Twin Lake Chemical, Inc. - Executive Summary
A. Accidental Release Prevention and Emergency Response Policies |
Twin Lake Chemical is committed to safety and the prevention of accidental releases of hazardous substances to the environment. The use of Phosgene, Chlorine and Phosphorus trichloride in our organic chemicals manufacturing facility is operated and maintained in a safe and responsible manner. We have implemented release prevention programs and emergency response policies in order to preserve and protect the health of employees. These programs and policies also serve as protection of human health and the environment of the communities surrounding Twin Lake Chemical.
B. Stationary Source and Regulated Substances
Our Lockport facility manufactures organic chemicals through the use of such regulated substances as phosgene (COCl2), chlorine (Cl2) and phosphorus trichloride (PCl3). COCl2 is supplied to the process from 1-ton DOT-51 cylinders for use as a reagent to make a variety of similar organic acids. Each acid ma
nufacturing process is completely separate, therefore only one cylinder or 2,000 pounds of COCl2 is part of a covered process at any time. We purchase PCl3 in bulk quantities and store it in a 3,500-gallon tank, where it is pushed with inert gas to the process. COCl2, Cl2 and PCl3 are the only toxic chemicals regulated under the RMP Rule by Part 68 that Twin Lake Chemical has on-site as part of a process. Twin Lake Chemical has no flammable substances regulated by Part 68.
C. Offsite Consequence Analysis Scenarios
It is a requirement of the RMP to model releases of our toxic substances as part of a hazard assessment. This hazard assessment must include one (1) worst-case release scenario and one (1) alternative release scenario for each substance involved in a process covered by the RMP Rule, regardless of the likeliness of the release.
The following brief summaries of each of these scenarios give the results of the modeling done using the EPA RMP Offsite Consequence Analysis
Guidance, and further give passive and active mitigation techniques that are in place to limit the feasibility of such a release to occur.
As mentioned above, Twin Lake Chemical has three (3) toxic substances covered by the RMP Rule: COCl2, Cl2 and PCl3
Worst-case Release Scenario - COCl2
The worst-case scenario for a release of phosgene is a complete failure of the 1-ton cylinder, therefore releasing 2,000 pounds in 10 minutes. The liquefied phosgene, at its vapor pressure and ambient temperature is assumed to immediately evaporate and be released to the atmosphere as a toxic gas. Passive mitigation is considered because the release would take place indoors. Therefore, we multiply the release rate by 0.55 to account for the enclosure. The scenario assumes rural conditions, F stability and a wind speed of 1.5 meters per second. The toxic endpoint of 0.00081mg COCl2 per liter of air reached a radius of 15.0 miles. Public receptors affected by this release are residences, severa
l schools, two hospitals, the county jail, public parks, and numerous area businesses.
Worst-case Release Scenario -Cl2
The worst-case scenario for a release of Cl2 is a complete failure of the 1,600-pound cylinder, therefore releasing 1,600 pounds in 10 minutes. The liquefied Cl2, at its vapor pressure and ambient temperature is assumed to immediately evaporate and be released to the atmosphere as a toxic gas. Passive mitigation is considered because the release would take place indoors. Therefore, we multiply the release rate by 0.55 to account for the enclosure. The scenario assumes rural conditions, F stability and a wind speed of 1.5 meters per second. The toxic endpoint of 0.0087mg Cl2 per liter of air reached a radius of 4.8 miles. Public receptors affected by this release are residences, several schools, a hospital, the county jail, public parks, and numerous area businesses.
Worst-case Release Scenario - PCl3
The worst-case scenario for a release of PCl3 is a complet
e failure of the storage tank therefore releasing 46,000 pounds. The liquid is assumed to instantaneously form a pool in the diked containment with a surface area of 651 square feet. The release rate to the atmosphere from this pool is calculated to be 33.7 pounds per minute. Based on a 60-minute release duration, and assuming rural conditions, F class atmospheric stability, and a wind speed of 1.5 meters per second, the toxic endpoint of 0.028 mg/L is reached at a radius of 2.1 miles. Public receptors affected by this release are residences, schools, hospitals, public parks, and businesses.
Alternative Release Scenario - COCl2
The alternate case or more-likely scenario for a release of phosgene is valve failure on the cylinder that would allow a maximum possible release of 2,000 pounds in 1 hour. The properties of chlorine are the same as above, however the plug valve on the cylinder can only release the entire contents of the cylinder in an hour as the maximum release. We fur
ther apply passive mitigation by multiplying the release rate by a factor of 0.55 because the release would occur inside the production building (enclosure). For the same toxic endpoint, the phosgene release will reach a radius of 9.3 miles, assuming rural conditions, F stability data and a wind speed of 1.5 meters per second. The public receptors located within this release radius include numerous residences, hospitals, schools, the county jail, pubic parks and recreation areas, businesses and major industrial sites.
Alternative Release Scenario - Cl2
The alternate case or more-likely scenario for a release of chlorine is a valve failure on the cylinder that would allow a maximum possible release of 1,600 pounds in 1 hour. The properties of chlorine are the same as above, however the plug valve on the cylinder can only release the entire contents of the cylinder in an hour as a maximum release rate. For the same toxic endpoint and taking into account the passive mitigation as ab
ove, the chlorine release will reach a radius of 2.7 miles. The public receptors located within this release radius include residences, parks and recreation areas, the county jail, some area businesses and major industrial sites.
Alternative Release Scenario - PCl3
The alternate case or more-likely scenario for a release of PCl3 is failure of the transfer piping between the tank and the process that has a material flow of 23 pounds per minute. For this scenario, it is assumed that the release would not last longer that 10 minutes. Because PCl3 is a toxic liquid, the release rate must be calculated to allow for evaporation of the liquid. The release rate to the atmosphere is calculated to be 3.7 pounds per minute and the 10-minute release reaches a distance of 0.74 miles in any direction. The release would affect area schools, businesses, and parks and recreation areas.
D. General Accidental Release Prevention Program and Chemical-Specific Prevention Steps
Our prevention progra
m follows the standard set forth by the Occupational Safety and Health Administration's (OSHA) Process Safety Management under standard 29 CFR 1910.119, and takes a proactive approach to preventing accidental releases of regulated substances that pose a danger to human health and the environment. Our program includes the following steps and programs that lead to successful accident prevention:
- Process safety information
- Process hazard analysis
- Operating procedures
- Mechanical Integrity
- Management of change
- Pre-startup review
- Compliance audits
- Incident investigation
- Employee participation
- Hot work permit
As part of our general prevention program, we have integrated chemical-specific prevention steps that help minimize the possibility of any leak of a hazardous substance that poses a potential danger both onsite and/or offsite. These steps greatly reduce risk:
Inspections - Regular inspections are performed on all p
rocess equipment to assure that the probability of failure is minimal. Through constant maintenance and careful monitoring of all operations and equipment, Twin Lake Chemical can prevent potential harm to employees and the surrounding environment by discovering an accident before it happens.
Personnel - Twin Lake Chemical maintains high standards for its employees in their ability to monitor and operate the onsite processes. Extensive training and experience in plant operations makes our employees our most important asset in maintaining safety onsite and preventing accidents.
Technology - Twin Lake Chemical uses advanced technology in its processes to automate and control precise process conditions. Further, this technology also monitors deviations in these process conditions that include leaks or that could produce a leak. Any deviations that could potentially result in a release are immediately corrected if possible or otherwise shutdown. We also have a monitoring system that
detects a release of either COCl2 or Cl2 in the process areas and sounds an alarm to alert employees.
Emergency Response - It is a vital part of Risk Management to minimize the effect that any release of a regulated substance could have on human health and the environment. We maintain an extensive response program for onsite accidents that pose a potential harm to employees and to offsite public receptors, including local residences. Our program keys in on stopping the release, getting the right people to the scene quickly, and notifying offsite public receptors that could possibly be affected. This plan is coordinated with the Lockport Fire Department, Public Dispatch (911), and the Niagara County LEPC.
These steps all coincide to manage the use of hazardous substances and prevent releases. Our facility is committed to its programs that minimize the potential for any accidents and releases of a hazardous substance. We strive to improve safety onsite at all times and operate at
or above our own high standards for safety.
E. Five-year Accident History
We are required by the RMP Rule to report all accidental chemical releases of regulated substances that meet or exceed the reportable quantity and keep them on-file as part of this Risk Management Plan. Further, we are required to keep on-file all accidental chemical releases that have occurred in the last 5 years.
As a result of Twin Lake Chemical's programs on safety and accidental release prevention, we have had no reportable releases in the past 5 years, as of June 20, 1994 involving substances covered under Part 68.
If such a release should ever occur, following the implementation of emergency response program procedures, a formal investigation will be conducted to identify and correct the cause(s) of the incident.
F. Emergency Response Program
In the event of an emergency situation, Twin Lake Chemical maintains a written emergency response plan to respond in an orderly, efficient and safe manner. Ou
r emergency response plan provides key background, planning and training for the handling of and responding to releases of regulated substances. The plan also defines procedures for proper notification of off-site public receptors in an emergency situation. Procedures for notification of local authorities with which our plan is coordinated are also given in the plan. The main objective involved in the implementation of this plan is the protection of workers, the public and the environment during emergency situations.
G. Planned Changes to Improve Safety
Twin Lake Chemical conducts Process Hazard Analyses (PHA's) that develop a list of suggestions for the improvement of process safety. These PHA's are performed every 5 years or when a process is changed, whichever comes first. The list of suggestions produced from the PHA is used to help improve safety for the employees, the pubic and the environment by reducing the risk of potential releases of regulated substances and emergency