MCB Camp Pendleton - Executive Summary |
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MCB Camp Pendleton (Base) is the United States Marine Corps' largest amphibious assault training facility. The Base covers an area of approximately 125,000 acres and is populated by over 40,000 military personnel and civilian employees in addition to numerous military dependents. The Base provides its own water supply and wastewater treatment facilities within its boundaries. Disinfection is therefore necessary to reduce the potential for transmission of infectious diseases. Chlorination has long been the accepted and preferred method of disinfection for both water and wastewater in the United States. The same properties that make chlorine valuable as a disinfectant also make it necessary to observe certain safety precautions to prevent unnecessary human exposure during handling and, to protect the health of persons on MCB Camp Pendleton and in the surrounding communities. 1.1 ACCIDENTAL RELEASE PREVENTION AND EMERGENCY RESPONSE POLICIES Accidental release prevention for the MC B Camp Pendleton systems is dependent on developed chlorine handling procedures, safety devices inherent in the design of the facilities, and staff training. Base facilities have been assessed against the National Fire Protection Association (NFPA) Standard 55 - Storage, Use and Handling of Compressed and Liquefied Gases in Portable Cylinders, and it is Base policy to adhere to all applicable federal, state, and local laws. The chlorine system is enclosed in a locked building and access is restricted to authorized employees and contractors. Building 20831 is clearly signed "Danger Chlorine" to reduce unauthorized entry. An Emergency Response Program has been developed to respond to both worst-case and alternative release scenarios. The emergency response actions involves system operators and maintenance staff, the Base Fire Department, and off-site expertise from the San Diego County Hazardous Incident Response Team (HIRT), when necessary. In addition, the Assistant Chief of Staf f, Environmental Security (AC/S, Environmental Security) serves as the focal point for notifying the appropriate agencies and providing information to the public. The accidental release protection for the chlorine systems also involves a prevention program that includes: 7 Documenting process safety information 7 Conduct a process hazard analysis 7 Using operating procedures 7 Implementing a maintenance program 7 Conducting incident investigations 7 Conducting compliance audits 1.2 STATIONARY SOURCE AND REGULATED SUBSTANCES HANDLED Building 20831, Sewage Treatment Plant (STP) 13, houses two (2), one-ton containers on-line and five (5), one-ton containers in storage for a maximum amount of 14,000 pounds. Chlorine is used at this facility for wastewater disinfection. 1.3 WORST-CASE RELEASE SCENARIO(S) AND ALTERNATIVE RELEASE SCENARIO(S), INCLUDING ADMINISTRATIVE CONTROLS AND MITIGATION MEASURES TO LIMIT THE DISTANCES FOR EACH REPORTED SCENARIO U.S. EPA regulations require M CB Camp Pendleton to conduct an off-site consequence analysis to provide information to the public and government agencies about the potential consequences of an accidental chlorine release. The offsite consequence analysis (OCA) consists of two elements: 7 Worst-case release scenario 7 Alternative release scenario 1.3.1 Worst-Case Release Scenario U.S. EPA regulations require the evaluation of a worst-case release scenario consisting of a release from the largest vessel in the system over a ten minute period under conservative weather conditions. Therefore, an analysis was made of the entire contents of an one-ton container releasing a rate of 200 pounds per minute, under weather condition prescribed by the U.S. EPA as Class F stability and wind speed of 1.5 meters/second. The release conditions were evaluated to determine the distance away from the systems where a maximum airborne concentration of 0.0087 mg/l (3 ppm) would exist. This airborne concentration has been determine d by the U.S. EPA as the "toxic endpoint" below which it is believed that nearly all individuals can be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms which could impair an individual's ability to take protective action. The distance to the endpoint of 0.0087 mg/L (3 ppm) for the worst-case scenario is dependent on the topographic setting (i.e., urban or rural) for the process. Building 20831 is located in an urban setting and has a toxic endpoint distance of 1.3 miles. An evaluation of this distance determined that several public receptors, offsite impacts, are likely to be affected during this worst-case release scenario. 1.3.2 Alternative Release Scenario The selected alternative involves mechanical failure of a fusible plug. As a safety relief device, 1-ton chlorine containers have six fusible metal plugs, three on each end, spaced 120: apart. Assuming a scenario where the malfunctioning plug is loca ted in the lowest position (closest to the ground), a liquid chlorine release could result. Based on U.S. EPA's Risk Management Program Guidance for Wastewater Treatment Plants (October 1998), a 0.3-inch opening would result in a release rate of 240 lbs/min and an endpoint distance of 0.3 miles. The more common weather conditions of Class D stability, 25: Celsius (77: Fahrenheit) temperature, and wind speed of 3.0 meters/second are assumed for the alternative scenario. Evaluation of the alternative zone of vulnerability for Building 20831 indicates that public receptors could be impacted. 1.4 GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM AND THE SPECIFIC PREVENTION STEPS MCB Camp Pendleton has taken steps so that the chlorine systems comply with U.S. EPA's Accidental Release Prevention Rule and with applicable state codes and regulations. Building upgrades are being planned or considered for Building 20831 and are described in Section 1.7. MCB Camp Pendleton has developed a prevention program that includes: 7 Documenting process safety information regarding the hazards of chlorine and components of the system. 7 Conducting a process hazard analysis to evaluate potential mechanical failures or operational causes that could result in an accidental release 7 Implementing a standard operating procedure 7 Implementing a mechanical integrity program 7 Conducting incident investigations 7 Conducting compliance audits 7 Implementing Management of Change Procedures 7 Conducting a pre-startup review 7 Implementing an employee participation program 7 Implementing an employee training program 7 Implementing a contractor safety program 1.5 FIVE-YEAR ACCIDENT HISTORY According to information provided by the MCB Camp Pendleton Fire Department and AC/S, Environmental Security, since June 21, 1994, or the date of construction of the system if later, there have been no accidental releases from facility 20831 that resulted in injuries to public receptors, or response or restoration activities at an environmental receptor. 1.6 EMERGENCY RESPONSE PROGRAM The Emergency Response Program is based upon the existing management system for responding to emergencies, the appropriate discovery and notification procedures, and coordination with the San Diego County Hazardous Incident Response Team (HIRT). The operators and maintenance staff for the Facilities Maintenance Department (FMD) have been trained as Facilities Responders to report accidental releases to the Base Fire Department. The Base Fire Department subsequently notifies HIRT for emergency response actions. The AC/S, Environmental Security plays an active role in notifying the appropriate government agencies and communicating releases to the public. 1.7 PLANNED UPGRADES TO IMPROVE SAFETY Upgrades to improve the safety of several of the Program Level 3 chlorine systems are being considered or planned at the time of this document's initial preparation and submittal. Upgrade of the chlorine leak detection at facility 20831 is scheduled for 1999. Other changes proposed as a result of the compliance audit are scheduled for June 1999 and when the next chlorine vendor's contract is renewed. |