Joint Water Commission - Executive Summary
This Risk Management Plan (RMP) is submitted to the United States Environmental Protection Agency (US EPA) in a timely manner for the Hillsboro, Forest Grove, Beaverton, Tualatin Valley Water District Joint Water Commission Treatment Plant, which handles one of the listed substances in Appendix A Part 68. |
1. Regulated Substance Handled
The Hillsboro, Forest Grove, Beaverton, Tualatin Valley Water District Joint Water Commission Treatment Plant, more commonly known as the Water Treatment Plant, is managed and operated by the City of Hillsboro personnel. The regulated substance handled is chlorine which is considered hazardous by the US EPA.
Gaseous chlorine is stored in 1 ton cylinders located in the facility chlorine storage room. The maximum quantity of chlorine that can be stored at the facility is 12,0000 lbs. (6 tons).
2. Accidental Release & Emergency Prevention Program
The Water Treatment Plant takes a systematic proactive approach to preventing accidental releases of chl
orine. The plant is strictly covered by OSHA Process Safety Management (PSM) standard 29 CFR 1910.119. The prevention of accidental releases depends on adherence to the procedures used to handle chlorine, the safety equipment systems designed and constructed in the facility, and the training of pertinent personnel. The RMP/PSM manual and other various safety programs are kept in the main controls room for employee purview.
Engineering controls have been added as part of the prevention program to limit the distances for each of the submitted scenarios. The Water Treatment Plant has installed a chlorine scrubber which is designed to capture and treat the contents of an entire one-ton cylinder. The system is also under a vacuum regulator that would cut off flow if a leak in the chlorine piping should occur.
3. Worst Case Scenario & Alternate Release Scenarios
The Water Treatment Plant used a more credible modeling computer program for its chlorine release scenarios. The America
n Water Works Association (AWWA) Research Foundation provided a guidance manual with scenarios for both worst case and alternate using the ALOHA modeling for chlorine.
Chlorine Worst Case:
The failure due to a corrosion, impact or construction defect for a filled one-ton cylinder would release 2000 pounds of chlorine over a 10-minute duration at 200 pounds per minute. The Water Treatment Plant is located in a rural environment therefore the distance to end point would be approximately 3 miles.
Chlorine Alternate Scenario:
Assuming a tubing failure, bad connection, or valve failure a release of a one-ton cylinder at a 60 minute duration would release 317 pounds over a distance to endpoint of 0.56 miles. This scenario is the most credible with the greatest distance to endpoint.
4. Emergency Response Program
Although an accidental chlorine release is unlikely, Water Treatment Plant prepares for releases and other emergencies. The plant has developed an emergency response written
plan specifically for chlorine releases which adheres to 29 CFR 1910.120. The written plan identifies responders roles and includes specific tasks for key personnel in the event of different scenarios, information on when to contact fire department, and required training for employees. The written program also addresses sheltering-in-place or evacuation methods.
The Water Treatment Plant is currently in the process of soliciting volunteers, from among our employees, to serve as emergency responders. Once this team is established there will be a schedule of training for first responders operational training, SCBA, and yearly refresher training where responders can demonstrate proficiency through simulated releases and emergencies which will be coordinated with the local Fire Department and possibly the state HAZMAT team. Training exercises will be evaluated and when the plan shows deficiency it will be updated.
5. Planned Changes to Improve Safety
Water Treatment Plant has identi
fied no major unresolved process hazards in the chlorine system.