Scott Air Force Base - Executive Summary

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1.0 Introduction 
 
A Risk Management Program (RMP) has been implemented at Scott Air Force Base (AFB) for the reduction of accidental releases of hazardous materials. The RMP summarizes the management, administrative, procedural, and technological controls that work together to minimize the risk to the community from hazardous chemical releases. The Risk Management Plan is organized to correspond with specific U.S. Environmental Protection Agency (US EPA) RMP definitions and requirements, including: 
 
7 Introduction; 
7 Scott AFB policies to protect health, environment, and safety; 
7 Facility identification and regulated substances covered processes; 
7 Hazard Assessment; 
7 Prevention Program; 
7 Five-Year Accident History; 
7 Emergency Response Plan; and 
7 Planned changes to improve safety. 
 
2.0 Scott AFB Policies to Protect Health, Environment, and Safety 
 
The U.S. Air Force and Scott AFB have developed extensive programs for preventing and preparing for accidents involving hazardous mater 
ials.   As with all Air Force installations, Scott AFB is required to follow an extensive list of existing Air Force policies and procedures designed to protect human health and the environment.  The existing policies and procedures regarding the safe handling and storage of hazardous materials have been supplemented with a comprehensive Process Safety Management and Accidental Release Prevention Program for the Base.  
 
The chlorine processes at the base subject to the Risk Management Program are designed with extensive safeguards to protect against the accidental release of a hazardous material. The chlorine processes at the wastewater treatment plant are designed to operate under vacuum, which reduces the potential for a release to occur.   
 
In addition, process operators receive training in the safe operation of the process and are required to follow detailed operating procedures to help ensure safety.  Scott AFB also has implemented a mechanical integrity program to monitor the phy 
sical condition of process equipment, and replace or repair equipment before it fails. 
 
In the unlikely event of a spill or release involving a hazardous material, Scott AFB has a well-equipped and highly-trained base Fire Department. The Base Fire Department has received extensive training in the actions to be taken to safely respond to a release of hazardous materials, and maintains an extensive inventory of equipment for use in responding to a spill or release.  The Base has also developed a comprehensive disaster plan that provides detailed procedures to be followed in the event of an accident or emergency involving hazardous materials.  
 
3.0 Facility Identification 
 
Scott Air Force Base is located near O'Fallon, Illinois, approximately 20 miles east of St. Louis, Missouri.   The base's primary function is to provide medical transportation and care to Air Force personnel.  An on-base hospital provides medical treatment to Air Force personnel and their families. Approximately 10,000 
people are stationed and employed by the Base. 
 
Scott AFB has several processes and operations subject to US EPA's Risk Management Program regulations. The Risk Management Program regulations require facilities that store certain chemicals in excess of a threshold amount to prepare a comprehensive Risk Management Program.  The Risk Management Program requires facilities to evaluate the consequences of certain accidents involving hazardous chemicals, to prepare a comprehensive program to prevent accidental releases, and to have an emergency response program for taking action in the event of a release.   
 
The processes at Scott AFB subject to the RMP requirements include the following: 
 
7 Chlorine cylinder storage, and 
7 Wastewater Treatment Plant Chlorine Storage. 
 
4.0 Hazard Assessment - Worst Case Scenario (WCS) 
 
The worst case scenario for Wastewater Treatment Plant Chlorine Storage at Scott AFB would involve the failure of a chlorine cylinder at the wastewater treatment plant conta 
ining 2,000 lbs. of chlorine.  The chlorine would be released as a gas, and would form a vapor cloud that would travel in a downwind direction. For the worst case scenario, it was assumed that the entire contents of the vessel would release over a 10-minute time period. This would result in a release that would extend 1.3 miles to the endpoint. This scenario impacts residences, recreational areas and a school. 
 
5.0 Hazard Assessment - Alternative Release Scenario (ARS) 
 
Scott AFB evaluated an alternative release scenario involving a flashing liquid release resulting from a quarter-inch diameter hole in vessel.  In this scenario, the liquid chlorine flashes immediately to vapor and fine liquid droplets and is carried downwind.  The chlorine storage area at Scott AFB is contained within a permanent structure, therefore a 55% mitigation factor was taken into account.  Thus, the release of a flashing liquid from the 1-ton cylinder is assumed to occur as a result of the chlorinator (quarter 
-inch diameter) being sheered from the chlorine tank at the liquid level resulting in a loss to the surrounding room.  It was determined that the chlorine is then released from the room to the environment at a rate of 30 lb./min over a 10-minute time period.  This would result in a release of 300-lbs. that would extend 0.10 miles to the endpoint. This scenario impacts recreational areas on the base, but would not impact any homes or public facilities off-base. 
 
6.0 General Accidental Release Prevention Program 
 
A prevention program is in place to minimize the risk of hazardous chemical releases.  The prevention program provides a structured approach to preventing accidents. Some of the specific activities in the prevention program include: 
 
7 Process safety information is provided to all employees upon hire and is accessible at all times. 
7 In-depth process hazard analyses are completed every five years by qualified personnel using techniques approved under the PSM standard. 
7 Written  
operating procedures (kept up-to-date) are used for training and guiding the work of operators. 
7 Training is provided to all employees upon hire, and refresher training is given annually or upon request. 
7 Operators, mechanics, and contractor personnel are qualified, trained in the general hazards in the facility, and informed of any temporary situations affecting safety. 
7 Pre-startup safety reviews are conducted to insure that conditions for safe operation have been satisfied prior to starting new or modified equipment. 
7 A program is in place to maintain the mechanical integrity of the process, which includes written procedures, training requirements, equipment deficiency requests for employees, work orders, scheduled maintenance, and computerized documentation. 
7 A hot work permit system assures that work is done safely and properly. 
7 A management of change system is in place to ensure that changes are managed safely. 
7 Incidents are investigated and actions are taken as part of  
a continuous improvement effort. 
7 Routine audits are conducted to assure that safe practices are being followed. 
 
This systematic approach to process safety at Scott AFB involves employees and strives for continuing improvements in overall safety. The training, qualifications, and safety awareness of operations, maintenance, and management personnel are a key element in reducing and mitigating accidents. 
 
7.0 Five-Year Accident History 
 
There have been no accidents/releases of regulated substances from covered processes at Scott AFB that meet specific EPA criteria for the Five-Year Accident History. Such "RMP accidents" would involve serious accidents with on-site deaths, injuries, or significant damage; or known, off-site deaths, injuries, property damage, or environmental damage. Scott AFB realizes that the community may also be interested in smaller releases of regulated chemicals that do not meet such criteria. We have been diligent in reporting releases of hazardous materials and 
in internally investigating and correcting the causes of such releases. 
 
8.0 Emergency Response Plan 
 
Overall safety at Scott AFB is a function not only of programs to prevent accidental releases from occurring, but also of programs to mitigate the effects of accidental releases should they occur. Scott AFB has an emergency response program that is designed to protect lives, the environment, and property in the area. The Scott AFB Fire Department is staffed 24 hours a day, 365 days a year.  
 
At a minimum, all Fire Department response personnel at Scott AFB are trained to the Hazardous Materials First Responder Operations level. Several are trained to the Hazardous Materials Technician level and others to the Incident Command level. Scott AFB Fire Department personnel are responsible for the inspection, testing, and maintenance of all emergency response equipment on base. 
 
Scott AFB maintains a Spill Prevention Control and Countermeasure Plan (SPCC). Additionally, all buildings and are 
as develop Fire Prevention and Emergency Action Plans. Together, these documents delineate the responsibilities and interrelationships of the responding departments, describe their response capabilities, and provide incident-specific guidance in order to ensure timely resolution of an emergency incident.  
 
9.0 Planned Changes to Improve Safety 
 
Chemical safety is an important part of Scott AFB operations. The Health and Safety Committee as well as regulatory requirements have minimized chemical exposure risks to employees and the public through ongoing internal risk reduction efforts. For example, as a result of the Process Hazard Analysis (PHA), labels will be placed on all process vessels not currently labeled for easy identification.
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