Jasper Municipal Water Filtration Plant - Executive Summary |
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Jasper Municipal Water Filtration Plant This facility has a practical overall approach to chemical safety (e.g. chlorine or any chemical used at the plant) in the water treatment process in the City of Jasper, Indiana as it relates to protection of the employees and surrounding population. Although, no strict municipal policy is in place other than what is required, this facility incorporates employee safety concerns in their safety decision-making process as evidenced by past safety inspections conducted at the plant. The Jasper Municipal Water Filtration Plant (as the name implies) is the local municipal water treatment facility for the City of Jasper. The plant uses chlorine for the disinfection of the treated potable water before it is pumped into the distribution system. Normally, two one-ton chlorine cylinders are stored at the plant. The worst-case scenario for this facility assumes that chlorine is completely released from 1 one-ton (2,000 lbs) cylinder over a period of 1 0 minutes. Using Exhibit 4-3 in the EPA's Risk Managment Program Guidance for Wastewater (also used for Water) Treatment Plants (40 CFR Part 68), the toxic endpoint for this urban site is 1.3 miles with a F stabiliity class and wind speed of 1.5 meters per second. There would be an offsite impact with this worst-case scenario. Although, the chlorine cylinders are kept inside an enclosed room (passive mitigation process), the cylinders are initially delivered and handled outside prior to being placed on the scale. One procedure which makes this worst-case scenario unlikely is that during the replacement of empty and full cylinders, the procedure is only conducted by a highly-experienced employee with two observers present. The alternate release scenario for this facility is the most likely event to occur that would result in a release of chlorine to a toxic endpoint. At this facility, the most likely event would be a blown pressure-relief valve or cylinder valve on the tank. However, this event would be mitigated by the fact that it most likely would occur inside an enclosed room where chlorine sensors are present. Using Exhibit 4-13 from the above guidance, the release rate and distance to an endpoint for a liquid chlorine release through a 1/4-inch diameter valve opening (closest and most conservative size to actual 3/8-inch diameter value opening) are 150 lbs/min and for a urban setting 0.2 miles, respectively. This facility is subject to EPCRA 302 with regards to chlorine. In addition, this facility ensures compliance with safety information requirements under NFPA 820 (For wastewater/water treatment plants), OSHA (29 CFR 1910.111) and local building codes. The following practices are conducted as part of this facility's prevention program: (1) Annual classroom training on how to handle chlorine and associated releases, (2) monthly toolbox safety meetings (on how to use SCBA, etc.) and (3) on-the-job training with experienced personnel. No acc idents have been recorded at this facility wthin the last five years due to the stability and training of the workforce at the plant. The plant's emergency response plan includes general procedures, emergency alarms, evacuation sites, procedures for emergency shutdown of operations, identified hazards and who responds and how, control of workplace hazards, maintenance of emergency equipment with emergency telephone listing (public entities, etc.). There is close coordination of emergency response measures with Local emergency response committee. The following changes to improve safety are planned for this facility: 1) More complete documentation of what employees receive training and the type of training received. 2) More frequent toolbox safety meetings (e.g, biweekly). 3) Updated process hazard analysis as per 1910.119 4) Updated and complete emergency response (action) plan for site to incorporate more details with regards to responding to accidential releases of chl orine and/or other regulated substances. 5) Performance of a yearly compliance audit to ensure that the above changes are incorporated into this facility's safety program as well as continued adherence to the level of safety currently maintained by the water treatment plant. |