StacksVerified U.S. regulatory reference

43 CFR §3832.41

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
A tunnel site is a subsurface right-of-way under Federal land open to mineral entry. It is used for access to lode mining claims or to explore for blind or undiscovered veins, lodes, or ledges not currently claimed or known to exist on the surface.