South Wastewater Treatment Plant - Executive Summary |
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General Executive Summary for Brownsville Public Utilities Board South Wastewater Treatment Plant 1. Accidental Release Prevention and Emergency Response Policies We at South Wastewater Treatment Plant are strongly committed to employee, public and environmental safety. This commitment is demonstrated by our comprehensive accidental release prevention program that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at our facility. It is our policy to implement appropriate controls to prevent possible releases of regulated substances. 2. The Stationary Source and the Regulated Substances Handled Our facility's primary activity is sewage wastewater treatment. We have 1 regulated substance present at our facility. This substance is chlorine. Chlorine is used as a disinfectant. 3. The Worst Case Release Scenario and the Alternative Release Scenario, including administrative controls and mitigatio n measures to limit the distances for each reported scenario To perform the required offsite consequence analysis for our facility, we have used the EPA's Offsite Consequence Analysis (OCA) Guidance Reference Tables and Equations. The following paragraphs provide details of the chosen scenarios. The worst case release scenario submitted for Program 2 (chlorine toxic substance) involves a catastrophic release from our chlorine injection process. In this scenario 2000 lb. of chlorine is released. The toxic liquid released is assumed to form a 1-cm deep pool from which evaporation takes place. The entire pool is estimated to evaporate over 10 minutes. A passive mitigation system such as an enclosure is taken into account to calculate the scenario. At Class F atmospheric stability and 1.5 m/s wind speed, the maximum distance of 3.5 miles is obtained corresponding to a toxic endpoint of 0.0087 mg/L. The alternative release scenario for chlorine involves a release from our chlorine i njection process. The scenario involves the release of 2000 lb. of chlorine. Toxic gas is assumed to be released from a pipe leak. The estimated time for the pipe to leak all of the cylinder's content is 60.28 minutes. A passive mitigation control such as an enclosure is taken into account to calculate the scenario. The release is also assumed to be controlled by a scrubber. Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.0087 mg/L of chlorine is 0.30 miles. 4. The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps Our facility has taken all the necessary steps to comply with the accidental release prevention requirements. This facility was designed and constructed in accordance with TNRCC 317 Design Criteria for Sewerage System. The following sections briefly describe the elements of the release prevention program that is in place at our stationary source. Process Safety Information South Wastewater Treatment Plant maintains a detailed record of safety information that describes the chemical hazards, operating parameters and equipment designs associated with all processes. Operating Procedures For the purposes of safely conducting activities within our covered processes, South Wastewater Treatment Plant maintains written operating procedures. These procedures address various modes of operation such as initial startup, normal operations, temporary operations, emergency shutdown, emergency operations, normal shutdown and startup after a turnaround. The information is regularly reviewed and is readily accessible to operators involved in the processes. Training South Wastewater Treatment Plant has a comprehensive training program in place to ensure that employees who are operating processes are competent in the operating procedures associated with these processes. Refresher training is provided at least every year and more frequently as needed. Maintenance South Wastewater Treat ment Plant carries out highly documented maintenance checks on process equipment to ensure proper operations. Process equipment examined by these checks includes among others; one ton chlorine cylinder, piping systems, relief and vent systems, scrubber system, and controls. Qualified personnel carry out maintenance operations with previous training in maintenance practices. Furthermore, these personnel are offered specialized training as needed. Any equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner. Compliance Audits South Wastewater Treatment Plant conducts audits on a regular basis to determine whether the provisions set out under the RMP rule are being implemented. The most recent compliance audit was conducted on 03/31/1999. These audits are carried out at least every 3 years and any corrective actions required as a result of the audits are undertaken in a safe and prompt manner. Incident Investigation South Wastewater Tre atment Plant promptly investigates any incident that has resulted in, or could reasonably result in a catastrophic release of a regulated substance. These investigations are undertaken to identify the situation leading to the incident as well as any corrective actions to prevent the release from reoccurring. All reports are retained for a minimum of 5 years. 5. Five-year Accident History South Wastewater Treatment Plant has had an excellent record of preventing accidental releases over the last 5 years. Due to our stringent release prevention policies, there has been no accidental release during this period. 6. Emergency Response Plan South Wastewater Treatment Plant follows a written emergency response plan to deal with accidental releases of hazardous materials. The plan includes all aspects of emergency response including adequate first aid and medical treatment, evacuations, notification of local emergency response agencies and the public. To ensure proper functioning, our emergency response equipment is regularly inspected and serviced. In addition, the plan is promptly updated to reflect any pertinent changes taking place within our processes that would require a modified emergency response. 7. Planned Changes to Improve Safety Several developments and findings have resulted from the implementation of the various elements of our accidental release prevention program. Additional training to employees is one of the major steps we want to take to improve safety at our facility. |