Lafourche Parish Water District No.1- South Plant - Executive Summary |
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Lafourche Parish Water District No. 1 P.O. Box 399 Lockport, LA 70374 Risk Management Plan Executive Summary: South Treatment Plant 27713 LDEQ Facility ID Number The accidental release prevention and emergency response policies at your site Due to new regulations under the Chemical Accident Prevention Program, the District has developed a Risk Management Plan for chlorine gas. The requirements involve instituting a prevention plan to avoid unnecessary chlorine leaks in addition to revising its existing emergency response procedure. The expectations of the above mentioned requirements are to allow minimal injury and damage to occur, as well as to provide aid and guidance for other responders in the event of an accident. The prevention plan, developed by the District, has been designed to ensure that all precautions are taken so as to prevent and mitigate any possible chlorine release. One element of this plan is to assess the chlorine process for potential hazards that coul d contribute to a leak then correct the problems immediately. Another essential component is written operating procedures for all duties associated with chlorine, while another is to provide proper training to employees involved in those duties. From now on, all training and inspection information will be documented for future reference. The revised emergency response plan has been implemented with the intention that plant personnel will respond, contain and repair all chlorine leaks. One reason for this is because we feel our employees are properly trained and experienced enough to resolve the problem in a timely manner. Another reason is because plant policy allows chlorine cylinders to be handled only during normal working hours. Consequently most releases will occur at this time while enough qualified people are present to initiate a response. Nonetheless, it is possible to have a release after hours, but because two people are on site at all times they will be able mitigate the situation. Your Facility and the Regulated substance handled. 1. Location of Facility: The Lafourche Parish Water District No. 1 - South Treatment Plant is located on LA Highway 308 just north of Lockport. The physical address is 5753 Highway 308, Lockport. 2. Background Information: The Lafourche Parish Water District No. 1 - South Treatment Plant is a potable drinking water production facility. The District purifies water taken from Bayou Lafourche and distributes the water to customers throughout Lafourche Parish. Chlorine gas is used as a disinfectant in the treatment process and is fed continuously. The District has one (1) ton and one hundred fifty (150) pound chlorine cylinders on site. Plant personnel remove the one (1) ton cylinders when empty and replace them with full cylinders. This involves transporting cylinders with a forklift, lifting the cylinders with a hoist, and mounting a regulator onto the cylinder valve. These chlorine cylinders are only replaced during normal working hours due to safety concerns. District personnel can deal with most emergency response and repair situations; nonetheless, outside assistance may be necessary depending on the severity of the leak. "A" and "B" repair kits, self-contained breathing apparatuses, and extra air bottles are stored in an emergency response and repair cart, which is available for quick response. Containment suits and gloves can also be found in the cart. Sugarcane and pastureland surround the plant on three sides with LA Highway 308 on the other. The closest residence is located across Bayou Lafourche approximately 900 feet west of the plant. The Worst Case scenario and the Alternative Case scenario 1. Worst Case Scenario The worst case scenario for a chlorine gas release is when the total content of a one ton cylinder is expelled within ten minutes. In this event, the total quantity released is 2000 pounds with the release rate being 200 pounds per minute. The variab les used in determining the distance that the gas travels is an urban topography, an F-stability class (atmospheric conditions), and a wind speed of 1.5 m/s. When these conditions exist, the toxic endpoint is 5.4 miles according to the look up tables in the "Offsite Consequence Analysis Guidance" model. The population affected by this scenario is approximately 7,198 people all within Lafourche parish. No environmental receptors would be affected in such a case; however, schools, recreational areas, businesses, residences, and a hospital are within the 5.4 mile endpoint. For this reason it is crucial that extreme precautions be taken to prevent this from ever occurring. 2. Alternative Case Scenario The most likely case scenario of a chlorine gas release for Lafourche Parish Water Dist. #1 is a malfunctioning valve on the cylinder itself. When a chlorine cylinder is put into service, the valve is never open more than <" which is approximately 0.05 square inches. Using this inf ormation, the release rate of a jammed valve is calculated to be 9.63 pounds per minute (information acquired from chlorine supplier). Because this scenario will tend to occur during normal working hours, as explained above, the time taken to repair the leak will be minimal. It is estimated through drills that it takes approximately ten (10) minutes to repair a leak such as this. Accordingly, a fifteen (15) minute release at 9.63 pounds per minute allows 145 pounds of chlorine to be expelled. The variables used in determining the distance that the gas travels is an urban topography, an F-stability class (atmospheric conditions), and a wind speed of 1.5 m/s. When these conditions exist, the toxic endpoint is 0.31 miles according to the look up tables in the "Offsite Consequence Analysis Guidance" model. The population affected by this scenario is approximately 24 people all within Lafourche parish. No environmental receptors would be affected in such a case, however businesses an d residences are within the 0.31 mile endpoint. For this reason it is crucial that extreme precautions be taken to prevent this from ever occurring. The general accidental release prevention program and chemical-specific prevention steps. 1. General: The following information represents general prevention program improvements to prohibit unnecessary chlorine leaks. 1) Safety information documented and distributed to employees 2) Properly designed chlorination equipment 3) Hazard review conducted 4) Written operating procedures 5) Periodic training (equipment, safety, leak repair) 6) Regularly scheduled maintenance 2. Specific: The following information represents specific prevention program improvements to prohibit unnecessary chlorine leaks. 1) Area chlorine leak detectors with alarm. 2) Personnel make general observations of the chlorine process every half-hour to ensure conditions are normal. 3) All chlorine cylinders are inspected upon delivery. 4) The following written o perational procedures are provided to each employee. Receiving chlorine cylinder shipments Transporting cylinders Changing cylinders 5) Continuous hands on training for mounting chlorination equipment given by supervisors. 6) A supervisor and two other plant employees always on site while chlorine cylinders are changed. 7) The chlorine room is kept clean and free of excess traffic with all tubing neatly positioned out of the way. The Five year accident history The Lafourche Parish Water District has not had a chlorine release in the past five years. We feel this is due to having employees who are well trained and very competent in the duties in which they are involved. The Emergency Response Program As mentioned, the goal of our emergency response program is to effectively respond to chlorine leaks allowing minimal injury or damage to occur. It will also aid other emergency response personnel by providing guidance in the event of an accident. Some of the elements of this plan are referenced to below. 1. Alarm: One method of determining that a leak has occurred is by the chlorine leak detector alarm, while another is by general observation. This chlorine leak detector sounds an alarm when elevated chlorine levels are found. It continues for the duration of the abnormal concentrations; consequently the alarm will not silence until the chlorine leak is repaired. If concentrations are not high enough to trip the alarm, the leak should be minimal; therefore, an employee may find a leak before the leak detector does. In any case, all plant personnel should immediately report to the primary assembly area, which is the lab/control room. If it is inaccessible, they should then report to an area in the yard that is upwind of the leak. There, all other personnel shall be notified of the situation, and a code response will be initiated. 2. Overall Emergency Response Coordination: After gathering as much information as possible from the staff, the Ranking Super visor will be responsible for coordinating the emergency response. He will have to manage the following: 7 Determine the severity by information gathered and initiate a code response. (Code "Yellow" or "Red") 7 Notify all employees on site of leak via telephone and intercom. 7 Make sure all personnel are accounted for. 7 Appoint duties to available personnel. 7 Determine the need to notify appropriate agencies for outside response assistance (greater than 10 pounds released). Until state police responders arrive, the ranking supervisor will continue to command the response. 3. Code Response: There are two levels used to respond to a chlorine leak, a Code "Yellow" and a Code "Red". The code yellow response will normally be initiated for small leaks (less than 10 pounds) and unknown leaks. This situation may or may not require the emergency response cart, but it will be prepared for use regardless. The code red response will be utilized when a leak is known to be large (grea ter than 10 pounds) and/or repair kits are needed. The decision to initiate either response will be at the discretion of the ranking supervisor. If after hours, the person on site and the ranking supervisor who is notified will decide on whether outside assistance is needed. 4. After Hours: If an emergency situation arises after hours, the man on standby and any other supervisor available will be contacted and notified of the situation. The workers on site and the ranking supervisor will use their discretion for calling on outside assistance, nonetheless, specific agencies will be notified if the leak exceeds ten (10) pounds. While waiting for help, the two men will shut down the plant if necessary and prepare the emergency repair cart for use. 5. Outside Assistance: When outside assistance is needed in an emergency response situation, 911 will be called. Detailed information of the situation will be given, including wind direction and the designated assembly area. Depending on available personnel, someone will meet the responders at the front gate to update the situation and direct them to the response. If outside assistance is needed, the chlorine leak will most likely be larger the ten (10) pounds. Therefore, the following list of agencies will be notified immediately. 911 State Police (225) 925-6595 Laf. Parish Emerg. Planning Comm. (504) 446-8427 Laf. Parish Fire Department: 911 Laf. Parish Sheriffs Office: 911 Chem Trec (800) 424-9300 National Response Center (800) 424-8802 Dept. of Environmental Quality (504) 532-6206 6. Shelter / Evacuation: A decision as to evacuate or to shelter in place will be made by the ranking supervisor at the time of the incident. Generally, a major chlorine release will last at most, 30-40 minutes, therefore shelter in place will more than likely be used in an emergency situation. Nevertheless, personnel will be prepared to evacuate the premises on short notice. Evacuation will be utilized if there is a massive quantity of chlorine released or if the wind direction requires it. 7. Public Notification: When outside assistance is required, the fire department, sheriff's office, and the local emergency planning office will be informed of the situation. Together a decision will be made on whom to notify. The most likely case will require sheltering residences within = mile of the plant for precautionary purposes. As a result residences will be asked to shut windows, close any ventilation system, and listen for further advisories. 8. Emergency Treatment: A section in the emergency response plan is designated for emergency treatment for victims for chlorine exposure. This information includes basic first aid tips as well as complex medical advice for health professionals to reference. 9. Response and Repair Training Chlorine leak repair training will be conducted a minimum of every other year, but is generally held yearly. Also, drills are periodically performed to familiarize employees with an emergency situation. Planned Changes to Improve Safety As seen in the above worst case scenario, no passive mitigation was taken into consideration. The reason is because the chlorine cylinders stored for inventory are kept outdoors. By the end of 1999, a new chlorine storage building shall be constructed, therefore allowing less of the community to be affected. Also, an improved system of documenting chlorine process information has been developed. Other than this, the changes were minimal. |