Hershall B. Norred Water Treatment Plant - Executive Summary
SECTION ONE |
1.1 Executive Summary
The Federal Register/Vol.61, No. 120/Thursday, June 20, 1996 amended 40 CFR Part 68 to include the U.S. Environmental Protection Agency's (USEPA) Risk Management Program. This program requires facilities that have a regulated substance above the listed threshold quantities to develop a formal Risk Management Program (RMProgram) and to register and submit a Risk Management Plan (RMPlan).
The City of Newnan is subject to this regulation as the owner and operator of the Hershall B. Norred Water Treatment Plant located at 251 Water Works Road
Newnan, Georgia 30263. This facility is a stationary source of chlorine (a regulated substance) in excess of 2,500 pounds.
A RMProgram has been developed to meet the intent of the regulations for this facility using Program 2. Information from the Federal Register, AWWA's Compliance Guidance and Model Risk Management Program for Water Treatment Plants, and EPA's Risk Management Program Guidance For
Wastewater Treatment Plants (40 CFR Part 68) were used as resources for the development of this program.
The Hershall B. Norred Water Treatment Plant uses chlorine in its potable water treatment process to disinfect surface water obtained from raw water reservoirs. The chlorination process includes the storage of up to four (4) 1-ton cylinders of liquid/gaseous chlorine. The process is located within a closed building utilizing a vacuum feed system, instrumentation, process specific piping and connection materials.
A hazard assessment was conducted at the facility to determine the past history of accidents or releases of chlorine. Plant records and interviews with current plant personnel indicated there have been no releases of chlorine in the last five years that resulted in injury, death or property damage.
In compliance with the regulations, a worst-case release scenario was modeled using the EPA RMPComp dispersion model to determine the potential impact of such a release. The
worst-case scenario assumes that a one 1-ton container to releases 2,000 pounds of gaseous chlorine over a 10-minute period. The model predicted that areas within a 1.3 mile radius of the plant could be adversely affected by such a release. This area would include public receptors such as a school and private residences.
An alternative-case scenario was also modeled using RMPComp to model the effects of a more probable release. This scenario involved a valve failure resulting in the release of gaseous chlorine through a 5/16" diameter opening over a 60-minute period in a closed building. This simulation results in the release of 424 pounds of chlorine gas to the atmosphere. RMPComp predicted that areas located <0.1 mile from the release point could be adversely impacted. This scenario would only impact plant property and any employees who may be in the immediate area.
1.2 Overview of EPA Risk Management Regulations
The EPA Risk Management Program regulations are intended to preven
t and minimize the impacts of accidental releases of extremely hazardous substances. These regulations are applicable to the Hershall B. Norred Water Treatment Plant because chlorine stored at the facility is in excess of the EPA RMP Threshold amount of 2,500 pounds.
The Hershall B. Norred Water Treatment Plant RMProgram complies with the intent of the EPA regulations by providing information to the utility employees, local emergency preparedness officials, and the affected public to minimize health and safety impacts. The program consists of:
a. A management plan.
b. An employee participation plan.
c. A hazard assessment.
d. A prevention program (Program 2).
e. An emergency response plan.
f. Public Awareness, and
g. RMPlan submittal to EPA
A detailed listing of the EPA RMP regulations is not included herein; however, they are available at the EPA's home page: http:\\www.epa.gov\swercepp\.
The related Occupational Safety and Health Administration (OSHA) Process Safety Management (P
SM) rules (29 CFR 1910.119) require comprehensive management systems for the handling of these highly hazardous chemicals.
1.3 Goals and Objectives
The mission of the Hershall B. Norred Water Treatment Plant is to maintain public health by providing an adequate supply of safe drinking water, free of disease producing organisms and other health related contaminants. This process involves the addition of certain chemicals that, if released in an uncontrolled manner, may present a risk to public health. While such incidents are rare, they have occurred at other similar facilities. Based on a review of the EPA Accidental Release Information (ARIP) database, over 60 accidental releases of RMP regulated chemicals at water and wastewater treatment facilities in the USA were reported between 1986-1995.
State-of-the-art methods for reducing risks associated with utilizing highly mobile toxic chemicals, such as chlorine, have evolved in recent years. The newer risk management techniques consi
st of a comprehensive management system designed to promote responsible and disciplined operation, maintenance, and emergency response.
The overall goal in developing and maintaining the Hershall B. Norred Water Treatment Plant RMProgram is to reduce the risk to employees and the public of injury or death from the accidental release of chlorine liquid or gas. The RMProgram is not a substitute for other conventional health and safety programs.