional vapor detection points in the Olefins Unit 
7 Revisions to operating procedures to help alert operating personnel to help prevent a potential auto-refrigeration  excursion 
7 Additional relief protection 
7 Revisions to the emergency operating procedures to allow a more rapid response i 
n the event of a major release 
Completion of these action items should reduce the probability of, the potential for and/or the  consequence of, a release of RMP regulated chemicals.
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