Controlling Pesticide Incidents Part 2
DEPARTMENTS
Volunteers Corner
In the first article on pesticide fires (see Volunteers Corner, FIRE ENGINEERING, February 1986), I discussed how to identify the product and the safety precautions to take at the scene. This segment will cover:
- Confining the products,
- Controlling the fire,
- Post-incident operations.
Confining the products
Confining these dangerous commodities can present several unusual situations. In addition to safeguarding people and property, you will also have to protect the soil, any nearby surface water, the water table, and the air, if possible. In order to control the incident, you may have to use involved procedures, such as building lined pits to collect runoff or covering dusts or powders with plastic sheeting to eliminate blowing in the wind. In some cases, simpler procedures, such as building dikes across a doorway or around a storm sewer opening, may be sufficient.
Pesticides that require control may be in the form of solids, liquids, vapors, or gases. Vapors can be covered with foam, or depending on the specific gravity and solubility, water. It will be necessary to use an alcohol type foam to control many pesticides because the diluent or carrier is a polar solvent. Simple spills from a small container can be absorbed. You could place the container in a plastic bag, recovery drum, or other enclosure.
The most common confinement will be the construction of dikes from soil or any other readily available materials. This may require heavy equipment if there is a large amount of poisonous material or considerable runoff.
Once the dike is completed, foam should be placed on the surface to control ignition and vaporization. If the soil is loose and absorbing the liquids, a vacuum truck should be used to remove the products or they will have to be pumped into an impervious container. In a few cases, it may be possible to lessen air pollution by dissipating escaping gases; however, all runoff may have to be contained. You should request technical assistance before initiating such an operation.
Leaks from small pesticide containers can be handled in a manner similar to other toxic hazardous materials. In most cases, you should place the poisonous substances in an overdrum. This will be faster and safer than plugging or patching. Salvage drums must be properly labeled with their contents. Pre-incident plans should state where the resources for containment can be acquired immediately.
Controlling the fire
When the pesticides are spilled or burning, some basic tactics must be employed. You will need a control line that is 2,500 feet from the site in order to isolate the area and deny entry to everyone, except working emergency response personnel. You should establish an exclusion area, especially downwind, and start evacuation procedures when possible danger exists.
Perform rescue of people or animals, decontaminate victims before transporting, and send as much technical information as possible to the hospital, including the label from the pesticide container. Always seek technical assistance during pesticide incidents, either locally or from other agencies.
Pesticide fires can be caused by: burning sulfur powder, exploding aerosol cans, rupturing drums, bulk pesticides, or a mixture of several of these. You must make an early strategy decision based on the size of the fire, control problems, and exposures.
If the fire can be controlled quickly with the creation of little runoff, it should be extinguished. On the other hand, if there is a situation that will create considerable runoff and related problems, it is often better to let the fire burn. This decision will depend on the number of people exposed downwind and on the amount of fallout from the smoke.
You can assume that the fire will consume about 50% of the pesticides. Wettable powders and water-based pesticides will not burn. Flammable pesticides will be made less harmful when exposed to a flame temperature of 1,800° F for two seconds. It is the general procedure to use as little water as possible in the extinguishment.
High-expansion foam has been recommended as a possible extinguishing agent because its low water content can reduce runoff. However, in outside fires it has a tendency to blow away if there is any wind; and if oxidizers are present, the fire can continue to burn under the blanket and destroy it.
In some cases, it will be necessary to use an inert material like sand to complete extinguishment without runoff. This can require special equipment.
During firefighting operations at a pesticide incident, remember to protect everyone exposed, including departmental personnel, and extinguish the fire creating as little runoff as possible. If the fire cannot be extinguished with a small controlled runoff, LET IT BURN.
Post-Incident operations
Even after the incident has been stabilized, do not disregard the safety considerations. All personnel and equipment must be properly and adequately decontaminated. Equipment that cannot be cleaned will have to be discarded. Be watchful for products that permeate rubber.
Cleanup operations of the site and property are not the responsibility of the fire department. Cleanup should be completed by a professional provided by the manufacturer or owner. The fire department must insist that all safety precautions are taken and that proper procedures are followed.
Continued on page 12
Continued from page 8
Rubble will have to be hauled to an approved disposal site, and concrete pads and remaining structural components will have to be decontaminated. In addition, the soil should be removed to a level below the contamination and disposed of suitably. Adequate security must be maintained during the cleanup.
Decontaminating personnel will be the major problem for the fire service. You must seek technical advice when choosing a decontaminating agent. Runoff must be contained and disposed of properly. Decontamination should be done as close as possible to the incident site to avoid spreading the materials. Because cold or inclement weather can make this even more difficult, prior planning is necessary.
Summary
As you can see, pesticide incidents can cause extensive problems. In order to minimize the effects, you must identify the potential in your company’s area and initiate pre-incident planning for the possible pesticide incidents in your community. This planning must include all aspects of safety, containment, and fire and spill control operations with the needed resources and agents, and cleanup operations.
