Berea College Water Treatment Plant - Executive Summary |
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Accident Release Prevention and Emergency Response Policies at The Berea College Water Treatment Plant: The facility's chlorine water treatment process system was designed and installed to comply with recommendations of the Chlorine Institute, ASME standards and applicable NEC, NEMA, ASTM, and local building codes. Berea College's policy is to adhere to all applicable federal, state, and local laws. If an emergency were to occur, it is this facility's written policy and procedure to call the Berea Fire Department and notify the Madison County LEPC. Facility Description and Regulated Substance Discussion: The facility provides water for the city of Berea, Berea College, and customers in Southern Madison County. The facility stores chlorine in a maximum of four 1-ton chlorine cylinders. Typically, the largest volume of chlorine in storage at any one time is 6,000 pounds. Chlorine is used in the water treatment plant to supply up to 4 million gallons of water per day to the city o f Berea, Berea College, and customers in Southern Madison County. The system consists of a storage tank room, chlorine feed system, chlorine pressure monitoring system, water flow monitoring system, and a safety air monitoring system (for chlorine). Chlorine is an extremely toxic substance but the remote location of the facility reduces the likelihood of public risk in the unlikely event of a leak or spill. Worst Case Scenario: The worst case scenario which is extremely unlikely would be loss of 1-ton (2,000 pounds) of chlorine due to the rupture of the tank or complete failure of the piping system connected to the tank during a use or an unloading situation. This type of failure is identified by the American Water Works Association as the most likely "Worst Case Scenario" for a water treatment plant that has a 1-ton cylinder at service at all times. This failure would result in a spill of chlorine liquid that would immediately flash to vapor. The predicted offsite impact of 0.0 087 mg/L (toxic endpoint for chlorine) has a maximum radius of 2.2 miles and could potentially impact up to 3,104 people (as predicted from GIS mapping of 1990 census data). Alternative Case Scenario: Two alternatives considered were the loss of all of the chlorine in a full cylinder due to a slow leak over an 8 hour period (when the facility is unattended) and a minor release of the chlorine in the connection piping system during cylinder changeover. The predicted loss of 2,000 pounds of chlorine into the enclosed building over 8 hours would have a predicted impact of 0.1 miles. This impact is completely contained on the water treatment plant property. The predicted loss of 20 pounds of chlorine (10 pounds/minute for five minutes) from the piping system as a vapor cloud release would have an 0.0087 mg/L toxic endpoint of less that 0.1 mile (again no offsite impact). These predicted impacts would not affect any public receptor. General Accidental Release Prevention Program a nd Prevention Steps: The installation of the chlorine system was a result of the new water treatment plant installation in 1990. The facility installed the system according to recommendations by the Chlorine Institute, applicable standards, and applicable Federal, State, and Local code. Individual components of the chlorine delivery and feed system comply with NEC, NEMA, ASME, and Chlorine Institute recommendations. The chlorine storage and feed system is located in a locked room with a manual exhaust fan and vent that is used during staff entry into this location. The chlorine cylinders and delivered by PSB chemical and cylinder inspection, testing, and certifications are maintained by this vendor. Installation included the use of mechanical and electrical equipment specifically designed for chlorine service. A chlorine gas sensor is located in the chlorine storage room to alert staff of a release prior to entry to this room. This sensor has a remote alarm that sounds in the B erea College Central Steam Plant Control Room which is manned 24-hours per day. In addition to this alarm, there are numerous emergency system stop buttons located throughout the water treatment plant that permit the operator to immediately shut off the water supply and consequently stop the "on demand" chlorine feed system. All operators receive annual training to maintain their certification as water treatment system operators. Training is monitored by the Kentucky Public Safety Commission and the Kentucky Division of Water. Training consists of classroom training in the areas of safe system operation, water quality monitoring, routine water system monitoring and control, and general water treatment plant operation. Five-Year Accident History: There have been no major releases of chlorine from this process in the last five years that had any environmental impact. Emergency Response Program: The facility's policy is to immediately call the Berea Fire Department and the Madison County Local Emergency Planning Committee in the event of an emergency involving chlorine at this facility. The local responding agencies have reviewed the facility's system and the Berea College Water Treatment Plant plans to have these responding agencies conduct onsite awareness and inspection tours within the next few weeks. Planned Changes to Improve Safety: A Process Hazard Analysis is being conducted currently. The PHA should be complete by the end of July, 1999 with recommendations implemented on a priority basis for safety updates, training updates, procedure updates, and equipment/monitoring updates to be completed by November, 1999. |