Ash Pit Hazards

Ash pits are an inherent and hidden risk to wildland firefighters that can cause severe burns and injuries. Ash pits are created when a ground fire consumes underground fuels creating an empty space that is imperceptible from the surface.

Environmental factors that increase the risk of ash pit formation after a wildfire:

• Extensive root systems of trees and shrubs.
• Deep duff or peat, which is the organic layer covering mineral soil.
• Landscapes that have once been cultivated or manipulated by heavy equipment, old dozer piles, sawmills, timber sale yards, or decking areas.
• Animal dwellings that have become filled with decadent combustible debris.
  • Small rodent holes,
  • Beaver holes near dams and stream beds, or
  • Badger and coyote dens.
• White ash is sometimes an indicator of ash pits, as are swarms of hovering insects.
• With the sun behind the suspected ash pit, look for small nearly translucent smokes that dissipate quickly above the ground.
• Ash pits often give off the smell of incomplete combustion or of creosote burning.

Mitigation measures to consider:

• Identification of high-risk landscape.
• Identify and flag all hazardous discovered ash pits.