Washington Booster Pumping Station - Executive Summary |
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RISK MANAGEMENT PLAN - WASHINGTON BOOSTER PUMPING STATION EXECUTIVE SUMMARY Eastern Municipal Water District (EMWD) has established a risk management plan according to EPA's regulations (40 CFR Part 68) to enhance already existing safety and emergency response programs. EMWD is extremely cautious in the handling of all chemicals and is very diligent about safety for its employees and its communities. EMWD staff is highly trained and utilizes modern equipment to monitor its facilities to provide safeguards, while effectively employing these useful chemicals. These chemicals play an important role in water treatment and water reclamation, enabling everyone to lead healthier lives. Accidental Release Prevention and Emergency Response Policies EMWD has an emergency response plan in effect to handle potential emergency situations at this facility. This plan was designed to meet the following objectives: 1.) To save lives. 2.) To minimize and avoid injuries. 3.) To protect the environ ment. 4.) To minimize property damage. The Eastern Municipal Water District Safety Officer is the designated emergency coordinator for the facility. The District also maintains an on-call Emergency Response Team. The Plan provides the response organization and notification procedures, evacuation routes, chlorine health hazards and mitigation procedures which will be implemented to respond effectively to emergency situations that may arise at the facility. This Plan is reviewed and updated at least once per year and has been reviewed and updated to ensure compliance with the PSM, RMP and CalARP regulations Stationary Source and Regulated Substance The chlorine system at Washington Booster Pumping Station is used for the treatment of potable water. This is an unmanned facility. An operator visits the site at least once per week. If maintenance on the chlorine is required, two operators/maintenance personnel are present. Chlorine is stored in one-ton containers in the chlorine s torage room. The maximum number of ton-containers that may be present in this room is six. These containers are owned, maintained and filled by the chlorine chemical vendor per Department of Transportation regulations and standards. Two ton-containers are placed on a scale to allow EMWD operators to plan ahead for ordering more chlorine and for the change out procedure. Each container is positioned so that the valves are vertically aligned. A vacuum regulator is connected to the top valve of each one ton container to ensure that chlorine gas is drawn out of the container. A vacuum is created when process water is pumped through the injectors. This flow generates a vacuum (approximately 1-3 in. Hg) which opens the vacuum regulator. Upon loss of vacuum in the line from any one ton container, a diaphragm in the vacuum regulator will close, stopping any chlorine from escaping. Any chlorine in the piping upon loss of vacuum will be drawn through the chlorine feeders and into solut ion. A chlorine scrubber is connected to the chlorine building. Its sole function is to remove chlorine gas from the room in case of an accidental release from the system. The scrubber is automatically activated by the chlorine detectors that are installed in the room. At 1ppm the detector sounds an alarm in the central control room of EMWD and at 3 ppm the scrubber system is activated. In the scrubber, the chlorine gas is reacted with sodium hydroxide. The result of which is water and table salt. Hazard Assessment Summary Worst Case Release Result Summary Scenario Description: Release of the maximum quantity of chlorine that can be stored in the largest vessel - 2,000 pounds in 10 minutes. The container is located in a building; therefore, this passive mitigation measure was incorporated in the calculations. The most pessimistic meteorological conditions were used as specified in the regulation. The reference table included in EPA's RMP Guidance for Wastewater Treatment Plants was used to determine the maximum downwind distance to 3 ppm. The result shows that offsite areas may be affected. Alternative Release Result Summary Scenario Description: A release of chlorine gas from 1/4-inch diameter leak until the container is empty (2,000 pounds). The containers are stored inside a building equipped with a scrubber, which will automatically start in the event a chlorine leak is detected by the sensor. However, when these active and passive mitigation measures were incorporated the release is completely mitigated, consequently, the release rate after these measures were incorporated was too small to measure. The meteorological conditions specified in the regulation for alternative scenarios were used. Assuming that the scrubber is not functioning, the reference table included in EPA's RMP Guidance for Wastewater Treatment Plants was used to determine the maximum downwind distance to 3 ppm. The downwind distance for this scenario is significantly les s than that for the worst case scenario. However, in this case also, assuming that the scrubber is not functioning, offsite areas may be affected. Accidental Release Prevention Program and Chemical-Specific Prevention Steps EMWD has a Process Safety Management program in place to manage the handling of chlorine. In addition, common industry standards, policies, and procedures are utilized to ensure safe practices are being performed. This includes common practices outlined by the Chlorine Institute. In addition to the Management Programs, there is a chlorine leak detector situated in the chlorination building. In the event of a chlorine gas leak reaching 1 ppm, the detector relays an alarm to the central control station of EMWD. At 3 ppm, the alarm signal actuates the emergency scrubber system for the chlorination building. Five Year Accident History There have been no reportable releases of chlorine at the facility in the past 5 years. Planned Changes to Improve Safety S everal process and management system improvements were implemented during the development of the PSM Program for this site. For compliance with RMP regulations additional improvements are being considered. |