LYNNWOOD WASTEWATER TREATMENT FACILITY - Executive Summary
1.Accidental release prevention and emergency response policies: |
The Lynnwood Wastewater Treatment Facility utilizes chlorine. Since we have more than 2,500 pounds of chlorine stored on site, we are required to have a Risk Management Plan.
Chlorine is an integral element in our disinfection system, being necessary for public sanitation and for protection of the waterway (Puget Sound) into which our treated effluent is discharged. At the same time, the properties of chlorine make it necessary to observe certain safety precautions in order to prevent any threat to our own personal health, co-worker, and nearby members of our service area. It is our policy to adhere to all applicable Federal and state rules and regulations. Safety depends upon the manner in which we handle chlorine, the secure devices in the design of the chlorine handling system, and the on-going safety training of our personel.
Our Emergency Response Plan (ERP) was prepared by Prezant Associates in conjunction wi
th the Lynnwood Fire Department, Don Davis (treatment plant supervisor), and revised by treatment plant personnel. Our Chlorine System Process Safety Management Plan (PSM) was developed by HDR Engineering.
2. Our facility and the regulated substances handled:
The Lynnwood Wastewater Treatment Facility is responsible for domestic and commercial wastewater collection,treatment and disposal within our service boundaries. The treatment facilities are intended to protect the public health and the beneficial uses of the waters in the area. The facility reduces the suspended solids and biochemical oxygen demand (BOD) of the influent sewage. The wastewater passes through several processes to remove these pollutants; chlorination is utilized to reduce the disease-causing constituents of the sewage. The treated water is discharged into Puget Sound while the resulting sludge is disposed of by incineration.
The maximum amount of chlorine that can be stored at this facility is 12000 pounds.
worst-case scenario and the alternative release scenario, including administrative controls and mitigation measures to limit the distances for each reported scenario.
* Worst-Case Scenario: The EPA has set the conditions for the worst-case scenario, namely, that the largest storage tank fails catastrophically and empties itself in 10 minutes on a day with a 10 mph wind. Using EPA's model, chlorine would be detectable over an area with a radius of 0.9 miles from the facility.
* Alternative Scenario: A more likely scenario would be the case of a pipeline, which goes from the chlorinator room to the diffusers, should rupture. In this case chlorine might be detectable approximately 150 feet from the chlorine room.
3a. All chlorine cylinders are located inside the chlorine storage room. No cylinders are stored outside. All handling of the one ton cylinders is done directly between the delivery truck and the trunnions upon which the cylinders lie.
3b. A chlorine leak alarm sounds at 2.0 ppm
. The room has continuous air monitoring.
3c. If the chlorine level does not decrease, the Lynnwood Fire Department's Haz-Mat Team is called to the plant. If necessary, in the worst-case scenario, they have the ability to spray a curtain of water, containing the gaseous chlorine. They will have properly equipped personnel entering the chlorine room to correct any problem. Also in conjunction with the Lynnwood and Edmonds Police Departments they have a plan to notify the surrounding affected neighborhood.
In the case of the alternative scenario the Lynnwood Fire Department Haz-Mat Team has a Chlorine Institute "B-Kit" to quickly repair leaks.
3d. The chlorine cylinders are strapped down to prevent movement in the event of an earthquake.
3e. The overhead I-beam and trolly system are tested on a regular basis.
3f. A large window has been inserted in the chlorine room delivery door so that visual inspection of the room can be done on a continuous basis.
4. The general accidental release pr
evention program and the specific prevention steps.
This program is covered under a separate regulation, Process Safety Management (PSM), which was developed by HDR Engineering for the City of Lynnwood. Hazard analysis, operating procedures, training, contractors, safety review, mechanical integrity, hot work permits, management of change, incident investigation, emergency planning and compliance audits are all covered in this program.
5. Five-year accident history:
We have had no accidental releases of chlorine in the past 5, 10 or 20 years.
6. The emergency response program.
The facility has had an Emergency Response Plan for several years with the most recent revision done on January, 2000.
The response plan for a chlorine leak depends upon the severity of the leak. Trained facility personnel are responsible for containing miniscule leaks. Response to a large leak or an unconfined leak becomes the responsibility of the Lynnwood Fire Department.
New employees are not allowed to work
on processes involving chlorine until they have had adequate training. All Operations and Maintenance personnel shall receive annual chlorine handling and emergency response plan refresher training. Classroom and/or hands-on training session duration is listed below.
TOPICS TIME (Hrs.)
1. chlorine emergency response procedures 2
2. chlorine cylinder handling and connect/disconnect procedures 1
3. first aid and CPR 4
4. hazard communication refresher 2
5. confined space procedures 1
6. chlorine equipment preventive maintenance procedures
7. chlorine equipment correcxtive maintenance procedures 2
Exercises will be conducted as follows: in-plant = once/quarter
external = once/year, coordinated with Lynnwood Fire Department
Public notification will be the responsibility of the Lynnwwod Fire Department. If necessary, in conjunction with the Police Department, the affected neighbors will be notified.
The facility has a continuous monitoring system in the chlorine tank room and has chlorine alarms in 3 other places that will sound a horn. The horn warns facility personnel to evacuate. The chlorine alarm sends a signal to Washington Alarm, an off-site security company, who calls in the Lynnwood Fire Department. 911 will also bring in the Fire Department.
7. Planned changes to improve safety:
HDR Engineering is in the process of completing an "Alternative Disinfec
tion Study" for the facility. It is our intention to replace gaseous chlorine at the facility with a safer disinfection system within the next four years.