Fire departments are often the first responders to incidents that include spills of hazardous substances, such as vehicle accidents, fuel spills at gas stations, and other emergencies. For large spills of petroleum or hazardous substances, fire departments should call the Minnesota Duty Officer (800-422-0798, 651-649-5451), who will notify MPCA Emergency Response.

Small petroleum spills

Petroleum is a mixture of several toxic chemicals, many of which evaporate quickly. Smaller spills of petroleum products, such as gas, diesel fuel, waste oil, or other engine fluids can still create significant fire, traffic, and pollution threats by: 

  • Making roads slippery
  • Flowing into nearby bodies of water directly or through storm sewers, and harming wildlife and water quality
  • Soaking into soils and reaching groundwater that may be used for drinking water
  • Creating fire hazards near traffic or in buildings or sewers
  • Running into sewers and disrupting wastewater treatment or creating explosion threats

The chemicals in petroleum that do not evaporate quickly are biodegradable, which means they can be degraded or consumed by bacteria and other microbes in the soil. Optimum degradation occurs if the petroleum is diluted and there is enough air, water, and nutrients for the microbes. Firefighters can take advantage of these properties in cleaning up and disposing of waste from small spills.

Responding to small petroleum spills

  • STOP the source of the spill, if it can be done safely. Turn off nozzles or valves in the leaking container.
  • CONTAIN the spilled material. Catch the liquid in any vessel available. Spread sorbent materials such as kitty littler, sand, straw, wood chips, pads, or dirt to create a containment structure to prevent the material from flowing. Note that sorbents do not make petroleum nonflammable. Use solidifiers to immobilize the material and lower the vapor levels. Solidifiers are powders or liquid that react with petroleum to turn it into a rubbery substance.
  • REMOVE petroleum from water in nearby ponds and ditches with natural-material sorbents that will float, such as dry straw or grass. Rake up the contaminated sorbent and thin-spread so it will biodegrade. Or use synthetic sorbent "oil-only" pads or booms, which absorb oil and repel water, float on top of the water, and are easy to retrieve. With the MPCA’s approval, small amounts of contaminated sorbents can be burned in training fires.
  • COLLECT the contaminated sorbent and put in garbage cans or buckets. Remember to control ignition sources. Reduce residual slipperiness on roadways with a fresh layer of sand or other spreadable sorbent.
  • SECURE THE WASTE If the spill is at a business or the accident is involving a commercial vehicle, the business is responsible for disposing of the contaminated sorbent. Companies must call the Minnesota Duty Officer to report petroleum spills of greater than five gallons. The MPCA will direct businesses on proper disposal.

With the exception of used oil, waste from petroleum spills that have been reported and cleaned up immediately are exempt from Minnesota’s hazardous waste rules. A fire department can leave the contaminated sorbent with the business or leave it at the scene.

For very small spills, sweeping used sorbent onto a road’s shoulder is better than leaving it on the roadway or not using sorbent at all. A fire department can elect to collect and store the sorbent for later treatment or disposal. Contact MPCA Emergency Response for more information at 651-296‑6300.

Washing down spills

The MPCA does not recommend washing down spills on roadways. Flushing diesel or fuel oil usually leaves the pavement even more slippery, and sand must be spread afterwards. Washing down a gasoline spill may move the vapor/explosion hazard to a storm or sanitary sewer. Petroleum flushed to ditches or storm sewers may travel to streams or lakes, creating fish kills or harm to wildlife.

Detergents and dispersants

Using chemical detergents or dispersants to "dissolve" petroleum in water and wash it away can create unintended problems. Petroleum broken up by these chemicals will reform after a time and can generate flammable vapors after having run into sewers or ditches; sometimes dispersants actually increase the vapor level. The dissolved petroleum is also much more toxic to animal life and can travel more easily into the ground.

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