Bear Creek Project Overview
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Coal Mining in the Bear Creek and Wiconisco Creek Watersheds

The upper part of the Wiconisco Creek Watershed, which includes Bear Creek, lies in the extreme southwest section of the anthracite coalfields of Pennsylvania. From the mid-1800’s until the 1930’s, the region encompassing the Bear Creek Watershed and the upper half of the Wiconisco Creek Watershed were heavily mined using both strip and deep mining methods. 

While virtually nonexistent today, anthracite coal production from mines in Dauphin County during the year 1930 alone was nearly one million tons.  Underground mining operations worked more than 20 anthracite beds of the Pottsville and Llewellyn formations. The underground mines ranged in size from small punch mines along the coal outcrops to large operations such as the Williamstown Mine in the Lykens Valley No. 4 and No. 5 veins which extend as deep as 2,200 feet below sea level. Surface mining activity was reportedly generally limited to the southern flank of Bear Mountain and along crop areas of Short Mountain.

When mining activity in the Bear Creek Watershed ceased in the mid twentieth century, the complex of mine workings became flooded due to seepage from groundwater and also due in part to surface water finding its way down to the workings from the surface through “cropfalls”. Cropfalls or sinkholes are formed on the surface where the underlying tunnels have collapsed.

What is
AMD?
Why is AMD
a concern?
The Need for Remediation
What is Passive Treatment?
Resource Recovery

Recent developments in the field of resource recovery are proving fruitful for the future use of this iron sludge.  Sludge, once removed, can be marketed for use as pigment for paints, stains and other applications. The Dauphin County Conservation District along with the Eastern Pennsylvania Coalition for Abandoned Mine Reclamation, the Wiconisco Creek Restoration Association, and other project partners are currently investigating the potential for the use and marketability of iron sludge from the abandoned mine discharges at Bear Creek.

What is Passive Treatment?

Unlike active treatment for AMD, passive treatment does not require continuous manpower, resources or chemical inputs. Rather, passive treatment takes advantage of naturally occurring chemical or biological processes to cleanse contaminated mine waters. In most passive systems, aerating the water in large ponds or wetlands helps the dissolved metals in mine water undergo certain chemical changes, which allow the metals to settle out as sludge. Generally, periodic removal of the sludge is the only large-scale maintenance that needs to be done.

For Phase I of the Bear Creek project, three settling ponds were constructed to provide passive treatment of the AMD-contaminated water from the mine tunnel entrance. Click here for more information about Phase I of the project.

The Need for Remediation

More than 2,500 river and stream miles in Pennsylvania are reported as impaired by Abandoned Mine Drainage (AMD). Stream impairment, or the inability of a stream to sustain healthy aquatic life is the result of pollution such as AMD.

The area within the Bear Creek Watershed was extensively deep mined for over 100 years and the coal fields have been largely depleted of the easily obtainable coals. As a result, the mines have been abandoned and have been discharging water polluted with metals (primarily iron) since the 1930’s. Most of the mining in the Bear Creek Watershed occurred well before modern reclamation practices and requirements so little to no reclamation or remediation activities were completed upon mine closures. 

The iron in the polluted mine water settles out in the creek and smothers the stream bottom , resulting in the inability of Bear Creek to support aquatic life.

The Dauphin County Conservation District, the Wiconisco Creek Restoration Association and other organizations recognize the value in clean streams and are partnering to remediate the AMD impacts on Bear Creek. 

The long-term goal of this effort is to restore Bear Creek to a healthier state by installing passive treatment systems to trap the iron sediment before it reaches the creek. 

The Bear Creek Project will be the first recorded effort to treat the AMD entering Bear Creek and will likely be the springboard for future AMD remediation projects within the entire Wiconisco Creek Watershed.

The broader positive impacts of AMD remediation efforts  in the Bear Creek and Wiconisco Creek Watersheds are many. These positive impacts include improved fisheries, increased tourism, and an improved local economy.

Broad-based partnerships like those represented in the Bear Creek Project, continue to be the most effective way for addressing the widespread degradation caused by AMD in the Anthracite region.

Why is AMD a concern?

The effect of a metal such as Iron, can be seen as Iron Hydroxide or “yellow boy” depositing on the stream bottom. While elevated levels of dissolved metals can be toxic to aquatic life, the Iron Hydroxide or “yellow boy” actually smothers the stream bottom along with the insects and other aquatic invertebrates, disrupting the food chain for larger animals. In addition to the impacts on the natural environment, man’s use of the streams is also limited. Extra treatment is required to make the water drinkable. Industrial uses and agricultural uses for livestock or irrigation are limited. In addition, recreational use and the aesthetic value are impacted.

What is AMD?

Abandoned Mine Drainage (AMD) is water that has become contaminated as a result of passing through the underground voids created by underground mining, or it can occur by water passing through coal refuse left on the surface. AMD contamination can vary a great deal from site to site, since its formation is dependent upon a variety of factors. AMD is created when water comes in contact with certain reactive minerals that have been exposed through mining activities below the ground. 

The mineral responsible for much of the AMD formation is Iron Pyrite, also known as fool's gold. Pyrite reacts when it comes in contact with water and oxygen. In actuality a series of chemical reactions occur to form contaminated water. The bottom line of these reactions is the generation of acidity and Iron Hydroxide. 

The acidity generated by these reactions also dissolves other minerals and metals such as Aluminum and Manganese. As a result, AMD may contain a variety of pollutants.

However, not all AMD is acidic. In some places, naturally occurring limestone may be present in the underlying rock strata. The limestone acts to neutralize the acidity and the discharge may then become alkaline. These alkaline discharges may also contain high levels of dissolved metals.

Abandoned Mine Drainage Treatment
at Bear Creek near Wiconisco, PA
Bear Creek flowing into Wiconisco Creek outside of Wiconisco, PA

AMD-contaminated water discharged from the mine entrance to the Lykens Valley Water Level Tunnel
Rocks and soil coated with "yellow boy" sludge.
Click here to read the US Geological Survey's report on Bear Creek.

1451 Peters Mountain Road Dauphin PA 17018 phone: 717-921-8100