Fugitive emissions from sources which were constructed on or before April 25, 1971, shall not exceed 40% opacity. Fugitive emissions from sources constructed or modified after April 25, 1971, shall not exceed 20% opacity.

KEY: air pollution, fugitive emissions, mining, tailings

Date of Last Change: December 3, 2025

Notice of Continuation: October 2, 2024

Authorizing, and Implemented or Interpreted Law: 19-2-101; 19-2-104; 19-2-109