City of Woodland Water Pollution Control Facility - Executive Summary
FEDERALLY MANDATED RMP SUBMISSION |
1. Accidental Release Prevention and Emergency Response Policies
The City of Woodland uses chlorine and sulfur dioxide at its Water Pollution Control Facility (CW-WPCF). The chlorine and sulfur dioxide are stored in the Chemical Building is liquified chorine gas under pressure and is considered a hazardous material; Chlorine gas and sulfur dioxide gas are also Regulated Substances under the California Accidental Release Program (CalARP). The Yolo County Office of Emergency Services recognized the CW-WPCF as a Stationary Source under the CalARP regulations and requested this Risk Management Plan (RMP). The City of Woodlands policy is to adhere to all applicable Federal and State of California rules and regulations. Safety depends upon proper construction design and safety features of the facility, accurate operating and emergency procedures, and effective training of personnel.
2. Stationary Source and Regulated Substances
he Chemical Building at CW-WPCP is an enclosed structure located at 42929 County Road 24 in Woodland, California. As a Stationary Source, there are two Federally Regulated Substances and two Regulated Processes. The Regulated Process for chlorine and for sulfur dioxide include: gas container unloading and storage, a metering/mixing device, and an gas-in-solution injector. When chlorine gas is dissolved in water, it is no longer a Regulated Substance in the CalARP.
The chlorine gas and the sulfur dioxide gas are trucked to the facility in one-ton containers. There are 12 one-ton containers of chlorine and eight one-ton containers of sulfur dioxide stored in the Chemical Building. For each gas, two one-ton containers are connected to the feed system; the remaining containers are kept in reserve.
3a. Worst Case Release Scenario
The Worst Case release scenario for interconnected equipment must consider the largest quantity of a regulated substance handled on site in a single vessel
at any time, taking into account administrative controls on the vessels contents and usage as per the CCR Title 19 Division 2 Chapter 4.5 Article 2 Section 2750.3(b).
For chlorine and for sulfur dioxide, a 2,000-lb container is considered the largest vessel in these two feed systems. The one-ton container is, at most, filled with 2,000 lb of liquid chlorine. The Worst Case release scenario for the one-ton container is the release of the entire capacity at a rate of 200 lbs per minute for a ten-minute duration.
The distance to the 3 ppm (0.0087 mg/L) would extend beyond the boundaries of the stationary source.
3b. Alternative Release Scenario
The Alternative Release scenario for the one-ton container is complete failure and separation of a quarter-inch fuse plug in the end of the container. All 2,000 lbs of chlorine or sulfur dioxide are assumed to flash to vapor.
The distance to the end point of 3 ppm (0.0087 mg/L) for the chlorine release would extend beyond the boundaries o
f the stationary source.
The distance to the end point of 3 ppm (0.0078 mg/L) for the sulfur dioxide would extend beyond the boundaries of the stationary source.
3c. Administrative Controls
Administrative controls to limit the distances for each reported scenario exist to restrict, to a minimum, the amount of chlorine lost from a one-ton container if an accidental release were to occur; and preferably to not have a release occur. These administrative controls are inherent in the operational procedures for the regulated substances processes and the training provided to the operators. Administrative controls are also in place for the regulated processes.
3d. Mitigation Measures
Mitigation measures to limit the distances for each reported scenario exist to restrict the amount of the regulated substances released to a minimum, if a release were to occur; and preferably to not have a release occur. The mitigation measures are based on the design, inspection, testing, and maintenance
of the regulated processes and their related equipment and components.
4. General Accidental Release Prevention Program and Chemical Specific Prevention Steps
The facility complies with all applicable Federal and State codes and regulations. There are safety meetings and safety training. The Process Safety Management (PSM) program implemented at the facility for the regulated processes and their related activities and equipment represents the facilitys main active commitments to an accidental release prevention program.
5. Five Year Accident History
There have been no accidental releases of regulated substances within the last five years.
6. Emergency Response Program
The Emergency Response Program is based upon the alerting of personnel at the facility to evacuate or shelter-in-place and await the arrival of responders from the local area responder at the assembly location if a release occurs that causes the evacuation or the shelter-in-place to be initiated.
7. Planned Cha
nges To Improve Safety
Current applicable codes and regulations are reviewed as part of the Process Hazard Analysis element of the Process Safety Management (PSM) program to determine if commitments need to be made to achieve increased operational safety for the regulated processes. These commitments address prevention and mitigation measures for accidental releases of the regulated substances. The completion schedules for these commitments are included in the PSM.