NONPOINT SOURCE SUCCESS STORY
Reclaiming Abandoned Mine Lands Reduces Impact of Acid Mine
Drainage in the Bennett Branch Basin
Waterbodies Improved
Acid mine drainage (AMD) degraded water quality in
Pennsylvania's Bennett Branch Sinnemahoning Creek. As
a result, Pennsylvania added the stream to its 1996 Clean Water Act (CWA) section 303(d) list
of impaired waters for high metal concentrations. To address the AMD problem, significant
partnerships were developed with the mining industry to accomplish mine reclamation and to
use recoverable coal and waste coal resources. Water quality in Bennett Branch has dramatically
improved after restoration, with decreased metal concentrations and increased alkalinity.
Problem
Bennett Branch Sinnemahoning Creek (Bennett Branch)
is a 38-mile-long wild and scenic river in Clearfield, Elk
and Cameron counties in north-central Pennsylvania
(Figure 1). Bennet Branch flows into the Susquehanna
River, which empties into the Chesapeake Bay.
Restoring Bennett Branch is a priority because the
watershed contains much of the state's growing elk
population and also has enormous potential for growth
in tourism and other outdoor recreation.
Coal mining in the area began in the late 1800s.
Extensive underground mining was underway by the
early 1900s; surface and strip mining began in the
1940s. Both continue to a limited extent today. Many
established mines were eventually abandoned and
left unclaimed. Drainage from these abandoned mine
lands contribute dissolved metals to Bennett Branch.
The Pennsylvania Department of Environmental
Protection (PADEP) first designated Bennett Branch
as impaired for metals in 1996, and placed much of
the stream on the CWA section 303(d) list of impaired
waters. PADEP conducted additional sampling in the
early 2000s. At present, 19 segments of Bennett
Branch are on the impaired waters list.
In July 2004, PADEP and the Bennett Branch Watershed
Association completed a "Watershed Snapshot" study
to identify critical areas of AMD pollution. The study
identified three distinct watershed drainage areas in
need of AMD treatment—Hollywood, Dents Run and
Caledonia. The Hollywood Area tributaries collectively
contributed 41 percent of the acid load to Bennett
i/565 The National Map: National Boundaries Dataset, 3D
Elevation Program, Geographic Names Information System,
National Hydrography Dataset, national Land (over
Database, National Structures Dataset, and National *"T
Transportation Oataset; US. (ensus'Bureau - TlGER/Line
A Sampling Station (WQN0439)
Bennett Branch HUC 12s
Figure 1. Bennett Branch flows through coal mining
lands in north-central Pennsylvania.
Branch, while Dents Run and Caledonia Run contributed
27 and 24 percent, respectively.
Total maximum daily loads (TMDLs) were approved
for Bennett Branch in 2009 and consisted of load
allocations for iron, manganese, aluminum and acidity
to seven sampling sites on Bennett Branch (BBSC6,
DENT 1.0, BBSC5, BBSC4, BBSC3, BBSC2 and BBSC1).
The TMDLs require aluminum and iron concentrations
to be below 0.75 and 1.5 milligrams per liter (mg/L)
respectively, and for pH values to be between 6 and 9.
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Figure 2. Bennett Branch water quality data.
Project Highlights
In 1998 the Bennett Branch Watershed Association
formed to begin the restoration work needed on
Bennett Branch to restore it to its pre-mining condi-
tion. In each of the three distinct areas with severe
AMD damage, the partners implemented projects that
focused on reclaiming abandoned mine lands.
In 2007 construction began on the Hollywood
Treatment Facility, which has been operational since
July 1, 2012. The facility dramatically improves water
quality by treating an average of 2.7 million gallons
per day of mine drainage from 21 separate discharges
originating in four different underground mine com-
plexes (Table 1).
Table 1. Average pump station intake water quality
compared to treatment plant effluent
Sampling
Location
At intake
In effluent
Water Quality Averages
pH
3.27
7.54
Total Iron (mg/L)
47.7
0.98
Aluminum (mg/L)
17.75
0.44
In addition, a re-mining operation was conducted
at Mills Run, a tributary to Bennett Branch. In the
Caledonia Area, PADEP completed projects that
reclaimed more than 100 acres of abandoned surface
mining areas. At Dents Run, a partnership was formed
with the active mining industry. This partnership pro-
vided a low-cost source of alkaline material for alkaline
addition and passive treatment.
Figure 3. Dents Run (2009), after treatment of AMD
seeps in the watershed (see inset photo).
Results
As of March 2009, water quality in Bennett Branch
had dramatically improved. Water samples collected
after 2012 in Bennett Branch below the Hollywood
treatment plant show pH levels in the range of 6.9
to 7.3, iron levels between 0.5 and 1.3 mg/L, and
aluminum levels between less than 0.5 and 0.7 mg/L
(Figure 2). Dents Run became net alkaline for the
first time in over a century, eliminating 27 percent
of the acid load to Bennett Branch (Figures 2 and 3).
Monitoring data show water quality improvement in
five Bennett Branch segments: PA2800 (4.9 miles),
PA7999 (23.1 Miles), PA8000 (8.6 miles), PA9804
(8.9 miles), and PA3687 (3.0 miles).
Over 800 acres of new rangeland have been created
for Pennsylvania's growing elk population through
reclamation and re-mining efforts within the water-
shed. The projects completed to date have reclaimed
or treated 390 acres of abandoned mine lands through
alkaline addition, which significantly reduced AMD
within the watershed. Construction of the Hollywood
treatment plant eliminated approximately 40 percent
of the acid load to Bennett Branch.
Partners and Funding
The restoration of Bennett Branch was supported by
private, state and federal investments. Overall, more
than two dozen projects have been completed, for
a total cost of approximately $44 million in Bennett
Branch. Of this funding, the private sector contributed
approximately $6.1 million, the PADEP Bureau of
Abandoned Mine Reclamation contributed $34 million,
and the Army Corps of Engineers contributed
$4.1 million.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-16-001J
May 2016
For additional information contact:
Eric E. Cavazza, P.E.
PADEP Bureau of Abandoned Mine Reclamation
ecavazza@pa.gov • 814-472-1844
Richard L. Beam, P.G.
PADEP Bureau of Abandoned Mine Reclamation
ribeam@pa.gov • 814-472-1844
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