ROCKY CREEK WPCP - Executive Summary

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                      EXECUTIVE SUMMARY 
Macon Water Authority maintains a Risk Management Plan for safe chlorine and 
anhydrous ammonia handling that involves an approach that integrates technologies, 
procedures and management practices to monitor potential hazards and minimize the risk 
of accidental release.  All applicable procedures of 40 CFR 68.170 are addressed in the 
plan, which seeks to provide for employee safety, public health and response agency 
Macon Water Authority utilizes chlorine to disinfect raw water pulled from the Ocmulgee 
River at the Riverside Water Treatment Plant and operations will begin at the Town Creek Water 
Treatment Plant sometime in the Fall of 1999.  Once operations at Town Creek are at the 
needed capacity the Riverside Water Treatment Plant will be closed.  Chlorine is also used at the 
Lower Poplar and Rocky Creek Wastewater Treatment Plants to treat wastewater before it 
is returned to the Ocmulgee River.  In addition, the Rocky Creek Pla 
nt also uses 
Anhydrous Ammonia to assist in treating wastewater.  Chlorination processes include 
(liquid) chlorination cylinders, chlorination equipment, and instrument room, electrical 
equipment, and process specific safety equipment.  Ammonia processes include (liquid) 
Anhydrous Ammonia above ground tanks, an instrument room, electrical equipment, and 
process specific safety equipment. 
For each chlorination process accidental release modeling was performed for the respective 
area to determine potential consequences associated with operating failures resulting in 
accidental chlorine release.  The first "worst case" scenario, defined by EPA, states that 
"the owner or operator shall assume that the. . . maximum quantity in the largest 
released as a gas over 10 minutes."  The "alternative scenario" is "more likely to occur than 
the worst-case release scenario."  Macon Water Authority has no incident history. 
In each case, atmospheric dispersion modeling was performed to det 
ermine the distance 
traveled by the chlorine released before its concentration decrease to a theoretical "toxic 
endpoint."  This is defined by the American Industrial Hygiene Association as "the 
maximum airborne concentration below which it is believed that nearly all individuals 
could be exposed for up to one hour without experiencing or developing life-threatening 
health effects."  The residential population within a perimeter corresponding to the toxic 
endpoint distance was defined to estimate the population potentially affected. 
The worst case release scenario for the Macon Water Authority Plants involves a failure of 
a one-ton cylinder yielding a cumulative release of 2,000 lbs of chlorine.  When atmospheric 
dispersion modeling for this unlikely scenario was performed using the RMP* Comp ver. 
1.06 a distance to toxic .9 miles urban and 2.2 miles rural was obtained.  The new Town 
Creek Plant presently under construction is the only plant located in a rural area. 
The alternative r 
elease (more likely) scenario for all chlorination processes involves tubing 
failure, bad connection, or valve failure resulting in the release of 317 lbs of chlorine.  
When atmospheric dispersion modeling for this scenario was performed using the RMP* 
comp Ver. 1.06 a distance to toxic endpoint of .1 miles urban or .1 miles rural was obtained. 
The worst case release scenario for anhydrous ammonia involves a failure of a 10,000 
pound tank yielding a cumulative release of 10,000 pounds of ammonia, when atmospheric 
dispersion modeling for this unlikely scenario was performed using the RMP* comp ver. 
1.06 a distance to toxic endpoint of .9 miles urban was obtained. 
The alternative release (more likely) scenario was performed resulting in a release of 10 
pounds/minute to a toxic endpoint of .1 miles. 
Macon Water Authority Risk Management Program includes the following key elements to 
mitigate the effects of potential chlorine release hazards: 
           Operator Training 
        Preventive Maintenance Program 
           Process specific safety equipment 
           Safe and effective standard operating procedures, written with operator                    
           Hazard review of equipment and procedures and 
           Auditing and inspection programs 
           Comprehensive Management Program 
Macon Water Authority has an active environmental, health and safety program with the 
following elements specifically supporting the safe handling of chlorine and the anhydrous 
ammonia processes.   
           Respirator protection (SCBA) program 
           Chlorine detectors, ammonia shut off valves 
           Chemical right to know program and 
           Personal protective equipment program 
Macon Water Authority plants have an emergency response plan, which has been 
coordinated with the City of Macon and Bibb County Fire Department which is a member 
of the Local Emergency Planning Committee (LEPC).  Emergency response dr 
ills, drill 
evaluations, and facility tours will be conducted annually, at which time emergency 
operation and response procedures are also reviewed. 
Macon water Authority takes a pro-active approach to risk management and emergency 
response through continuous joint training sessions between MWA employees and local 
response agencies.  These preventive measures will provide for the continuous improvement 
of communications and will maintain effective procedures for the safe handling of and 
timely emergency response to potential chlorine or anhydrous ammonia incidents.
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