Olathe Water Treatment Plant No. 2 - Executive Summary |
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PART 1: EXECUTIVE SUMMARY Introduction The City of Olathe operates two water treatment plant facilities. Water Treatment Plant No. 2 is a 17 million gallon a day lime softening plant. This Risk Management Plan (RMP) covers the Section 112r of the Clean Air Act regulating substances maintained at Water Treatment Plant No. 2, which will be referred to herein as the Plant. The Worst Case Release Scenario The worst case release scenario for chlorine was calculated as the loss of a single-ton cylinder in accordance with the definition provided in the Environmental Protection Agency guidance for RMP development. Only passive control systems were taken into consideration, such as the containment provided by the building. The conditions of the scenario, such as the release time and weather status are those provided in the EPA Off-Site Consequence Analysis Guidance. Determination of the area of potential impact was determined using RMP*Comp, modeling software developed by the EPA. The r esults of the Off-site Consequence Analysis indicated that the chlorine would travel approximately 11,620 feet under the specified weather conditions before dispersing in the atmosphere to a harmless concentration. Within that radius of the Plant, an estimated 615 people could be affected. Other than residential there are no additional potential receptors. Alternate Release Scenario The alternative release scenario is, by definition, a more likely release scenario than the worst case. Engineered controls, such as the chlorine detection system, the chlorine scrubber, and the cylinder block valves are considered in this analysis. The type of system failure selected for the alternative release was the loss of chlorine due to a break in the pressure piping. The chlorine would leak from a one inch line on the pressure piping. The leak would continue until the chlorine detector alarm sounded and the operator could respond to the alarm and shutoff the chlorine cylinder block valves without entering the building. The time estimated for this response would be 10 minutes. The results of the Off-Site Consequence Analysis using RMP*Comp, indicated that the chlorine would travel approximately 0 feet under the specified weather conditions in order to disperse in the atmosphere to a harmless concentration. No receptors were identified. Maps of the area and a list of the types of receptors in the potential impact area are provided in the Off-Site Impact Analysis Section. Process Hazard Assessment A process hazard assessment was performed of the chlorine system beginning with cylinder unloading and ending with the chlorine in solution. A combination checklist and modified "What-if" type of analysis was used. General questions regarding storage and use areas as well as practices and protocols associated with the management of the chlorination system were answered. A copy of the checklist is included in this plan. Following the checklist, the system was methodically assessed/evaluated from the cylinder to the point of chlorine injection using a system flow diagram. The valves and other points in the system where chlorine could be released are numbered on the flow diagram. The assessment is formatted in accordance with those numbers. Compliance with code requirements, considerations of potential failure, maintenance and inspection concerns, and standard operating procedures were reviewed for each point in the system. Comments are summarized in the Process Hazard Assessment section. Prevention Program The Plant has an operation, maintenance and inspection system designed to review each element of the chlorination system routinely. There are Operations and Maintenance manuals for each piece of major equipment, and personnel receive significant training before being allowed to work on the system. At the beginning of each of the shifts and as each cylinder is changed, the valves and piping are tested for leaks and checked visually. There are s tandard operating procedures (SOPs) for startup, shutdown, normal operation, and emergency operation. The SOPs are written and posted in the appropriate areas. Personnel are trained routinely on safety concerns and general operation procedures as well as emergency procedures. The system is equipped with chlorine detectors, a chlorine scrubber, and chlorine cylinder block valves to insure safe operation and protection. Continuous ventilation is provided when a worker is present in the room by means of a ventilation switch external to the room. Emergency Response Plan Plant personnel are allowed and trained to respond to leaks that can be managed by turning off a valve. Any response requiring entry in a dangerous atmosphere or use of a chlorine repair kit is to be managed by the Olathe Fire Department. The Plant has an agreement with the Fire Department. The City of Lenexa Fire Department will assist with a worker rescue only. A complete copy of the emergency plan and the Fir e Department Guidelines is included in this plan. Accident History The Plant has had no chlorine releases in the past five years. The new system with all of the additional safety features will insure the safety of the plant personnel as well as the surrounding area. |