Tar River Regional Wastewater Treatment Plant - Executive Summary

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 The accidental release prevention and emergency response policy: 
 
       The policy of the City of Rocky Mount is to manage hazardous chemicals in such a way as to prevent chemical releases and establish emergency response procedures to minimize the consequences of an accidental release at the Tar River Regional Wastewater Treatment Plant. The goal of this policy is to provide safe working conditions for employees as well as protect the public and the environment. 
 
The stationary source and regulated substances handled: 
 
     The subject source is the Tar River Regional Wastewater Treatment Plant located on Highway 97 East in Rocky Mount, North Carolina.  The facility is a 21 MGD pure oxygen activated sludge treatment facility serving Rocky Mount and surrounding communities. 
       
   The process at the wastewater treatment plant subject to the RMP regulations is the disinfection system, which manages greater than threshold quantities of chlorine and sulfur dioxide. 
 
The worst-case rel 
ease scenario(s) and the alternative release scenario(s): 
 
       Based on EPA criteria, the worst-case release scenario at the Tar River Regional Wastewater Treatment Plant is the catastrophic failure of a one ton cylinder used to store chlorine or sulfur dioxide resulting in an offsite impact.  EPA's "Risk Management Program Guidance for Wastewater Treatment Plants" was used for this determination.  This is extremely unlikely due to the safeguards described in the Prevention program. 
 
       The worst of the alternative release scenarios considered for chlorine is the catastrophic failure of the <-inch stainless steel tubing connecting the cylinder to the pipe manifold.  In order for the reported offsite toxic end point distance of 0.2 miles to be achieved, the cylinder's internal standpipe would also have to fail. There are numerous mechanical and procedural safeguards at the Plant designed to prevent this from occurring, however, for emergency response planning purposes they were 
not considered in the alternative release scenario. 
 
        The worst of the alternative release scenarios considered for sulfur dioxide is identical to that for chlorine. 
 
The general accidental release prevention program and chemical-specific prevention steps: 
 
       The accidental release prevention program at the Tar River Regional Wastewater Treatment Plant is focused on the safe management of chlorine and sulfur dioxide used in the disinfection system.  The first step in the prevention program at the Plant was the establishment of a management system to assign overall responsibility and responsibility for the individual program elements. Additional steps include: ensuring process safety information on the disinfection system is accurate, complete and up-to-date; ensuring the system is designed and modified safely by periodically conducting process hazard analyses; ensuring the system is operated and maintained in a safe manner by developing, maintaining and implementing Stan 
dard Operating and Preventive Maintenance Procedures; ensuring Plant employees are adequately trained and tested in the RMP program elements; ensuring new equipment and modifications to the disinfection system are designed, constructed, operated and maintained by following Management of Change, Pre-startup Review and Hot Work Permit Procedures; ensuring contractors are qualified, and oriented to the site hazards; and conducting periodic Compliance Audits and Incident Investigations including resolution of recommendations made during these investigations/reviews.  
 
The five-year accident history: 
 
       During the previous five years, no RMP chemical injuries related to the disinfection system have occurred at the Tar River Regional Wastewater Treatment Plant. 
 
The emergency response program:  
 
       The Tar River Regional Wastewater Treatment Plant is included in the City of Rocky Mount's Emergency Response Plan.  In addition, the Plant has in place an emergency action plan than in 
cludes procedures to be followed in the event of an accidental release of chlorine or sulfur dioxide.  The procedures cover the following: emergency action procedures; coordinating personnel; emergency reporting; evacuation plan; first aid procedures; notifying local emergency response agencies and the public; emergency response contacts; emergency response equipment; reportable release quantities; emergency alarm system; training and drills; and pre-emergency planning.
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