Hemlock Semiconductor Corp. - Executive Summary

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Employees of Hemlock Semiconductor operate and maintain all of the processes in a safe and a responsible manner.  Accidental release prevention programs and emergency planning and response programs ensure the safety of our employees and our neighbors, as well as protect the environment.   
This document provides a brief overview of the comprehensive risk management activities that we have designed and implemented, including: 
*  A description of our facility and use of substances regulated by EPA's RMP regulation 
*  A summary of results from our assessment of the potential off site consequences from accidental chemical releases 
*  An overview of our accidental release prevention programs 
*  A summary of the results from the assessment of the potential off site consequences from accidental chemical releases. 
*  An overview of the Accidental Release Prevention Programs. 
*  An overview of planned improvements at th 
e facility to help prevent accidental chemical releases from occurring and adversely affecting our employees, the public, and the environment 
*  A five year accident history for accidental release of chemicals regulated by the EPA's RMP rule.  
*  An overview of the Emergency Planning and Response Programs.  
*  The detailed information (called data elements) about our risk management program 
Our facility produces semiconductor grade silicon for computer chip manufacturers like Intel, Motorola, and Texas Instrument. The silicon is made by reacting hydrogen and trichlorosilane. Chemicals not used in  the reaction are recovered and re-used on site or sold to makers of fiber optic cables for telephone and computer communications. Besides manufacturing, our facility houses the following non-manufacturing teams:  research and development, financial, sales, senior management, power house and utilities, waste treatment, materials movement, safety and loss prevention, e 
rgonomics, industrial hygiene, and environmental services.   
We are a member of the Chemical Manufacturers Association and subscribe to the Responsible Care Codes of Management Practices.  Our core values are: 
Employees - Our employees are the source from which our ideas, actions, and performance flow. The full potential of our people is best realized in an environment that breeds fairness, self-fulfillment, teamwork, and dedication to excellence.  
Integrity - Our integrity is demostrated in our ethical conduct and in our respect for the values cherished by the society of which we are a part.  
Environment - Our commitment to the safekeeping of the physical environment is founded on our appreciation of it as the basis for the existence of life. 
Safety - Our attention to safety is based on our full-time commitment to injury-free work, individual self-worth and a consideration for the well-being of others. 
The facility is ISO 9002 certified and operates under all applicable environm 
ental permits. 
In our processes, we use the following chemicals that EPA has identified as having the potential to cause significant off site consequences in the event of a substantial accidental release: 
RMP Toxic Chemicals 
Hydrogen Chloride (Anhydrous) 
Anhydrous hydrogen chloride is a byproduct of the reaction that makes semiconductor grade silicon.  It is recovered and stored in  two storage tanks.  From there it is shipped over the road in a tank truck several times a day.  
RMP Flammable Chemicals 
Trichlorosilane is one the major reactants in making semiconductor grade silicon.  It is a major feed to all of our reactors.  This substance exists in pure form and mixtures in many areas of the plant including storage tanks, process vessels, and piping.  The largest storage of trichlorosilane is in mixture form.  
Hydrogen is the other major component in making the hyper-pure silicon.  It is stored in liquefied form in two storage tan 
ks.  When it is transferred to the reactors it is vaporized.  Hydrogen exists in process vessels, piping, and the storage tanks noted above.  It is also recovered for reuse in the facility. 
Dichlorosilane is a minor byproduct of our silicon producing reactors.  It is separated from other chlorosilanes and sold  as pure in small quantity cylinders.  Large quantities of dichlorosilane exist in mixtures only.    
Other Chemicals Manufactured or Used at the Facility 
Other major chemicals used at this facility are silicon tetrachloride, nitric acid, and hydrofluoric acid. Although these chemicals are not specifically covered by the RMP rule, all processes that contain these chemicals are included in the facility's Process Safety Management Program.   
Our accidental release prevention programs and our emergency planning and response program help us effectively manage the hazards that are posed to our employees, the public, and the environment by our use of these chemicals. 
EPA's RMP rule requires that we provide information about the worst-case release scenario(s) and alternative release scenario(s) for our facility.  The following are brief summaries of these scenarios, including information about the key administrative controls and mitigation measures to limit the exposure distances for each scenario: 
Worst-case Toxic Release Scenario - Hydrogen Chloride (Anhydrous) 
Our worst case scenario is the sudden release of the maximum volume that could ever be present in one of our HCl tanks. Consequences of such a release could spread  beyond our plant boundaries. In an effort to reduce this risk, we have written operating procedures that  limit the inventory to one third of the tank capacity. Nonetheless, the worst case scenario provides an opportunity for more community  dialogue on prevention and emergency response.  
Alternative Toxic Release Scenario - Hydrogen Chloride (Anhydrous) 
Our alternative scenario was  
selected in accordance with our emergency planning goal which is to ensure that our emergency response plan and the community emergency response plan address all reasonable contingency cases.  Since we have never had a major accidental release, we selected our alternative scenario from a list of serous incidents that have occurred at other companies throughout the U.S.. Our alternative scenario is: 
7 6000 gallons of HCl leaking through a hole in a pipe over a 90 minute period. 
7 Upon exiting the hole the hydrogen chloride liquid  would  vaporize and mix with air creating a vapor cloud. The cloud would be concentrated nearest the plant, and gradually dilute as wind pushes it away from the plant. 
7 Within two miles of the release point, concentrations would be moderate to high, and if people immediately followed shelter-in-place procedures, serious and irreversible health effects would be minimized. 
7 Beyond two miles, the release may be noticeable, but serious health effects would be un 
Should a major release occur, all HSC production employees are trained to respond as an organized team to minimize the effects on neighbors in the following four ways: 
- Activate the community warning siren and telephone dialing system 
- Nearest to the release point, employees with special protective suits would enter the vapor cloud to shut isolation valves 
- Around the perimeter, other employees would activate water sprays to dilute the vapor cloud 
- Downwind, employees would measure concentrations to help emergency responders take appropriate protective measures. 
In addition, Thomas and Richland Township fire and police departments would follow a plan prepared by the Saginaw County Local Emergency Planning Committee (LEPC) designed to protect neighbors. 
There is one day care facility within the two mile radius. No schools, homes for the elderly, or hospitals are located within the two mile radius. However, there are residential areas within the two mile radius. Though chan 
ces of a catastrophic release are remote, we have installed a community warning system consisting of special sirens to alert residents within one mile of the plant, and an automated telephone dialing system that can reach to 3 miles. Each year, residents within three miles  are mailed information on the warning systems and sheltering procedures as well as invited to an open house where there are opportunities to dialogue with plant personnel. 
Worst-case Flammable Release Scenario - Trichlorosilane/Dichlorosilane Mixture 
The  RMP rule requires that we assume a major spill of our flammable chemicals would quickly vaporize and explode. Assuming that our largest tank of flammable spills its entire contents of a mixture of trichlorosilane, dichlorosilane, and silicon tetrachloride, and an explosion occurs, the  concussion (1 psi) could be large enough to break windows at residences within a half mile of our facility. Because the mixture does not easily vaporize when spilled, we think it is 
impossible to get a large enough vapor accumulation to explode and affect our neighbors. Instead, upon exiting the tank, the liquid mixture would drain into a nearby sump designed large enough to contain the entire tank contents. We would then spread foam on it to prevent vaporization and mixing with air.  
Alternative Flammable Release Scenario- Trichlorosilane/Dichlorosilane Mixture 
The largest leak we think possible is a =" pipe leak that could occur for about 20 minutes designed large enough to capture the entire tank contents. About 2000 gallons would drain into a nearby sump. Emergency crews would spread foam on top of the pool to prevent it from vaporizing and mixing with air.  
We take a systematic, proactive approach to preventing accidental releases of hazardous chemicals.  Our management systems address each of the key features of successful prevention programs including: 
*  Process saf 
ety information 
*  Process hazard analysis 
*  Standard operating procedures 
*  Standard maintenance procedures 
*  Training 
*  Mechanical integrity 
*  Management of change 
*  Pre-startup review 
*  Compliance audits 
*  Incident investigation 
*  Employee participation 
*  Hot work permit 
*  Safe work permit 
*  Contractors 
*  Trade Secrets 
*  Emergency planning and response 
At HSC we take safety very seriously. Industry standards are used for design and construction. Our operating  and maintenance personnel are trained, tested, and certified. Operators inspect their area for small leaks daily. Technicians routinely measure the wall thickness of tanks and pipes. Employees regularly review processes and process changes for potential hazards by asking "what if" questions.  They also participate in a complete hazards analysis review of each  process every 5 years.  Recommendations for additional safeguards identified from these reviews are tracked to completion through the site  
Recommendation Management System.   
These individual elements of our prevention program work together to prevent accidental chemical releases.  Hemlock Semiconductor is committed to the standard that these management systems set for the way we do business, and we have specific accountabilities and controls to ensure that we are meeting our own high standards for accident prevention.   
Hemlock Semiconductor keeps records for all significant accidental chemical releases that occur at our facility.  Especially those releases that injure people on our site or affect our neighbors.  The following is a brief summary of accidental chemical releases involving materials covered under EPA's RMP rule during the past five years: 
           1994    1995    1996    1997    1998 
Hydrogen Chloride        0    0    1    0    0 
Trichlorosilane        0    0    0    0    0 
Dichlorosilane        0    0    0    0    0 
Hydrogen          0    0    0    0    0 
For each of these incidents, we have conducted formal incident investigations to identify and correct th 
e root causes of the events. To prevent the 1996 release from re-occurring, we increased the pressure rating of our tanks so they can withstand pressure excursions caused by plant electrical upsets without venting. 
We maintain an integrated contingency plan, which consolidates all of the various federal, state, and local regulatory requirements for emergency response planning.  Our program provides the essential planning and training for effectively protecting workers, the public, and the environment during emergency situations.  Furthermore, HSC has coordinated its plan with the Saginaw County Local Emergency Planning Committee.   
The HSC site Emergency Planning and Response plan is documented in the site emergency manual.  It is outlined as follows: 
- General information 
- Emergency System/Notification 
- Incident Command System 
- Hazardous Material Response 
- Fire Brigade (incipient) 
- Emergency Medical Service 
- Waste Management 
- Security  
- Natural D 
- Communications 
- Evacuation - Head count 
- Public Relations 
- Unit Plans 
- Waste Management Contingency Plan 
- Post Incident Follow-up 
- Special Response Plans 
- Emergency Response Drill Standard 
The following is a list of improvements that we are planning to implement at the facility to help prevent and/or better respond to accidental chemical releases: 
- Additional video cameras with sitewide views. 
- Additional automatic shutoff valves. 
- Expansion of emergency telephone dialing systems (add 16 more lines)
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