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.
Incident Management Situation Report (IMSR)
Incident Response Pocket Guide (IRPG), PMS 461
NWCG Standards for Helicopter Operations, PMS 510
RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR)
Interagency Standards for Fire and Fire Aviation Operations (Red Book)
Wildland Fire Lessons Learned Center