Smyrna Water Treatment Plant - Executive Summary

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The accidental release prevention and emergency response policies at our facility.  The Town of Smyrna Water Treatment Plant is committed to the use of safe procedures and prevention of chemical releases.  Our emergency action plan applies to the use of chlorine in the water treatment process a the Town of Smyrna Water Treatment Plant.  The purpose of the plan is to aid the Town of Smyrna in its efforts to prevent or mitigate episodic releases of chlorine that could result in the catastrophic loss of personnel and property within the facility and possibly the surrounding community. 
 
Our Facility.  The Smyrna Water Treatment Plant utilizes chlorine as its primary disinfectant in the process of treating drinking water.  The chlorine is stored in a building approximately 100 yards from the main admistration and operations building.  The building usually contains 10 tons of chlorine.  The building is enclosed and with the only possible leaks occuring at the cylinder.  The room has constant 
video monitoring and a chlorine scrubber along with constant air monitoring of the room for chlorine.  This chlorine monitor activates the scrubber and sounds an audible alarm and sets off alarm lighting. 
 
Chlorine presents physical properties and health hazards that would present immediately dangerous to life and health (IDLH) conditions in the event of an uncontrolled release gas.  The following section consists of a review of the inherent physical and health hazards associated with chlorine for emergency response personnel. 
 
Physical Properties 
 
a.  At room temperatures, chlorine is a gas. 
b.  If chlorine is cooled to 29.3 degrees F, it becomes an amber color liquid.  It is usually shipped as a liquid in order to save space. 
c.  If liquid chlorine escapes from a container it will usually be boiling and convert to a greenish-yellow color gas. 
d.  It has an irritating odor (bleach) and is 2 = times heavier than air, so it will usually gather low to the ground. 
e.  Chlorine is soluble 
in water, but reacts with water to form hydrochloric acid, which is highly corrosive. 
f.  NFPA has assigned a hazard rating for chlorine of: 
             Health - 3     Flammability - 0      Reactivity - 0      Special Hazard - Oxidizer 
 
Health Hazards 
 
a.  The minimum detectable odor level of chlorine for most individuals is 0.3 ppm.  Chlorine will cause irritation of the upper respiratory system and mucus membranes at 3 to 6 ppm. 
b.  The TOSHA permissible exposure limit for chlorine is represented by a ceiling value of 1 ppm.    NIOSH has assigned an IDLH value of 10 ppm for acute chlorine exposure. 
c.  Exposure to exposed skin or eyes can cause serious frostbite burns. 
d.  Inhalation of chlorine gas can lead to adverse acute health effects including:  irritation of the upper respiratory system, violent coughing, choking, nausea, dizziness, headache, vomiting, chest pains, shortness of breath and pulmonary edema. 
 
Worst Case Senario.  Chlorine is dropped during loading/unloading/ha 
ndling, resulting in the rupturing of the cylinder or valve stem and the uncontrolled release of the contents of the cylinder.  Fire in or near chlorine room allowing the fusible plug to melt in cylinder or a faulty fusible plug. 
 
Alternate Senario.  The yoke on the cylinder valve is defective, malfunctions or is improperly installed onto a chlorine cylinder,  resulting in the limited yet uncontrolled release of gas from the cylinder. The valve packing leaks from a defective chlorine resulting in the limited yet uncontrolled release of gas from the cylinder. The yoke is not properly set and tightened on the cylinder valve. The yoke was not properly cleaned with the wire brush prior to installing the washer. 
 
The general accidenall release prevention program and chemical-specific prevention steps. 
 
FIve year accident history.  We have only had four accidental releases in the past 5 years with the largest release being about 5 lbs.  No one on-site or off-site was injured and there was no 
damage to property. 
 
The emergency response program. Chlorine Release Hazard Control Measures. Engineering controls, administrative controls and personal protective equipment are used to mitigate the hazards associated with the release of chlorine gas.  These hazard control measures were developed and implemented to increase the effectiveness of the emergency response actions and protect emergency response personnel and the public. 
 
    Engineering Controls 
 
       * Fixed Chlorine Monitor 
 
        -A fixed chlorine monitor is located in the chlorine cylinder storage room.  The monitor will detect       
         chlorine at 0 to 5 ppm.  The chlorine monitor is connected to the SCADA system to obtain constant 
         readings from the control room. 
 
         *Personal Chlorine Monitor 
 
         -Portable, personal monitors for chlorine are available for use during response to gas release  
          episodes.  The monitors will provide quantification of gas contaminant levels w 
hich can be utilized 
          to  determine the type of personal protective equipment deemed necessary and zones for   
          evacuation purposes. 
 
         *Ammonia Solution Leak Testing 
 
         -Use an ammonia solution to check for leaks within the chlorine process piping or valves.  This is 
          done by discharging ammonia vapor in the area of a suspected leak.  If a chlorine gas leak is 
          present, a whitish cloud will form. 
 
         *Emergency "B" Kit 
 
         -An Emergency "B" Kit contains devices to stop leaks at the valves, fusible plugs and in the wall of  
          one-ton cylinders.  This Kit is located outside the chlorine room. 
 
      Administrative Controls 
 
         *Training of Emergency Response Team Members 
 
         -Emergency Response Team Members will receive 24-hours of Hazardous Materials Technician 
           training, which fully complies with the requirements of TOSHA 1910.120 (q) (6) (iii).  The training  
          provides c 
lassroom instruction, demonstrations and hands-on application of appropriate response 
          actions for anticipated chlorine release episodes. 
 
         *Process Safety Management Training 
 
         -Facility personnel handling chlorine cylinders, performing maintenance on the chlorine system and 
          operating the system are involved in the Smyrna Water Treatment Plant PSM program and receive 
          training which fully complies with the requirements of TOSHA 1910.119 (g) (1). 
 
         *Buddy System 
 
         -Handling (loading/unloading) of cylinders and maintenance on the process system require the  
          presence of a minimum of two workers at all times. 
 
         *Daytime Cylinder Handling 
 
        -Cylinders are only handled during the daytime.  This safeguard was implemented due to the potential 
         for catastrophic consequences if a cylinder were to fall and rupture, and the difficulties which could 
         be associated with attempting to res 
pond to a potential catastrophic release of chlorine during the  
         night time. 
 
        *Process Safety Management Program Manual 
 
        -A site-specific PSM Program Manual has been developed and implemented for the Smyrna Water 
         Treatment Plant Facility.  The PSM Program Manual provides identification and evaluation of potential 
         chlorine release scenarios and a review of the safeguards in place to mitigate the catastrophic  
         consequences of a chlorine release. 
 
    Personal Protective Equipment 
 
        *Respiratory Protection Equipment 
 
        -Respiratory protection equipment consists of three Self-Contained Breathing Apparatus (SCBA)     
         backpack units (SCOTT 2.2).  Four SCBAs are located at the High Service Pump Station.  These  
         SCBAs will be used in atmosphere containing in excess of 3 ppm.  Each employee of the Smyrna  
         Water Treatment Plant is issued one SCOTT full-mask respirator with acid gases cartridge 
s (suitable  
         for chlorine up to 10 ppm) which will be used on in atmospheres of 0 ppm to 5 ppm. 
 
Planned changes to improve safety.  Continue to provide training annually to personnel and practice repairs and chlorine safety.
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