For several decades, acidic Abandoned Mine Drainage (AMD) from the Silver Creek mine flowed into the Schuylkill River, polluting it with metals and lowering the water’s pH level. Partnering with Rettew Associates, Inc., SHA installed a passive treatment system that includes five pools. The AMD water is collected in the scour pool, allowing it to slow down. As it leaves the scour pool, the water is spread across a wide area in a sheet flow. As it passes through the second and third settling ponds, the metals drop out of the water, the water then flows thru two shallow wetland cells before reentering Silver Creek. This system will treat approximately 1,200 gallons of water per minute over the course of 20 years.
Location: New Philadelphia, PA Source of Funding: EPA 319 Grant Date of Completion: July 2010 Leading Organization: Schuylkill Headwaters Association Cost: $858,402
The Glendower Pond Breach restoration project restored a stream stretch along the West Branch of the Schuylkill River, preventing legacy sediment from entering the stream and negatively affecting water quality. Several years prior, heavy flooding caused the pond to breach, which diverted water that was once piped into the stream into a newly carved and eroded channel. The water was flowing directly through a small valley filled with coal sediment causing further erosion.
This project involved redirecting the stream, through a stabilized waterway, back into its original stream channel. Eroded areas created by the flood were filled with material from the site. In order to stabilize banks and prevent further erosion, all disturbed and eroded areas were sloped and vegetated.
Location: Heckscherville Valley Source of Funding: Grant from the Schuylkill River Restoration Fund, AMD / AML Reclamation Award from EPCAMR, Anthracite Independent Power Producers Association (ARIPPA) as a cash match, in-kind donation from Reading Anthracite in the form of large rip-rap stone, which involved over 1,700 tons of stone valued at over $31,000. Date of Completion: December 2010 Leading Organization: Schuylkill Headwaters Association Cost: $125.035
Pine Knot Tunnel Study
This project entailed locating recharge sites of the Pine Knot mine pool. Utilizing funds from the Schuylkill Watershed Initiative Grant, the Pine Knot Tunnel project provided a conceptual design and feasibility study for remediation and mitigation of water pollution attributed to AMD at a collection of sites. Potential project areas were identified, and treatment and diversion project designs were implemented. As part of the study, the USGS is monitoring flow and hydrology to provide critical insight about how the Pine Knot Tunnel system drains. This monitoring has continued beyond the study period.
Location: Heckscherville Valley Source of Funding: EPA TWIG Grant Date of Completion: 2007 Leading Organization: Schuylkill Headwaters Association Cost: $134,996
Abandoned Mine Drainage (AMD) from the Pine Forest Mine used to flow into Mill Creek discharging aluminum, iron, manganese, and acidity. Because it is a tributary of the Schuylkill River headwaters, the AMD would then flow into the Schuylkill River.
Using funds from the Schuylkill Watershed Initiative Grant, SHA installed an anoxic limestone drain (ALD), which is a buried ditch full of limestone. As mine water flows through the drain, the limestone dissolves and increases the alkalinity and pH levels, decreasing the water’s acidity. When exiting the drain, the treated water comes into contact with oxygen as it cascades over rocks and is captured in settling ponds. These ponds keep collected water calm for a period of time, allowing the metals to sink to the bottom before the water flows on to the Schuylkill River. The ALD at Pine Forest now removes up to 316lbs of iron per day from the Schuylkill River.
Location: Near St. Clair, PA Source of Funding: EPA 319 Grant, OSM Grant, TWIG Grant Date of Completion: September 2007 Leading Organization: Schuylkill Headwaters Association Cost: $801,867.19
Reevesdale 2 South Dip
Every minute, the Oxic Limestone Drain (OLD) system at the Reevesdale South Dip Tunnel treats approximately 900 gallons of Abandoned Mine Drainage (AMD) that would otherwise flow directly into Wabash Creek, a tributary of the Little Schuylkill River. This treatment reduces the amount of aluminum, iron, manganese, and acidity present.
OLD’s are buried limestone ditches into which AMD water is directed. As it passes through, the water dissolves limestone, increasing the alkalinity and pH levels of the water. This lowers the acidity. Oxygen in the AMD water causes iron hydroxides to form and clog the system, therefore, OLD systems need to be flushed regularly.
Water flushed from the drain is held in the wetland retention ponds until metals collect at the bottom for subsequent removal. Despite the installation of a flush pipe network, accumulations of metals in the limestone bed quickly decreased the system’s effectiveness. In the disastrous floods of 2006, the overwhelmed system failed completely, requiring extensive repairs in 2008.
The repaired system includes a reconfigured water-flow path to increase exposure to the limestone surface and decrease the clogging potential. AMD treatment systems are a new technology that requires tailoring to individual site characteristics. The lessons learned from the Reevesdale system provide important information for future AMD design and installation.
Location: Reevesdale, PA Source of Funding: Schuylkill Watershed Initiative Grant Date of Completion: 2006-2008 Leading Organization: Schuylkill Headwaters Association Cost: $226,196
This project entailed installing a passive treatment system for the water flowing from the Bell Colliery Drift. As is the case with many abandoned mines, water gathers in the underground tunnels where it “picks up” metals and, eventually, flows into the Schuylkill River. Such discharges are known as Abandoned Mine Drainage (AMD). In addition to the metals themselves having an undesirable effect on the river, Bell’s AMD water is acidic.
With the new treatment system, water now first flows through large cells filled with limestone, which decreases the water’s acidity and makes it easier for the metals to drop out of the water. Next, the water flows into a settling pond and a wetland cell, both of which catch the resulting metal sludge before it can be carried into the Schuylkill River.
Location: Near Mary D, PA Source of Funding: EPA 319 Grant Date of Completion: 2004 Leading Organization: Schuylkill Conservation District Cost: $342,940
In Norwegian Township, a large underground area drains into the West Branch of the Schuylkill River. Before 2002, this included Abandoned Mine Drainage (AMD), which negatively impacted the area’s eco-system. The Reading & Blue Mountain Northern Railroad Company leased a nearby floodplain to SHA so that they and Rettew Associates, Inc. could build a passive treatment system that would prevent this from happening. The AMD now flows through an intake structure to a settling pond, then a wetland treatment cell, both of which allow the offending metals to drop out of the AMD water. Once treated, the water flows back to the river via an outfall structure. Additionally, a two-foot high berm was placed around the system’s perimeter in order to prevent flooding damage.
Location: Norwegian Township, PA Source of Funding: EPA 319 Grant Date of Completion: 2002 Leading Organization: Schuylkill Headwaters Association Cost: $149,869.50
As water passes through the former Otto mine, AMD drains into Muddy Branch Creek, a tributary for the West Branch of the Schuylkill River. In order to clean the water, SHA built a treatment system to catch the AMD water before it enters Muddy Creek. As the water flows down hill towards the creek, stop logs divert it into an oxidation pond. Mechanical aerators add air to the water which drives off excess carbon dioxide from the water increasing pH. This process aids in accelerating the iron precipitation out of the water column.
To encourage all three of these processes, two five-foot long turbidity curtains hang vertically from the surface, slowing down the water and forcing it to flow in a widespread sheet-like formation instead of simply rushing through as a stream. The water is further filtered as it travels through two wetlands and before flowing into Muddy Creek.
The treated water initially was planned to go through a limestone drain in order to lower the temperature, making the water more favorable for trout. Unfortunately, the amount of iron in the water was more than anticipated and the drain has since been clogged. There is no flushing mechanism within this treatment system that could prevent or repair this, so the water now bypasses the drain. Unlike some AMD water, the discharge from Otto is not acidic, so limestone is not needed to raise the pH level.
Location: Branchdale, PA Source of Funding: EPA 319 Grant Date of Completion: 2005 Leading Organization: Schuylkill Headwaters Association Cost: $432,220
Mary D Ballfields
At the Mary D borehole, water flowed from mines into the Schuylkill River, polluting the river with abandoned mine drainage (AMD). SHA sought to create a passive treatment system that would allow the metals to naturally drop out of the discharge into a wetland before reaching the river.
Unfortunately, the only viable site for the wetland was the Mary D Ball Field, the town’s only recreational site. Using nearly $600,000.00 in grants and 10 acres of donated abandoned mine land, SHA and Rettew Associates, Inc. were able to build The Mary D Fire Company Sports Complex, which includes a regulation little league field as well as an all-purpose field, an ice skating pond and a walking trail. The construction of this new recreational complex has allowed the construction of the passive treatment system to go forward.
Location: Mary D, PA Leading Organization: Schuylkill Headwaters Association
Along Valley Road lay several areas where underlying abandoned mine workings have caused the ground to collapse. Before this project was completed, these areas, commonly known as crop falls, would fill with rainwater and stormwater runoff and flow into the mine workings below, recharging the Pine Knot minepool. Eventually, this tainted water would flow out of the Pine Knot Discharge and into the Schuylkill River. In an effort to prevent this, the Schuylkill Headwaters Association diverted the path of the rainwater and stormwater runoff directly to the West Branch of the Schuylkill River away from the cropfalls preventing the water from becoming polluted.
Location: Mackeysburg/Heckscherville Valley Source of Funding: William Penn Foundation Cost: $161,450