Moreno Valley RWRF - Executive Summary |
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RISK MANAGEMENT PLAN - MORENO VALLEY RWRF 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 Eastern Municipal Water District has an emergency response plan in effect to handle potential emergency situations at the Moreno Valley Regional Water Reclamation Facility (RWRF). This Emergency Response Plan was designed to meet the following objectives: 1.) To save lives. 2.) To minimize and avoid injuries. 3.) To protect the environment. 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 that 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 Moreno Valley RWRF maintains a maximum quantity of 110,400 pounds of chlorine on-site for use in disinfecting wastewater treated by the plant. There is a single chlorination building located at the facility housing two 30-ton bulk chlorine storage tanks (t anks can be filled up to 92% of capacity). These tanks are maintained by Eastern Municipal Water District employees or their designated contractor and are refilled by the bulk chlorine supplier under the supervision of District employees. Chlorine gas is supplied from the bulk tanks to five chlorinators (one 1,000-pound per day, three 2,000-pound per day and two 3,000-pound per day units) which regulate the chlorine feed rate via two pressure regulating valves that shut off upon loss of vacuum downstream. A vacuum is created at the chlorinators by water flow through a set of injectors. Hazard Assessment Summary Worst Case Release Result Summary Scenario Description: Release of the maximum quantity (92% of maximum capacity) of chlorine that can be stored in the largest vessel - 55,200 pounds in 10 minutes. The storage tank is located in a building; therefore, this passive mitigation measure was incorporated in the calculations. The most pessimistic meteorological conditions wer e used: 1.5 meters/second wind speed and F stability (a measure for turbulence. Although the chlorination building is equipped with an automatically actuated scrubber system, it was considered to be inoperable for the purposes of this worst case scenario. The reference chart included in EPA's RMP Guidance for Wastewater Treatment Plants was used to determine the maximum downwind distance to 3 ppm. With these assumptions in place, the toxic plume extends offsite. Alternative Release Result Summary Scenario Description: Two alternate scenarios were considered. The first consisted of a liquid release outside the chlorination building or inside the building with the doors open with a release rate of 150 pounds per minute from a < inch hole. This scenario simulates a hose rupture during filling operations that does not lead to actuation of truck-mounted shut off systems. The second scenario consists of the same release parameters as the first scenario, but inside the chlorination bui lding with the doors closed and the scrubber system activated per design. Only in the case of the first scenario does the toxic plume extend offsite at a concentration of 3 ppm. Accidental Release Prevention Program and Chemical-Specific Prevention Steps The Eastern Municipal Water District 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, including common practices outlined by the Chlorine Institute. In addition to the Management Programs, there are chlorine leak detectors situated in all rooms that contain chlorine. In the event of a chlorine gas leak reaching 1 ppm, the detectors relay a signal that activates a horn and a light outside the room where chlorine has been detected. In addition, the alarm is displayed on the SCADA monitors. At 3 ppm, the alarm signal actuates the emergency scrubber system for the chlorinati on building. Five Year Accident History The five-year accident history (June 1994 through June 1999) for the Moreno Valley RWRF reveals that there were no incidents that involved a release of chlorine. Planned Changes to Improve Safety Several 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. |