Efforts by federal, state, and local entities to assess and address pollution in Colorado are ongoing.  The results of the study are presented on the Abandoned Mines Water Quality Webportal. Red locations were visited and have water quality data, photos and completed field survey forms, unless these mines were not discharging water at the time of visitation. Yellow and Green locations provide mine name and locational information.

The 148 mines survey represent a subset of the roughly 230 mines the Division of Reclamation Mining and Safety identified as potentially impacting water quality. These mines were classified into three categories:

  • Green – Draining mines with partial to complete restoration (44)
  • Yellow – Draining mines with recent investigation or restoration project in process (32)
  • Red – Draining mines without recent investigations or restoration project


The Colorado Abandoned Mine Lands Database was created through collaboration with multiple state and federal agencies. Additional abandoned mine reclamation information was provided by the Colorado Division of Reclamation Mining and Safety. Agencies responsible for the data can be contacted with questions.  These agencies include: