Acid Mine Drainage

What is AMD?

Acid mine drainage (AMD), also referred to as abandoned mine drainage or abandoned mining lands (AML), refers to the red-orange "rust" often seen in our waterways and the land that they cover. Clearfield County has a rich history of clay and coal mining, with nearly 600 mining sites throughout and over 3,300 mining features such as shafts, entries, and spoil piles. When mined areas are exposed to air and natural elements, chemical reactions occur that create acids and metals that are not usually found in these areas. Groundwater then carries away the pollutants, leaving trails through our waterways and poisoning the native life our streams support. A more in-depth look at AMD can be found at the Clearfield County Waters website.

So how can we combat AMD? Luckily, we have the ability to clean up abandoned mining sites and have been doing so for over 20 years. Passive treatment systems, which do not require additional daily work or energy to function, have been built throughout the county at particularly strong AML sites. There are many types of passive treatment systems that are custom chosen to meet the needs of each unique site, using natural reactions and filtering to remove metals from the water and raise pH levels. Acidic water can flow through limestone, a naturally alkaline material, to become neutralized before continuing downstream. These large-scale restoration efforts have already made huge improvements to the water quality within our county, allowing trout to return to their native homes and folks to safely enjoy our natural resources.

See some of our existing passive treatment systems below: