Sterling Chemicals Incorporated - Executive Summary

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Sterling Chemicals 
Executive Summary 
Accidental Release Prevention and Emergency Response Policies 
The accidental release prevention and emergency response policies at the Sterling Chemicals Inc. ("Sterling") Texas City, Texas facility ("Texas City Plant") are engrained in the fundamentals of the process safety prevention program.  
In our Texas City Plant, we presently handle chemicals, which are considered hazardous by the Environmental Protection Agency (EPA).  The same properties that make these chemicals valuable as commodities in the production of consumer products also make it necessary to observe specific safety precautions.  These safety precautions are exercised in the handling and production processes to control human and environmental exposure in an effort to reduce the overall threat to our workers as well as the surrounding communities.   
It is Sterling's policy to adhere to all applicable federal, state, and local laws, rules, and regula 
tions.  However, the safe handling of hazardous chemicals is paramount at Sterling and we adhere to standards and recommended practices governing the safe handling of hazardous chemicals to ensure that we have obtained a reasonable level of risk reduction.  Investigation of inherently safer technologies, hazardous chemical inventory reduction and/or elimination studies, and fail safe design applications are a few of the continuous improvements occurring at Sterling.  Safety depends upon our management commitment, the manner in which we handle and process chemicals, the safety devices inherent to our process designs, our operating procedures and philosophies, and the training of our workers. 
We believe that accountability for safety reaches throughout all levels of management at Sterling.  Senior management's commitment and dedication to continued safe operating practices is clearly evident in our organization structure and employee empowerment.  This is no more evident than in our inv 
olvement in the OSHA Voluntary Protection Program ("VPP").  Our participation in VPP is a strong example of management's commitment to the safety of our Texas City Plant.   
We have made extensive improvements to safety and health programs like process safety (prevention) management, emergency preparedness and response, work permitting, and training.  
Additionally, we believe employee involvement is the cornerstone to continued safe operations.  We call it employee ownership and its success is portrayed through our lower injury rates, fewer incidents, and improved operating efficiencies at the Texas City Plant.  Our employees volunteer to participate in a unique program known as 'Sterling Teams to Enhance Plant Safety' (STEPS).  There are currently six active STEPS teams.  They are: a) Employee Health and Wellness, b) Contractor Safety, c) Employee Involvement and Awareness, d) Voluntary Protection Program (VPP), e) Hazard Recognition, and f) Process Safety Management. The teams prese 
nt summary reports of their activities and improvements to senior management each month.   
The Emergency Preparedness and Response Plan outlines procedures for warned and unwarned emergencies that may occur at the plant.  Warned emergencies are usually weather related, such as hurricanes, or freezes.  Unwarned emergencies usually consist of on-site emergencies such as fire, explosion or a chemical release.  Sterling provides the emergency response teams with state-of-the-art equipment and the latest training and procedures.  This ensures prompt mitigation actions during incidents and rapid notification to any surrounding neighborhood that may be inadvertently affected by a plant emergency. 
We maintain policies covering five organizations that make up the overall emergency preparedness and response program for the plant.  These five emergency response organizations include: a) Sterling Fire Brigade, b) Sterling Emergency Medical Technicians, c) Sterling Emergency Wardens, d) Sterling  
Emergency Communications Coordinators, and e) STEPS Emergency Response Improvement Team.  These organizations are capable of responding to onsite and offsite emergencies.  In addition, Sterling is an active member of the Texas City Mutual Aid System. 
Facility Description and Regulated Substances Handled 
Sterling is a wholly owned subsidiary of Sterling Chemicals Holdings, Incorporated.  Sterling is a diversified chemical company.  Its petrochemical business manufactures styrene, acrylonitrile, methanol, acetic acid, plasticizers, sodium cyanide and tertiary butylamine at the Texas City Plant.  Sterling's headquarters are located in Houston, Texas. 
Sterling is a large domestic producer of styrene, the primary end products of which are building products, automotive and boat components, disposable cups and trays, packaging and containers, housewares, tires, audio and video-cassettes, luggage, children's toys, paper coatings, appliance parts and carpet backing.   
Sterling is also a si 
gnificant global producer of acrylonitrile, the primary end products of which are apparel, furnishings, upholstery, household appliances, carpets, and plastics for automotive parts using ABS and SAN polymers.   
In addition, Sterling is a large producer of acetic acid, which is used in many products, including adhesives, cigarette filters and surface coatings.  Other commodity chemicals produced at Sterling include: a) methanol, used as a feedstock for the acetic acid unit.  b) plasticizers, used in the production of insulation, upholstery and plastic molding; and c) tertiary butylamine or TBA, used in the manufacturer of solvents, pharmaceuticals, synthetic rubber and pesticides; sodium cyanide, used in electroplating and precious metals recovery. 
The Texas City Plant covers approximately 290 acres within the Texas City Industrial Complex.   It has marine facilities for receiving sea-going ships and barges, rail facilities for delivery and shipment of chemicals by rail, and a network 
of pipelines supplying needed feedstocks.  It is located at 201 Bay Street South in Texas City, Texas, Galveston County.   
There are 500 Sterling employees at the Texas City Plant, which are represented by eleven union labor organizations.  There may be approximately 900 total workers at the plant at any one time during labor intensive activities such as turnarounds.  
We presently handle both toxic and flammable chemicals, which are considered hazardous by the EPA.  These substances are present in quantities greater than the threshold quantity identified by the RMP regulation and therefore are included in our risk management program.   
Ammonia (anhydrous) - Ammonia is used to produce acrylonitrile. Ammonia is received by refrigerated barge.  It is stored in a refrigerated tank at low pressure.  The storage tank is contained within a concrete bunker to mitigate any failure of the storage tank.  Ammonia is reacted with propylene over a solid-fluidized catalyst at low pressure.  Sterl 
ing has a capacity of approximately 33 metric tons of ammonia. 
Acrylonitrile - The acrylonitrile unit at Sterling has an annual rated production capacity of approximately 740 million pounds.  
Chlorine - Chlorine is used for water treatment at Sterling.  It is received by special equipped truck, designed to transport chlorine one-ton containers.  Approximately 22, one-ton containers may be in use at the Texas City Plant at any one time for the purification of water. 
Hydrogen Chloride (anhydrous) - Hydrogen chloride is received into the plant by tank car (rail service) from Dow Chemical.  These tank cars are temperature controlled and are constantly monitored while inside the plant to ensure that the chemical remains within safe temperatures and pressures.  Each tank car at the Texas City Plant has a capacity of approximately 145,000 pounds.  At any one time, two tank cars may be onsite at the Texas City Plant. 
Hydrocyanic Acid (hydrogen cyanide) - Hydrogen cyanide is a by-product of acr 
ylonitrile manufacturing and is used as a raw material for the production of TBA and sodium cyanide and is also burned as fuel.   
Sulfur Dioxide - Sulfur dioxide one-ton containers are used at the plant.  Sulfur dioxide is used as a polymerization inhibitor for hydrogen cyanide.  It's received by special equipped truck, designed to transport one-ton containers.  At any one time, three one-ton containers of sulfur dioxide may be present onsite at the Texas City Plant. 
Flammable Substances (propane/propylene/natural gas) - Propylene is used to produce acrylonitrile.  It is reacted with ammonia over a solid-fluidized catalyst at low pressure with ammonia to produce acrylonitrile.  Propylene and other flammable materials are supplied to the plant by pipeline. 
Offsite Consequence Analysis (worst-case & alternate-cases) 
The RMP rule requirements for identification and selection of a worst-case hazard scenario are prescriptive and negate most safety systems designed to mitigate an incident 
al release.  Based on EPA defined Offsite Consequence Analysis (OCA) parameters, Sterling has one worst-case hazard scenario for the toxic materials handled onsite and one for the flammables handled.  The worst-case is a scenario resulting from an accidental release that is estimated to create the greatest distance in any direction to an EPA defined concentration (endpoint). 
Sterling's worst-case toxic scenario involves anhydrous hydrogen chloride (HCl).  Hydrogen chloride is received via tank car (rail service) into the plant from Dow Chemical.  These tank cars are insulated. Each car may have a maximum of 145,000 pounds of liquid HCl at any one time. A maximum of two tank cars may be present in the Texas City Plant.  This results in a maximum inventory of 290,000 pounds at any one time.  The worst-case assessment for HCl used the EPA's theoretical assumption that the tank car catastrophically fails and releases its entire contents within 10 minutes.  This scenario completely negates 
any passive mitigation.   
Using the EPA's Offsite Consequence Analysis Guide Document to calculate the greatest downwind distance, it was determined that a hydrogen chloride vapor cloud may extend 16 miles from the plant.  
The worst-case flammable scenario involves the instantaneous failure of a propylene storage vessel and subsequent failure of all active safety systems.  The scenario assumes that the total contents of the propylene storage vessel  (130,100 pounds) detonates and results in a destructive blast wave.  The assessment calculated a blast extending out to 1 psi.  The 1 psi damage plot would extend a maximum distance of 0.43 miles from the propylene storage vessel.   
The EPA rule also prescribes that alternate or more likely accident scenarios involving regulated chemicals are identified.  Each of the regulated chemicals was assessed, using prescriptive EPA scenarios and risk assessment guidelines.  The analysis of the alternate scenarios included mitigation affects from 
both passive and active safety systems.   
The results of the alternate scenario analysis are as follows: 
1. The inadvertent failure of the 6" barge transfer hose during offloading of ammonia into the ammonia storage tank was selected as the alternate case for ammonia.  This failure assumes that the hose suddenly uncouples and releases 12,967 pounds of ammonia.  Evaporation of the liquid ammonia could result in the formation of a vapor cloud extending 0.7 miles from the spill site. 
2. The accidental overfilling of the acrylonitrile storage tank 51T18-1.  Acrylonitrile spills from overflow line into concrete containment area. Typical fill rate for the tank is 1,316 lbs/min and this scenario assumes it takes 10 minutes to detect the spill and mitigate it.  Evaporation of the acrylonitrile in the containment dike could result in the formation of a vapor cloud of acrylonitrile extending 0.53 miles from the spill. 
3. A chlorine leak at a valve connection on a 1.0-inch pipeline that resu 
lts in a complete separation of the pipeline at the valve.  The release is detected and controlled within 15 minutes.  A calculated 1,256 pounds/minute was released during the scenario.  Dispersion of the chlorine gas in the atmosphere could result in a vapor cloud of chlorine extending 0.54 miles from the release point. 
4. A hydrocyanic acid (hydrogen cyanide) leak occurs when a 1/8 inch valve connection shears off of a 3.0 inch pump discharge line.  The release is detected and controlled within 10 minutes.  Approximately 262 pounds/minute was released during the scenario.  Dispersion of the gas in the atmosphere could result in a vapor cloud of hydrogen chloride extending 0.81 miles from the release point. 
5. Hydrogen chloride is released at a 1.0-inch filter drain line.  The release is detected and controlled within 10 minutes.  A calculated 102 pounds/minute was released during the scenario.  Dispersion of the gas in the atmosphere could result in a vapor cloud of hydrogen chlori 
de extending 0.56 miles from the release point. 
6. Sulfur dioxide leak occurs when a 1.0-inch line fails and results in a complete separation from the sulfur dioxide container.  The release is detected and controlled within 10 minutes.  Approximately 1,616 pounds/minute was released during the scenario.  Dispersion of the sulfur dioxide gas in the atmosphere could result in a vapor cloud of sulfur dioxide extending 0.65 miles from the release point. 
7. A motorized construction vehicle inadvertently strikes a 2.0-inch flammable pipeline and completely separates the line.  Plant emergency responders control the flow of flammable gas within 10 minutes.  Inadvertent ignition of the flammable gas cloud results in an overpressure that could extend up to 0.18 miles from the ignition source. 
Accidental Release Program & Chemical-Specific Prevention Steps 
Sterling continues to manage changes to its process chemicals, technology, equipment and procedures for processes covered by OSHA's Proc 
ess Safety Management ("PSM") program.  Sterling's "Management of Change" Safety & Health Procedure (SP-0101) has been a useful tool in helping employees understand how to apply Management of Change ("MOC") to prevent or minimize the potential consequences associated with a catastrophic release of toxic, reactive, flammable, or explosive chemicals at Sterling. 
A core group of Sterling employees serve as Management of Change "Coordinators" for the manufacturing departments and material handling department.  In addition to determining MOC notification needs and authorizing start-ups of facility changes, the MOC Coordinators are responsible for maintaining department MOC logs and records, training employees as needed, and ensuring that necessary changes are made to department procedures and process safety information.  Though not required, many of the MOC Coordinators have also received formal Process Hazard Analysis ("PHA") Facilitator training.  
Depending on the nature of the change,  
Sterling identifies three levels of MOC technical / safety reviews.  Level 1 and 2 MOC reviews require the use of a "Safety/Health/Environmental Checklist" to discuss potential hazards associated with the change and are documented on the MOC Form.  A Level 3 MOC review requires that a PHA be conducted on the change and that a representative from the Safety & Health Department participate.  The facilitator of each PHA must be qualified to do so per Sterling Safety Procedure SP-0131.   
Prior to the startup of a change to a process covered by OSHA 29 CFR 1910.119, a Pre-Startup Safety Review ("PSSR") is held to verify that all appropriate safety information has been updated and that all appropriate reviews are performed and training has been completed. 
Sterling completed 100% of its PHAs by the May 26, 1997 deadline imposed by OSHA.  The 1,345 recommendations generated during these reviews were prioritized using Sterling's Risk Ranking Matrix.  The Manufacturing Team Leaders were respon 
sible for communicating the PHA recommendations to all affected employees, and the Safety & Health Department entered the recommendations into Sterling's PHA Recommendation Tracking database.  Monthly progress reports are continuously sent to management based on updates received from the departments responsible for addressing the recommendations. Of the original recommendations only 288 remain unresolved. 
Sterling began revalidating its PHAs in October 1997 and has completed six revalidations.  Revalidation efforts resulted in the identification of 88 additional recommendations.  The 88 recommendations from these PHAs will also be entered into a tracking database and be the subject of monthly status reports.  
Five year Accident History 
Sterling has a very comprehensive Incident Reporting and Investigation procedural process.  It is defined and explained by SP-0112.  Basically, an incident occurs when a deviation from expected performance has been experienced.  Incidents at Sterling 
are classified into a Class 1, Class 2, or Class 3 incident. 
Class 1 incidents are incidents of a minor nature.  A Preliminary Incident Report ("PIR") is filled out on these incidents and they are investigated and followed-up.  However, a formal investigation is not required for Class 1 incidents.  Class 1 incidents are reviewed at the Plant Manager weekly staff meeting.  Examples of Class 1 incidents are most first aid injuries, equipment trip outs, minor chemical releases not requiring reports to regulatory agencies, etc. 
Class 2 incidents are incidents of a more serious nature.  In addition to the PIR these incidents require a formal investigation.  Examples of Class 2 incidents are recordable injuries, near misses with serious potentials, chemical releases requiring reports to regulatory agencies, etc. 
Class 3 incidents are those that occur in processes covered by the OSHA PSM Standard, which resulted in or could reasonably have resulted in a catastrophic release of highly haza 
rdous chemicals in the workplace.  These incidents require a formal investigation and must also meet requirements over and above those for Class 2 incidents.  RMP offsite incidents and those that could reasonably have resulted in a catastrophic release are also included as Class 3 incidents. 
Formal investigations are conducted by appointed teams.  Root cause and corrective actions are determined and formal reports are written.  Progress regarding corrective action on all investigated incidents is tracked through to completion. 
A number of different systems have been used in the recent past to track recommendations arising from Accident/Incident Investigations.  The system we are presently using consists of maintaining a list of all recommendations that are part of the formal Accident/Incident Investigation Reports that are open.  All of these recommendations and other information relevant to these recommendations have been put into the managed PC computer program. 
The list of recomm 
endations, generated by PC program is distributed to those responsible to make corrections.  Those responsible provide a written response back to the Safety and Health Department regarding the status of the recommendations.  The Safety and Health clerical personnel put this information into the managed PC program and in this way are able to keep track of the recommendation status. 
Sterling has had one accidental release of an EPA regulated chemical within the past five years.  This incident involved sulfur dioxide. 
The incident occurred in 1998 when a vent valve was inadvertently left open and unattended during the transfer of sulfur dioxide.  Approximately 12,227 pounds of sulfur dioxide was released through the top of a 200-foot stack.  Following this incident a substitution of a new catalyst was implemented.  The new catalyst does not require the use of sulfur dioxide.  All of the sulfur dioxide was subsequently removed from the unit to eliminate the potential for other accidental 
Emergency Response Program 
A number of improvements have been made in the emergency response organizations in the last year.  A few of these improvements include the development of the Emergency Procedure Plan ("EPP") and the Fire/Spill Strategic Response Plan, formation of the Emergency Communication Coordinators ("ECC"), and formation of the STEPS Emergency Response Improvement Team. 
In 1995 the Texas City Plant revised its EPP by incorporating it into a graphic format.  The plan is now easier to understand and contains all necessary elements to address each type of emergency.  Also in 1995, a drill was conducted using the EPP to determine the effectiveness of the plan.   
In order to improve emergency response efforts within the plant, Sterling formed the ECC group of volunteers.  The function of this group is to provide: offsite industrial hygiene monitoring during a chemical release incident, perform dispersion modeling in the event of a release, and act as a commun 
ications resource to make notifications and provide pertinent information during an incident. 
The ECC group conducts training on their required duties twice a month.  Training items include the use of industrial hygiene monitoring equipment, radio communication equipment, and the CHARM dispersion modeling system.  The ECC group has made good progress in the last year towards fulfilling their role in the emergency response program at Sterling.  This group plans to continue training on their respective duties in order to improve their response efforts.  Incident command training and further dispersion modeling training is planned for the future. 
The Emergency Response Improvement Team ("ERIT") was formed to coordinate emergency response activities at the plant.  The team looks at each part of emergency response and determines if improvements are needed in areas of training, communications, etc.   
One of the biggest contributions of the ERIT is the coordination of semi-annual emergenc 
y procedure plan drills.  These simulated drills include scenarios of spills or releases that are responded to by emergency response teams.  Every aspect of the drill is critiqued and reviewed to determine improvements that need to be made in each area of emergency response.  All recommendations arising from the critique are tracked until resolved by the ERIT.   
The Sterling Fire Brigade averages between 35 and 40 members and is responsible for handling all fires, spills and rescues within the plant.  The fire brigade is all volunteer and consists of: 
7 One (1) Chief 
7 Four (4) Captains 
7 Four (4) Lieutenants 
7 25 to 30 Fire Fighters 
The fire brigade conducts sessions that consist of classroom and hands-on training bi-monthly on each area of emergency response, including hazardous materials.   Training is conducted by qualified fire brigade officers and documented for each member.  The fire brigade maintains a training curriculum for each level of qualification such as probationary  
firefighter, firefighter, lieutenant, captain, and chief.  The following section contains: 
1.Fire brigade-training curriculums 
2.Officers training spreadsheet 
3.Officers training by individual  
4.Fire brigade training by individual 
5.Training delivered by course since 1/1/94 
The Fire Brigade has acquired several new pieces of fire fighting equipment that will improve the overall emergency response capabilities.  Additionally, the fire brigade has developed a strategic response plan that has preplanning information on each tank and vessel in the plant.  
Planned Improvements to Reduce Risk 
The MOC/PSSR was reviewed and re-written in an effort to make the system more clearly defined and to combine the MOC and PSSR processes.  The result was a more "readable" document with improvements in clearly defined roles and responsibilities.  Additionally, forms and guides were changed to enhance the purposes of the procedure and provide consistency of performance.  Combining the MOC and PSSR p 
rocedures provided for a more natural workflow and improved the emphasis on performance of PSSR's as a result of completing the MOC review. 
The requirements set by the MOC and PSSR components of Sterling's PSM process are rigid and extensive by design in order to provide a good foundation for these two elements.  Improvements in these two areas of PSM will come by achieving closer adherence to the requirements that both components set.  
The employee hazard reporting program is sponsored by the Employee Involvement and Awareness team.  This program consists of various different methods of hazard reporting and safety suggestions for employees. Another employee hazard reporting program is the Safety Awareness Involvement for Employees (SAFE) suggestion program.  This program includes: 
7 Safety suggestion collection points at strategic locations in the plant 
7 A specific mail code for suggestion cards that are mailed 
7 The SAFE hot-line for hazard/suggestion reporting 
A significant imp 
rovement to the hazard reporting program is the development of the SAFE database.  The database allows electronic input of safety suggestions and hazards and a way to track them until resolved.  The database will also provide a means to evaluate trends in employee suggestions and reported hazards in the future.  Further use of this database will enhance the ability of the plant to initiate programs to address the suggestions made or correct the hazards reported. 
Improvement plans for Sterling's accident/incident investigation process include: Sterling is in the process of developing a PSM awareness plan that employees will be trained on annually.  Information on the accident/incident investigation process will be included in the training package.  This will make employees more aware of opportunities for participation, access of investigation reports, etc. 
The method by which recommendations arising from investigations are tracked will be improved.  Plans for improvement focus on impr 
oving our system for tracking recommendations generated by the investigation process and contained in the     formal reports. 
We are currently seeking/evaluating software systems that will allow those who are responsible for corrective actions to input status of the recommendations directly into the computer network system.  This will eliminate mailing out the list of outstanding recommendations, written responses back to Safety and Health, and updating of the list by Safety and Health Department personnel.  This will result in status reports that are more current and closer to complete.
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