OF-87-03 Tri-Towns Subsidence Investigation, Weld County, Colorado


This CGS publication explores a community-wide approach to geologic hazard evaluation, mitigation, and land use in areas subject to the phenomena of subsidence caused by underground coal mining around the towns of Firestone, Frederick, and Dacono in Weld County. 52 pages. 14 figures. 3 tables. 3 plates (1:4,800). Digital PDF download. OF-87-03D

Excerpt from the Introduction:

Coal mining began in the western parts of the Boulder-Weld coal field in the early 1860s and had spread throughout the field by the 1880s. By the turn of the century several large mines were operating in the Tri-Towns Area and underground coal mining persisted in the area until [the 1980’s] when the Lincoln Mine closed as the result of a fire.

The towns of Firestone, Frederick, and Dacono owe their existence primarily to the mining activity and the need for housing and community support for the mine workers. These towns now form the nuclei of growing communities responding to the demand for suburban housing and infrastructure associated with the growth experienced throughout the Front Range urban corridor.

In the spring of 1983 representatives of the towns of Firestone, Frederick and Dacono, as well as the Tri-Area Planning Council requested that the Colorado Mined Land Reclamation Division conduct a study of potential mine subsidence and its impacts in the Tri-Towns Area. It was subsequently determined that the purpose and scope of such a study was within the purview of the State Inactive Mine Program and funding was provided to the Colorado Geological Survey to carry out this investigation. This report and accompanying maps and illustrations present the findings and conclusions of that investigation.