Hazel Street Wastewater Treatment Plant - Executive Summary

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1.0    Accidental Release Prevention and Emergency Response Policies 
 
 
The City of Benton Wastewater Treatment Plant is committed to the safety of our workers, the public, and the environment.  This commitment is demonstrated by the resources invested in the prevention of accidental releases of hazardous substances.  The City of Benton Wastewater Treatment Plant implements reasonable controls, such as training of personnel and the safe design, installation, operation and maintenance of our processes.  Our policy is to make every effort to prevent the release of hazardous substance but in the event of a release, our trained personnel and local emergency response agencies will respond to control and contain the release in a manner that will be safe for workers and will help prevent injuries to the public or the environment. 
 
 
2.0    Description of the City of Benton Wastewater Treatment Plant and Regulated Substances 
 
 
The City of Benton Wastewater Treatment Plant is located within the city li 
mits of Benton, Arkansas, a city with a population of over 23,000 residents.  The facility treats 3 to 5 million gallons of wastewater per day.  The City of Benton Wastewater Treatment Plant handles one substance regulated by the Risk Management Plan Rule (RMP Rule) in quantities above the Threshold Quantity.  This substance is: 
 
* Chlorine - stored in 1 ton cylinders and used for disinfection of the wastewater prior to release into the receiving stream. 
 
In addition, the City of Benton Wastewater Treatment Plant uses sulfur dioxide in the treatment process.  Sulfur dioxide is a listed regulated toxic substance under the RMP Rule, but is not present above the sulfur dioxide threshold of 5,000 lb in the sulfonation process.  However, Section 112(r) of the Clean Air Act, which is the statutory authority for the RMP Rule, contains a General Duty Clause which requires sources producing, processing, handling, or storing any extremely hazardous substance to identify hazards which may resul 
t from releases of the substance using appropriate hazard assessment techniques.  The City of Benton Wastewater Treatment Plant has conducted a review of the sulfonation process consistent with the requirements of the General Duty Clause and has elected to pursue development of a Risk Management Program, including a Risk Management Plan (RMP) for sulfur dioxide.  Therefore, the sulfur dioxide storage cylinders and associated equipment will be considered a covered process for the RMP. 
 
 
3.0    Hazard Assessment 
 
 
The RMP Rule requires The City of Benton Wastewater Treatment Plant to perform a Hazard Assessment of the chlorine stored and used in the chlorination process at the facility.  This Hazard Assessment includes an offsite consequence analysis for the following scenarios: 
 
* One worst-case and one alternative release scenario for the toxic substance chlorine for the chlorination process unit at the facility. 
* One worst-case and one alternative release scenario for the toxic su 
bstance sulfur dioxide for the sulfonation process unit at the facility. 
 
The following information summarizes these offsite consequence analyses. 
 
3.1    Chlorination Process 
 
The worst-case scenario for toxic substances is the failure of a 1 ton cylinder of liquid chlorine.  The toxic cloud formed by the evaporating chlorine would reach off-site endpoints and public receptors. 
The alternative release scenario for chlorine is a cylinder valve sticking in the open position allowing a sixty minute release of chlorine gas.  The toxic cloud formed by the escaping gas would reach offsite endpoints and public receptors. 
 
3.2    Sulfonation Process 
 
The worst-case scenario for toxic substances is the failure of a 150 pound cylinder of liquid sulfur dioxide.  The toxic cloud formed by the evaporating sulfur dioxide would reach off-site endpoints and public receptors. 
The alternative release scenario for chlorine is a cylinder valve sticking in the open position allowing a sixty minute release of su 
lfur dioxide gas.  The toxic cloud formed by the escaping gas would reach offsite endpoints and public receptors. 
 
 
4.0    Accidental Release Prevention Program and 
   Chemical-Specific Prevention Steps 
 
 
The RMP Rule requires that a prevention program be established for the City of Benton Wastewater Treatment Plant chlorination and sulfonation processes.  The following details the prevention program elements at the City of Benton Wastewater Treatment Plant that apply to these processes. 
 
 
4.1    Safety Information 
 
The City of Benton Wastewater Treatment Plant maintains a variety of technical documents that are used to help ensure safe operation of the City of Benton Wastewater Treatment Plant processes.  Material safety data sheets (MSDSs) document the physical and chemical properties of hazardous substances handled at the City of Benton Wastewater Treatment Plant, including the chlorine and sulfur dioxide in the covered processes.  The engineering design documents include the operating para 
meters, the design basis and configuration of the equipment in each covered process, and references to applicable codes and standards. 
 
4.2    Hazard Review 
 
The City of Benton Wastewater Treatment Plant performs and periodically updates hazard reviews of the covered processes to help identify and control process hazards.  Checklists are used to guide the hazard review.  These checklists include items to help ensure the City of Benton Wastewater Treatment Plant operates and maintains the equipment in a manner consistent with the applicable design specifications, codes, standards, and regulations. 
 
4.3    Operating Procedures 
 
The City of Benton Wastewater Treatment Plant develops and maintains operating procedures to define how tasks related to process operations should be performed.  The operating procedures are used to: 
 
1. train employees and contractors, and 
2. serve as reference guides for appropriate actions to take during both normal and abnormal process conditions. 
 
4.4    Training 
 
The 
City of Benton Wastewater Treatment Plant trains personnel in the operating procedures to help ensure safe and effective performance of their assigned tasks. A record of all training is maintained to help ensure new and refresher training is provided on a timely basis. 
 
4.5    Maintenance 
 
The City of Benton Wastewater Treatment Plant properly maintains the equipment in our processes.  The City of Benton Wastewater Treatment Plant maintenance program includes: 
 
1. procedures to safely guide workers in their maintenance tasks, 
2. worker training in the maintenance procedures, and 
3. an inspection and testing program to help identify equipment deterioration and damage before equipment fails. 
 
 
4.6    Compliance Audits 
 
The City of Benton Wastewater Treatment Plant performs periodic (at least every three years) audits of covered processes to verify the processes are operating in compliance with the requirements of the RMP Rule.  A compliance audit report is prepared after each audit, and any d 
eficiencies noted by the audit are corrected in a timely manner. 
 
4.7    Incident Investigations 
 
The City of Benton Wastewater Treatment Plant investigates all incidents that could reasonably have resulted in a serious injury to personnel, the public, or the environment.  The City of Benton Wastewater Treatment Plant trains employees to identify and report any and all incidents requiring investigation.  An investigation team is assembled and the investigation is initiated within 48 hours of the incident.  The results of the investigation are documented, recommendations are resolved, and appropriate process enhancements are implemented. 
 
4.8    Chemical-specific Prevention Steps - Chlorine 
 
Industry standards are followed at The City of Benton Wastewater Treatment Plant to help ensure safe handling of chlorine.  The vendor supplies chlorine via a Department of Transportation (DOT) approved truck and in DOT approved 1 ton cylinders.  The chlorination process equipment is designed and construc 
ted with state-of-the-art materials and technology utilizing the standards and guidelines of the Chlorine Institute, Compressed Gas Association, American Water Works Association, ASME, ANSI, and other applicable codes.  Workers who perform operations involving chlorine receive training emphasizing safe handling procedures according to the guidelines required by the City of Benton Wastewater Treatment Plant. 
 
 
5.0    Five Year Accident History 
 
 
The City of Benton Wastewater Treatment Plant compiled a five-year accident history that fulfills the requirements of the RMP Rule.  This history indicates a good record of accidental release prevention over the past five years.  No releases of regulated substances have occurred from the City of Benton Wastewater Treatment Plant that have resulted in offsite consequences - injuries to the public or impacts on the environment.  Minor releases have occurred during loading and unloading procedures and maintenance activities with no injuries occurring  
to the City of Benton Wastewater Treatment Plant employees. 
 
 
6.0    Emergency Response Programs 
 
 
The City of Benton Wastewater Treatment Plant has prepared a written emergency response plan that complies with the RMP Rule, other federal standards and industry guidelines.  This plan has been communicated to the Local Emergency Planning Committee (LEPC) and local fire department.  The City of Benton Wastewater Treatment Plant periodically conducts emergency drills to test our emergency plan and coordinate these drills with the local fire department. 
 
 
7.0    Planned Changes to Improve Safety 
 
 
The City of Benton Wastewater Treatment Plant continuously attempts to improve the safety of our processes to protect our employee, the public and the environment.  The City of Benton Wastewater Treatment Plant incident investigations, employee suggestions and improvements in technology are utilized to update the safety aspects of the processes.  The following changes to improve process safety are plan 
ned or have recently been completed. 
 
1.  Implement a chlorine and sulfur dioxide shipment Quality Assurance Program to aid in the inspection of chlorine and sulfur dioxide cylinders when received, and 
2.  Implement a preventive maintenance program for the hoists used to move chlorine cylinders. 
 
 
 
 
 
 
June 4, 1999    1
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