Theresa Mine headframe and ore bin, Cripple Creek, Colorado, August 2011. Photo credit: Vince Matthews for the CGS.

Historic Mining Districts

Colorado’s historic metal mining districts tell the tale of a state rich in mineral resources. From precious metals to lead, zinc, copper, molybdenum and tungsten: the state has a variety of mineral deposits that are still mined today. Geologists and miners recognized a broad area throughout the central part of the state that contained many precious minerals, the so-called Colorado Mineral Belt. This region has produced much of the state’s mineral wealth for many decades, beginning in the late-1800s. Prospectors came from all parts of the world to seek their fortune in the Rocky Mountains. When prices of metals were high, mining (and miners) had boom times, creating large communities like historic Leadville. Some towns completely disappeared after mineral prices fell or when mineral resources were depleted.

A Pikes Peak prospector in front of his log home, circa 1900. Photo credit: William Henry Jackson, Library of Congress.
A Pikes Peak prospector in front of his log home, circa 1900. Photo credit: William Henry Jackson, Library of Congress.

Many mining-related structures stand as a testament to Colorado’s metal mining history and are listed in the State or National Register of Historic Properties. Some of these structures may be seen in towns such as Idaho Springs and Silverplume along Interstate-70. Mine waste piles and openings—adits and shafts—from these operations may be spotted throughout the entire state. Many of the historic mining features we see today are the result of mining prior to the enactment and implementation of federal and state laws that govern mining and protect human health and the environment. The CGS has assisted the U.S. Forest Service with studying some of these issues, see: ON-008-04D U.S. Forest Service Abandoned Mine Land Inventory Project – Colorado (Data). It has also aided several federal and state agencies with cataloging information about abandoned mines in the state. Some of these abandoned mine areas directly impact surface water and/or groundwater. Both the Colorado Department of Public Health and Environment and the US Environmental Protection Agency work with other public, local, state, and federal stakeholders to study and clean-up these sites.

Most of the federal environmental laws that regulate active mines, other industries, and environmental remediation of abandoned sites were implemented in the 1970s and 1980s. Colorado state mining laws were developed in the 1960s and 70s and include the Open Mining Land Reclamation Act of 1973 which established a permit process and limited bonding for coal mines and other industrial mineral producers. In 1976, the Colorado Mined Land Reclamation Division was created under the Department of Natural Resource (DNR) to regulate non‐coal mining operations.

Today, the DNR’s Mined Land Reclamation Board and Division of Reclamation, Mining and Safety (DRMS) promulgates the State rules and regulations associated with mining, mine safety, and the reclamation of abandoned mines. While these areas are interesting and celebrate the miners and geologists of the past, these historic structures, waste piles, and mine openings are dangerous and should be enjoyed from a safe distance.