An  emergency is a sudden danger or impairment that presents a high probability of substantial physical harm to the health, safety, or general welfare of people before the danger can be abated under normal program operation procedures. Most emergencies in Iowa are caused by subsidence and mine shaft openings. 

Portals and Vertical  
(Mine Shaft) Openings 

Underground coal mines contained horizontal, sloped, or vertical shafts. Before the 1940’s shaft closure was not required when mining ceased. Shaft closures  (entrances and air shafts) can deteriorated with time and pose a threat to health, safety, and welfare of the public.  A direct opening to an underground mine should always be reported promptly and should never be explored.

mine shaft opening

Targeted Hazards 

Subsidence occurs when an underground mine can no longer support material above it  and collapses. Structures, under-ground utilities, and other features may be damaged as a well. Subsidence is most often characterized by a sudden sinking event. Site investigation is needed to determine if the subsidence is caused by an underground coal mine.  

Additional Hazards 

Other problems exist as well such as flooding, acid drainage, gas release, and mine spoil piles. If you suspect a mine-related emergency, report it immediately to the Iowa Mines and Minerals Bureau.