^tDS%
o
I NONPOINT SOURCE SUCCESS STURY
Treatment of Mine Drainage Restores Longs Run
Waterbody Improved Metals and acidity in d^hareesfrom abandoned coal mines impaired
Pennsylvania's Longs Run, prompting the Pennsylvania Department of
Environmental Protection (PADEP) to add 5.3 miles of the mainstem stream to the state's Clean Water
Act (CWA) section 303(d) list of impaired waters in 1996. Project partners installed 15 passive treatment
systems to address the impacts of the mine drainage discharges entering the stream. Water quality and
aquatic habitat was restored, allowing PADEP to remove the entire 5.3-mile segment of Longs Run from
the list of impaired waters in 2014.
Problem
The Longs Run watershed drains approximately 4.8
square miles in Broad Top Township, Bedford County,
in southcentrai Pennsylvania (Figure 1). This watershed
is 91 percent forested but has experienced significant
impairments from abandoned mine drainage (AMD)
dating back to the 1800s. Nonpoint source runoff from
these AMD discharges delivers high metals and acidity
loads to Longs Run.
A stream survey conducted by PADEP in 1980 indi-
cated that Longs Run was a degraded aquatic ecosys-
tem with depressed aquatic life due to AMD impacts.
As a result, PADEP included 5.3 stream miles of the
main stem of Longs Run on the state's CWA section
303(d) list of impaired waters in 1996 for not meet-
ing the aquatic life designated use due to elevated
levels of metals and acidity delivered through AMD.
Broad Top Township conducted an assessment of the
AMD discharges in Longs Run in 2000 to diagnose the
chemical and physical characteristics of the problem
and prioritize treatment.
Using the assessment data, project partners devel-
oped an AMD remediation plan in 2001. This plan was
updated in 2005 to include treatment implemented
since 2001, as well as to reprioritize needs. PADEP
developed a total maximum daily load (TMDL) in 2003
to serve as a pollution diet for the Longs Run water-
shed. The TMDL set limits for metals (aluminum, iron
and manganese) and acidity loads systematically along
stations on Longs Run. These limits, which differ per
station based on the site-specific existing pollutant
loads, served as goals for remediation.
*4 Raystown Branch
Juniata River
Legend
Longs Run
Watershed
Streams
— Nonattaining
—Unassessed
• Sample Points
I I Watershed
Boundry
Figure 1. Longs Run is in south-central Pennsylvania.
Project Highlights
Project partners analyzed the AMD discharges in the
Longs Run watershed and developed a remedia-tion
plan and TMDL. To help achieve TMDL targets,
partners designed and constructed passive treatment
systems to reduce metals and neutralize acidity in the
AMD discharges while improving the water quality and
aquatic habitat of Longs Run (Figures 2 and 3). When
the water comes into contact with limestone the pl-l
levels are raised, which in turn helps neutralize the
acidity and allows dissolved metals to precipitate out
of solution in a controlled environment (outside of the
stream ecosystem).

-------
F igure 2. Before project implementation. AMD flows
emerging from a seep in the hillside caused erosion
and carried pollutants. (Photos by Skelly and Loy, Inc.)
Figure 3. At site LR0-D14, AMD flows through an open
limestone channel passive treatment system and into a
small aerobic wetland before discharging to Longs Run.
Results
In 2011, after remediation, PADEP performed aquatic
habitat assessments on Longs Run to quantify the
recolonization of benthic aquatic life (macroinver-
tebrates, or "bugs") in the waterway. These data
showed an Index of Biotic Integrity (IBI) value of 78.3,
exceeding the minimum IBI score of 63 that indicates a
sustained and healthy aquatic ecosystem. On the basis
of these data, PADEP removed the entire 5.3-mile seg-
ment of the main stem of the Longs Run (PA7899) from
the list of impaired waters.
Project partners attribute the delisting of this stream
segment to the passive treatment systems installed
to address the AMD discharges in this watershed. Pre-
treatment concentrations of metals and acidity at the
mouth of Longs Run were brought below the TMDL
imits post-treatment, attaining the goals of the TMDL
(Table 1).
Table 1. Data collected at the mouth of Longs Run show the
TMDL limits and the sample results for the pollutants of
concern before and after treatment.
Longs Run
monitoring
Aluminum
(mg/L)
Iron
(mg/L)
Manganese
(mg/L)
Acidity
(mg/L)
Before treatment
0.34
2.75
0.58
8.27
TMDL limits
0.20
0.80
0.55
1.41
After treatment
0.05
0.05
0.03
0.00
Of significance, while metals were beneficially
reduced by an order of magnitude, hot acidity was
completely neutralized post-treatment. This indicates
water quality had become net alkaline, a necessary
step toward the reestablishing a stable and robust
aquatic ecosystem. It should also be noted that the
otherwise pristine nature of the Longs Run watershed,
being 91 percent forested, positively contributed to
its rapid recovery post-AMD treatment. Once Longs
Run returned to its natural background chemistry
and alkalinity, macroinvertebrates were able to drift
downstream from healthy refugial tributaries to readily
recolonize the restored main stem.
Partners and Funding
Broad Top Township, Bedford County Conservation
District, the engineering firm of Skelly and Loy,
Western Pennsylvania Coalition of Abandoned Mine
Reclamation, U.S. Office of Surface Mining and PADEP
partnered to address the water quality problems in
the Longs Run watershed. Broad Top Township was
awarded $30,000 in an AMD Watershed Assessment
Grant from PADEP to collect data on the AMD dis-
charges in the watershed. The township was awarded
$140,079 in Pennsylvania Growing Greener funds in
2002 to treat half the AMD discharges and another
$227,619 in CWA section 319 funds in 2003 to treat the
remaining discharges.
' 0 '
%
\
% /
PROl*-
S
o
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA 841-F-17-0010
September 2017
For additional information contact:
Donna Wagner
Pennsylvania Department of Environmental Protection
717-772-5173 • donnawagne@pa.gov

-------