City of Findlay Water Treatment Plant - Executive Summary |
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The City of Findlay's Water Treatment Plant (WTP) utilizes more than a threshold quantity of chlorine (2,500 pounds) in their process. Therefore, this facility is required to submit a Risk Management Plan (RMP) as defined in '68.150 by June 21, 1999. Public employees are covered under the State of Ohio's Public Employee Risk Reduction Program (PERRP), which has adopted by reference the requirements of OSHA's (PSM) standard. Based on the March 1999 revised USEPA RMP Guidance for WWTPs, the Findlay Water Treatment Plant is subject to the OSHA Process Safety Management (PSM) standard because of the Ohio law and is therefore subject to the Program 3 requirements of the RMP Regulations. '68.155(a) Accidental Release and Emergency Response Policies The Findlay WTP has documented emergency response procedures in place, as documented in the facility's Emergency Action Plan. This plan has been endorsed by the City staff responsible for the operation and maintenance of the Findlay WTP. Th e City of Findlay WTP has procedures in place, including both onsite activities and coordination with offsite responders, that must be followed in the event of a chlorine leak. All personnel involved in handling chlorine are trained with regard to chlorine safety and accident prevention. '68.155(b) Stationary Source and Substance Handled The stationary source subject to 40 CFR Part 68 is the City of Findlay WTP Chlorination Facility. The Findlay WTP has a capacity of 16 MGD and treats surface water to drinking water standards. The Findlay WTP chlorination facility is located in a single room in the WTP Chemical Building. It consists of the combined storage of chlorine ton containers and chlorination feed equipment for chlorine solution feed. Provisions are made to house ten (10) one-ton containers. Four chlorine containers are placed on scales and are connected to the manifold; two of them are in service and the other two are on stand-by for automatic changeover when the conte nts of the on-line containers are exhausted. The remaining six tanks in the chlorination room are stored on truions. As the manifolded containers are exhausted, containers are moved from storage to the scales and the empty containers are placed on truions until the next shipment of chlorine is received. Chlorine gas is fed from the containers through the vacuum regulator on the manifold adjacent to the scale for vacuum feed. Vacuum chlorinators and associated chlorine injectors are provided for solution chlorine feed at various process locations. Vacuum chlorine feed reduces the likelihood of a release into the environment. A chlorine leak detector is installed in the Chlorine room to alert the plant staff quickly in the event of a chlorine leak. The chlorine leak detector is located next to the chlorinators. Audible alarms automatically sound inside and outside of the building when chlorine levels reach 1 ppm. '68.155(c) Offsite Consequence Analysis As a Program 3 Process w ith one toxic gas, one worst-case release scenario and one alternative release scenario will be assessed for the Chlorination Facility. The City of Findlay WTP has chosen to use the US EPA Risk Management Program Guidance for Wastewater Treatment Plants (40 CFR Part 68), US EPA 550-B-98-010, October 1998, (WWTP Guidance), as a source to determine off-site consequences. This guidance specifically addresses the chemicals commonly found at WWTPs. The chlorination process for WTPs is similar to the chlorination process at WWTPs. Therefore, this guidance document is applicable to the Findlay Water Treatment Plant's chlorination process. The worst-case release scenario was determined in accordance with the requirements provided in 40 CFR 68.22 and 40 CFR 68.25(b,c). For the Findlay WTP facility the worst-case scenario is a total release from one of the one-ton containers of chlorine (greatest amount held in a single vessel) over 10 minutes. This results in offsite impacts. The facilit y is also required to complete at least one alternative release scenario that reaches an endpoint offsite. The alternative release scenario was evaluated in accordance with the guidelines provided in 40 CFR 68.22 and 40 CFR 68.28. The most likely release scenario is identified based on the results of the Process Hazard Analysis (PHA). The alternative release scenario for chlorine that results in offsite impacts is a vapor release through a 3/16 inch opening in a leaking valve, gasket, flexible tubing line, or pipe. The passive mitigation of the building was incorporated in this scenario. '68.155(d) Accidental Release Prevention Program The Findlay WTP facility has a documented Prevention Program for the chlorination facility that documents release prevention measures. These prevention measures include elements such as employee participation, process safety information, process hazard analysis, operating procedures, training, contractors, pre-startup review, mechanical integrit y, hot work permits, management of change, incident investigation, and compliance audits. Findlay WTP is equipped with leak detection monitoring to decrease response time in the event of a chlorine leak. A chlorine leak detector is located next to the chlorinators and an output is provided to the plant monitoring and control system for chlorine leak monitoring and alarming process. Chlorine leak alarms are displayed and logged at the plant main control room and audible alarms automatically sound inside and outside the building if a chlorine leak is detected. Also, Findlay WTP employees who are involved in chlorine operations are trained in specific procedures regarding handling and storage of chlorine at the facility. '68.155(e) Five-Year Accident History The Findlay WTP facility has had no accidental releases of chlorine in the last five years that have resulted in on-site injuries or off-site injuries or other impacts. '68.155(f) Emergency Response Program The City of Find lay WTP is a non-responding facility, as defined by OSHA and EPA (29 CFR 1910.120 and 40 CFR part 311). Therefore the City of Findlay WTP has developed an Emergency Action Plan to ensure employee safety instead of an Emergency Response Program, as allowed by 40 CFR 68.90(b). The Findlay WTP facility Emergency Action Plan outlines actions required to respond to a chlorine emergency and has coordinated this plan with the City Fire Department. City Fire Department personnel are the designated first responders in the event of a chlorine emergency. Findlay WTP employees are not designated responders to a chlorine release. As specified in 40 CFR 68.90, Findlay WTP's Emergency Action Plan meets the exception listed in 40 CFR 68.90(b) and therefore, the facility is not required to have the Emergency Response Program of 40 CFR 68.95. '68.155(g) Safety Improvements Recommendations for safety improvements were identified in the Process Hazard Analysis (PHA) which was completed per OSHA 29 C FR 1910.119(e) in October of 1998 by Malcolm Pirnie, Inc. Recommended improvements were identified in three main categories: Standard Operating Procedures, Maintenance, and Training. According to the PSM, any safety improvements will be investigated concerning their impacts on other systems and/or procedures prior to implementation. Additional recommendations may be made upon review of any accidents and/or when the PHA is updated every five years. |