Foamex Morristown Plant #1 - Executive Summary

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EXECUTIVE SUMMARY 
 
Accidental release prevention and emergency response policies 
 
At the Foamex LP Plant in Morristown, TN, we handle toluene diisocyanate (TDI), which is considered hazardous and regulated by the EPA.  The same properties that make TDI valuable for use at our facility also make it necessary to observe certain safety precautions in the handling of the substance.  Safety precautions have been implemented to prevent unnecessary human exposure, to reduce the threat to our own personal health as well as our co-workers, and to reduce the threat to nearby members of our community.  It is our policy to adhere to all applicable federal and state rules and regulations. 
 
We are committed to the safety of our employees and the public, and to the preservation of the environment, through the prevention of accidental releases of hazardous substances.  Successful implementation of our accidental release prevention program will help ensure that emergencies are unlikely and reduce the l 
ikelihood that emergency response procedures will be needed.  Nevertheless, an emergency such as a release of TDI is possible.  We have emergency response procedures to help ensure that accidents will be mitigated properly without undue risk to the public, environment, employees, contractors, or other personnel within the plant. 
 
Description of the facility and the regulated substances handled 
 
The primary purpose of this facility is to produce flexible polyurethane foam, which is sold to other facilities and used to produce bedding, furniture, and a number of other products.  TDI is one of the reactants required to produce polyurethane foam.  TDI is received by rail car and by tank truck, and is stored in indoor storage tanks.  The maximum quantity of TDI stored in rail cars and in storage tanks at our plant is about 900,000 pounds.  The TDI is piped to a mix head where it is mixed with other reactants to produce a slab of polyurethane foam.  The foam is conveyed to cutting stations w 
here it is cut to the size and shape specified by our customers. 
 
 
TDI is the only substance handled at our plant that is regulated by EPA's risk management program (RMP) rule.  TDI is covered because the maximum quantity stored onsite exceed EPA's threshold quantity (TQ) of 10,000 pounds. 
 
Offsite consequence analysis of release scenarios 
 
An offsite consequence analysis (OCA) was performed to estimate the potential for an accidental release to affect the public or the environment.  The OCA consists of evaluating worst case release scenarios (WRSs) and alternative release scenarios (ARSs).  We do not expect a worst case release scenario to ever occur.  An ARS represents a release that might occur during the lifetime of a facility like ours.  ARSs help us to work with the local emergency planning committee (LEPC) to improve the community emergency response plan. 
 
The main objective of performing the OCA is to determine the distance at which certain effects might occur to the public bec 
ause of an accidental release (called the endpoint distance).  The following effects could occur at the endpoint distance: 
 
* Most people at the endpoint distance of a TDI release would be able to walk away from the exposure without any long-term health consequences, although some short-term consequences (e.g., strong eye or throat irritation) are likely.  Some people who are particularly susceptible to the released substance could be incapacitated. 
 
Worst case release scenarios.  Catastrophic failure of a TDI rail car, having a capacity of 200,000 lbs. TDI, would be a worst case release for a toxic substance because a TDI rail car is the largest outdoor TDI container at the plant.  The TDI vendors limit the quantity of TDI loaded into a railcar to 192,000 lbs. maximum to allow space for thermal expansion during possible heating of the TDI.  During cold weather, we pre-heat the TDI to a maximum temperature of 95xF to facilitate unloading and prevent TDI solidification.  During hot weat 
her, the TDI temperature could reach the maximum ambient temperature of 100xF.  Because a release at a higher temperature will result in the greatest endpoint distance, we assumed the release would occur at 100xF.  We also assumed that the entire contents of the railcar would be released as a liquid, form a pool that would spread to cover an area of approximately 76,800 ft2 with a depth of about 0.4 inches (1 cm), and evaporate to form a cloud that would disperse downwind.  Refined dispersion modeling predicts a distance of 477ft. from the rail car to the TDI toxic endpoint concentration of 0.98 ppm (0.007 mg/L). 
 
Alternate Release Scenarios.  Rupture of the transfer line from the railcar-unloading pump to the TDI storage tank would release TDI to the ground at the standard pump rate of  530 LB/min.  We assumed that the release would continue for the 10 minutes required for an employee to stop the pump using remote emergency shutdown controls.  The resulting pool would spread to cover  
an area of approximately 2,120 ft2 with a depth of 0.4 inches and evaporate to form a cloud that would disperse downwind.  Refined dispersion modeling predicts a distance of less than 33 ft. from the pool to the TDI toxic endpoint concentration of 0.98 ppm. 
 
 
The general accidental release prevention program and specific prevention steps 
 
The plant has implemented programs and procedures that comply with EPA's Level 2 Accidental Release Prevention Program Rule.  Our facility qualifies for Level 2 coverage because (1) our worst case release scenarios for TDI can impact persons across the property boundary of the nearest public receptor, and (2) TDI is not a substance covered by OSHA's process safety management standard (PSM).  Our accidental release program is designed to systematically accomplish the following functions: 
 
- Control the creation and retention of safety information regarding the regulated substances, processes and equipment 
- Conduct hazard reviews to identify, evaluate, 
and control process hazards associated with the regulated substances, processes, and procedures 
- Create, maintain, and evaluate operating procedures for activities within or near processes that use regulated substances 
 
The general accidental release prevention program and specific prevention steps (continued) 
 
- Provide training for personnel who operate covered processes so that they safely perform their jobs 
- Monitor and control maintenance activities that can affect the mechanical integrity of equipment used in covered processes 
- Confirm through compliance audits that RMP practices at the plant are consistent with our written programs and that the programs are adequate to address all of the requirements of the RMP rule 
- Ensure that process incidents, particularly those of catastrophic magnitude or potential, are thoroughly investigated using our incident investigation procedures and that relevant findings are communicated throughout the company to help prevent recurrence 
 
 
The 
TDI process at our plant has hazards that are carefully managed to ensure continued safe operation.  The prevention program outlined above is applied to the TDI process.  Collectively, these prevention program activities help prevent potential accidental releases that could be caused by equipment failures, human errors, and by management system failures. 
 
In addition to the accidental release prevention program, our plant has safety features on many units to help (1) contain or control a release, (2) quickly detect a release, and (3) reduce the consequences of or mitigate a release.  The following types of safety features are used in various units of the TDI process: 
 
Release detection  
 
- Process Alarms 
- Video Monitors     
- Operator Surveillance Activities 
 
Release Containment/Control 
 
- TDI storage tanks are piped to overflow into other vessels 
- Curbing or dikes to contain TDI liquid releases 
- TDI storage tanks located inside an enclosed building 
- Automated shutdown systems for cr 
itical process parameters (e.g. high level, high pressure) 
- Pressure/vacuum relief devices on vessels to prevent rupture or collapse 
- Remote shutdown of unloading and transfer pumps 
- Magnetic drive TDI centrifugal pumps without seals 
- Valves to permit isolation of the process 
- TDI railcar inner tank is surrounded by an outer shell filled with insulation 
- TDI railcars are top unloaded through a nozzle in the top of the tank 
- Vapor from storage tank is piped or hosed to the unloading vessel 
 
The general accidental release prevention program and specific prevention steps (continued) 
 
Release Mitigation 
 
- Fire suppression and extinguishing systems 
- Trained emergency response personnel 
- Personal protective equipment (e.g., protective clothing, self-contained breathing apparatus, breathing air stations) 
 
Five-year accident history 
 
We have had no releases of TDI in the last 5 years that resulted in deaths, injuries, or significant property damage on site, or known deaths, injuries, 
evacuations, sheltering-in-place, property damage, or environmental damage off site.  We have had 1 small release of TDI over the past 5 years.  This release either occurred inside an operating building and was too small to result in injuries or significant damage. 
 
Emergency Response Program 
 
Our emergency response program is based on the requirements in OSHA's emergency action and fire prevention plan regulation, OSHA's hazardous waste and emergency operations regulation, and EPA's emergency response program requirements in its RMP rule.  Our program consists of procedures for responding to a release of TDI.  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 requirements.  In addition, the plant has procedures that a 
ddress maintenance, inspection and testing 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 when necessary, based on modifications made to plant processes or other facilities.  Personnel affected by changes in the program are informed and or trained on those changes. 
 
The overall emergency response program for the plant is coordinated with the LEPC.  This coordination includes participation in periodic meeting of the committee, which includes local emergency response officials, local government officials, and other industry representatives.  The plant has around-the-clock communications capability with the appropriate LEPC officials and emergency response organizations such as the fire department.  This provides a means of notifying the public of an incident, if necessary, as well as facilitating quick response to an incident.  The plant also cond 
ucts periodic emergency drills that involve the LEPC and emergency response organizations. 
 
 
Planned changes to improve safety 
 
We strive to continuously improve the safety of our plant TDI process through periodic safety reviews and a program of soliciting safety suggestions from employees.  Our hazard review and incident investigation programs are especially designed to identify needed process safety improvements, some of which result in changes to the processes.  The following changes are currently planned for implementation: 
 
* Upgrade inspections and tests of selected equipment and instrumentation designed to prevent TDI releases 
* Revise operating procedures to resolve findings from the latest TDI process hazard review
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