Acid Mine Drainage

Acid mine drainage is just one of the many problems of AML. Mines fill up with water and spill over into local watersheds, or water seeps through former mining sites contaminating the water. 

 

The EPA classifies AMD as being characterized by one or more of the following:

• Low pH ( high acidity)
  
• High metal concentration (usually iron, aluminum and manganese)
  
• Elevated sulfate levels 
  
• Excessive suspended solids 

Acid mine drainage can cause streams to die with no active fish, or insect life, and stunted plant growth. AMD can also lead to orangish colored water (with the iron), and sometimes even metallic (with the aluminum). 

Measures are being taken by local groups in conjunction with the EPA to clean up local watersheds. These projects are know as Abandoned Mine Drainage Abatement and Treatment plans (AMDAT). 

Raccoon Creek Watershed

"The Raccoon Creek Watershed Partnership is neat. It's a non-profit and agency partnership, but it's not an adversarial relationship it is a collaboration to improve the watershed's quality."- Ben McCament, Raccoon Watershed Coordinator. 

Raccoon Creek Watershed Partnership originally began in the 1980s with concerned citizens. In the early 90s the citizen group paired up with state agencies to take action. Since the partnership formed they have completed 10 projects from $7 million in grant funding.

The partnerships main focus is to restore the main stem of Raccoon Creek, as well as the main stem of Little Raccoon Creek. In hopes of restoring the creek the partnership divided the area into three sections, the headwaters, middle basin, and Little Raccoon Creek. Each section has multiple projects to restore the water as it enters the main stem.

Whenever beginning a new project lots of monitoring and studying takes place, and all treatment options are considered. They average 350 water samplings a year, as well as  fish monitoring and habitat monitoring, totally about  2-3 months of observation.

"We have limited resources so we want to make the best choice, which will help the stream with the most recovery," said McCament. 

The idea way to combat AMD is to fill in underground mines so water can no longer seep through them. When that isn't an option due to money and resources, there are a variety of treatments the Raccoon Creek Partnership uses. 

One the partnership treat AMD is by building steel slags. A pond will is built containing steel slag ( a byproduct of mating steel) above the source of acid mine drainage. This decreases the waters acidity before the AMD point. This will neutralize the water once the two combine before the stream runs into the creek. 

Another similar treatment is limestone ponds. The pond filled with limestone will be placed below a contaminated area and the water will flow it decreasing in acidity. The water will then flow through a second pond where clumped metals will be deposited before the stream flows again towards the main stem. 

Other treatment methods the partnership employs are wetlands- the biological activity with in then decreases the water acidity. The final treatment employed by Raccoon Creek is a doser. The doser is the only active treatment in Ohio and it involves directly adding chemicals to the water to neutralize it. 

"All streams are worth restoring and protecting. Raccoon Creek is one of the largest creeks (actually a river) with lots of resources and public land. It has a large potential for recover. The creek hasn't been completely destroyed," said McCament. 

A stream is considered restored when it meets the EPA bio criteria for water.
McCament estimates that the partnership has about a dozen more priority projects, totally at least another 20 years of work and $10 million. 

*Raccoon Creek only deals with abandoned mines, mines before 1977, mines since then have had to take care of cleaning up after themselves. 

Other Local AMDAT Projects

Federal Valley Watershed Group 
Monday Creek Restoration Project 
Sunday Creek Watershed

This is a picture of  the Cardondale Doser the only active treatment used in the state of Ohio. It's located in the headwaters of the creek. Each day it dispenses 1/2 ton of chemicals. It holds a total of about 7 tons.
Dissolved aluminum in the acidic water precipitates as a solid flocculent when the water from the mine is exposed to oxygen. This chemical reaction typically occurs when the pH is above 4.5 (Raccoon Creek Partnership description.)

The upper Oreton Valley is blocked by abandoned surface mile spoil. The AMD water then flows down into the lower wetland before entering Pierce Run. Some of the Iron is store in this wetland but the majority is flushed into Pierce Run. ( Raccoon Creek Partnership description.)

(Information from Ben McCament Raccoon Watershed Coordinator, and from the EPA site. Pictures courtesy of the Raccoon Creek Partnership.)