Tunnel City

About the Program
The Covia Tunnel City site is in Tomah, central Wisconsin. Covia acquired the site in 2011, and it is used as a metallic mineral mine that utilizes open pit quarrying to produce industrial sand. Historically, a portion of the site was owned by Union Pacific Railroad, and the rest was a combination of residential homes, forest and farmland. 

Practices and Impacts

• This site contains 117 acres of pollinator-friendly habitat. During 2023, 20 additional acres were reclaimed from previous mining activity and were planted with native plants that serve as habitat for native pollinators, such as the Karner blue butterfly, and native bird species, including the eastern bluebird and American kestrel. 
• The site contains bat boxes and tunnels that provide habitat for bat species. The team installed a bat-friendly gate that allows bats to access the tunnel while preventing human disturbance. The tunnel contains the deadly white-nose syndrome, and this project plays an important role in the study of the disease. Researchers survey the bat populations within the tunnel to understand the disease's impact, and some bats are taken from the tunnel in order to be used to study treatment for the disease. 
• The team manages 117 acres of habitat for the Karner blue butterfly, an endangered butterfly species. They plant native vegetation for the benefit of the butterfly species, particularly the wild lupine, which plays a crucial role in the butterfly's life cycle. Wild lupines and Karner blues are found throughout the site.