President Street Water Quality Control Plant - Executive Summary |
The President Street Water Quality Control Plant (WQCP) has served the City of Savannah and portions of Chatham County since 1973. To ensure proper treatment of the wastewater prior to discharging to the savannah river, chlorine is used to disinfect the plant effluent flow to ensure that all pathogen are destroyed. The disinfection feed rates varies from 100 lbs. per day to 700 lbs. per day, depending on the effluent quality and demand. The chlorine control system was recently upgraded with the installation of four cylinder mounted vacuum regulators, these units will shut off the flow of chlorine gas if there is a break in the chlorine supply line obviating the offsite impact. Disinfection of the plant effluent can be achieved by using chlorine gas or liquid, currently gas is utilized. The chlorine is trucked in 2000 lbs. containers. There are several chlorine leak detector in the chlorine system located in the process area and storage site perimeters, when a chlorine leak is detecte d, the leak dectors activates visual and audible alarms to alert the operations personnel. During February, 1999 the President Street WQCP completed its program 2 Risk Management Plant (RMP) in accordance with section 112 of the Clean Air Act. The RMP includes the following components: 1) Introduction, 2) Employee Involvement, 3) Process Hazard Analysis, 5) Operating procedures and Pratices, 6) Employee Training, 7) Contractor Information, 8) Pre-Startup Safety, 9) Mechanic Integrity, 10) Non-routine Work Authorization, 11) Management Change, 12) Incident Investigation, 13) Emergency Preparedness, 14)Compliance Audits. The information provided within these components are not to be considered all inclusive for every imaginable scenario. However, it is the intent of this plan to provide a organized approach to the safe operation of the chlorination system. Responsibilities: The Treatment Administrator has overall responsibility for ensuring that the Process Management Plan is followed, reviewed and updated. The Operation Superintendent will be responsible for Employee Involvement, Employee Training, Emergency Preparedness, Compliance Audits, Process Hazard Analysis, Management Changes, Process Safety Information, Operating Procedures and Practices. The Maintenance Superintendent will be responsible for Contractors, Pre-startup Safety, Mechanical Integrity, Monthly Maintenance Scheduling and Non- routine Work Authorization. Worst Case Scenario The worst case scenario in terms of a catastrophic release of chlorine gas, has been determine to be a structual failure of a 2000 lbs. chlorine cylinder. The probability of this worst case scenario happening is nil. For the wosrt case scenario it is a requirement of 40 CFR 68.25 for the largest full container on site to completely empty its contents within a 10 minute period. Distance to toxic endpoint of the worst case release scenario has been determined to be 1.3 miles from the from the President Street WQCP. Alternate Case Release Scenario The alternate case scenario has been determine to a leak at the cylinder valve due to a improperly installed lead washer. In accordance with the OCA guidance the leak duration of 60 minutes has been used. Distance to toxic endpoint of the alternate release scenario has been determined to .7 miles from the President Street WOCP. To reduce the risk and magnitude of potential releasees, written procedures for the safe handling and operation of the chlorination system has been implemented. In addition, work performed on equipment subject to cause a release requires a minimum of two personnel, personnel are also required to wear Self Contained Breathing Apparatus (SCBA) throughout the course of work associated with chlorination equipment. Any major work to be performed on the chlorination system is limited to day time only, to reduce the possibility of a chlorine release and to ensure suffcient personnel are immediately available should a release occ ur. To date, there has been no chlorine release from the President Street WQCP. The Savannah Fire Department Haz-mat division has surveyed the chlorine system and storgae area. The Haz-Mat division is located about five minutes from the President Street WQCP. The RMP has been recently update to reflect the installation of the chlorine cylinder vacuum regulators, reviewing and updating of the RMP will be on going. |