Interstate Technical Group on Abandoned Underground Mines
Fourth Biennial Abandoned Underground Mine Workshop
Abstract: Iowa Department of Transportation
The Iowa DOT is not currently working on any project that involves possible or probable subsidence problem to highways due to abandoned underground mines. The two most recent potential subsidence problems that the Iowa DOT has faced are possible threats from relative to shallow coal mines and from sinkholes.
The most recent mine investigation was approximately two years ago involving the Ottumwa Bypass (US 63). This involved the investigation of a potential threat to road construction and stability due to the presence of abandoned coal mines in the vicinity. The geotechnical consultant for this project was CH2M Hill. The consultant worked closely with the Soils Design Section of the Office of Design, IDOT to coordinate and evaluate both passive and invasive subsurface investigation. The result of this was to determine that there was no threat to either road construction or stability. Roch Player from CH2M Hill may elaborate on this in his presentation.
In the northeastern quarter of the state the Iowa DOT has been concerned with sinkholes along the portion of the Avenue of the Saints in Chickasaw County (US 218). The Soils Design Section has been and continues to work on/refine remediation procedures for sinkholes.