Section 319
NONPOINT SOURCE PROGRAM SOCGESS STORY
Treating Acid Mine Drainage Improves Cherry Cree
WatPrhndv Imnrnvpd Abandoned coal mines contributed high levels of acidity and
metals to Maryland's Cherry Creek, which flows into Deep
Creek Lake. As a result, the Maryland Department of the Environment (MDE) added the Deep
Creek Lake watershed, including Cherry Creek, to the state's 1996 Clean Water Act (CWA)
section 303(d) list of impaired waters for pH. Acid mine drainage (AMD) mitigation projects
were implemented in Cherry Creek, which now consistently meets the total maximum daily
load (TMDL) goal for pH. In addition, acidity, iron and aluminum levels have declined.
Problem
Western Maryland's Cherry Creek begins near
Savage River State Forest, flows about eight miles
through a 7900-acre watershed, and empties into
Deep Creek Lake (Figure 1). Outflow from the lake
enters the Youghiogheny River, which is in the
Ohio River Basin. The Cherry Creek watershed is
composed of 69 percent woodlands and 12 percent
wetlands; the remainder is mixed agriculture and
developed lands. Deep Creek Lake is a manmade
recreational impoundment that is popular for fishing
and boating.
The name Cherry Creek can be traced to the water-
body's deep reddish color, which was historically
caused by bog tannins from sphagnum wetlands.
These wetland complexes include coniferous forest
and marshes, and they contribute natural organic
acidity to the stream.
In the 1920s Cherry Creek was a natural trout
stream and the site of a trout-rearing station.
During the next several decades, AMD associated
with coal mining increased. In 1957 a large fish kill
caused by low pH brought an end to trout stock-
ing in Cherry Creek. A 1973 study reported that
almost the entire main stem of Cherry Creek was
severely or moderately polluted by AMD. That study
also estimated that one-fourth of the acid load in
the stream is derived from mines; the rest is from
natural sources. In the 1980s it was estimated that
Cherry Creek was the source of half the acidity
entering Deep Creek Lake.
Before project implementation, AMD generally
caused the in-stream pH to fall to between 4.0
and 4.3,with a pH as low as 3.2 during periods of
low flow. To address this impairment, the TMDL
Cherry Creek Watershed
Deep Creek
Deep Creek Lake
Lake Watershed
Figure 1. The Cherry Creek watershed is in western Maryland.
approved for Cherry Creek calls for a pH of 4.6 or
higher. That level takes into account the naturally
low pH arising from the sphagnum wetlands that
characterize Cherry Creek.
Project Highlights
Between 1986 and 1989, MDE created a series of
treatment wetlands to help reduce AMD impacts in
the Cherry Creek watershed. The Department con-
structed additional AMD treatment systems between
1998 and 2001, including successive acid treatment
systems and more treatment wetlands. Several
commercial AMD treatment systems were also
introduced, including an Aluminator® (a successive
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Figure 2 . Partners installed a
successive alkalinity-producing
system at the Everhart project site.
Figure 3 . Partners installed a
limestone doser adjacent to
Cherry Creek.
alkalinity-producing system
that includes a treatment
cell designed to precipitate
aluminum while keeping
iron in a soluble form), a
Pyrolusite®cell (bioremedia-
tion using limestone and
bacteria to remove metals),
and a Boxholm® doser (a
system that introduces lime
to the water at a given rate).
(See Figures 2 and 3.) The
Cherry Creek mitigation
effort used approximately
6,760 tons of limestone, not
including the lime used for
the doser.
Results
In-stream sampling con-
ducted after AMD imple-
mentation (2003-present)
shows that pH is gener-
ally greater than 6.0 and
is always greater than 5.2,
meeting the TMDL goal (a
pH of 4.6 or greater). Data
also showthat individual
AMD treatment sites have
significantly reduced
concentrations of pollutants
while also increasing alkalin-
ity (Table 1).
Fish surveys show that fish populations have
increased. In 1971 only three species of lake fishes
were found in Cherry Creek, and they were found
only near the confluence of the creek with Deep
Creek Lake. In 2004, after implementation of AMD
mitigation, a survey found seven fish species in
the stream. The survey report stated that rainbow
trout, brown trout and smallmouth bass were com-
mon enough to support some recreational fishing
and that the range of several fish species extended
from the stream mouth upstream about 1.5 miles
to the vicinity of the lime doser. According to the
2004 survey report, fish have not progressed far-
ther upstream because of a complete blockage by
an old mill dam and inflowfrom a small unnamed
tributary, which might be contributing additional
AMD. A 2012 analysis of all benthic macroinverte-
brate data for Cherry Creek found that the Benthic
Index of Biological Integrity might have improved,
but the stream's condition continues to be classi-
fied as poor overall. The sources of this continuing
biological impairment are believed to include AMD.
Partners and Funding
MDE's Abandoned Mine Lands Division was the
primary implementer of the Cherry Creek AMD
mitigation projects. The total capital cost for the
restoration project was $496,000 over 15 years;
funds were provided by the State of Maryland; the
U.S. Department of the Interior, Office of Surface
Mining; and the U.S. Environmental Protection
Agency. In addition, the private Sprenger Lang
Foundation paid for the purchase and construction
of the lime doser, which is located on property
owned by the Rock Creek Trust. Funds for operation
and maintenance of the doser ($30,000 annually)
come from the State of Maryland and the U.S.
Department of the Interior. Other partners that
help manage and monitor Cherry Creek include
the Maryland Department of Natural Resources'
Fisheries Service and the University of Maryland's
Appalachian Lab.
Table 1. Monitoring Data for Cherry Creek Project Sites, Before and After Installation of
AMD Treatment (Average)
Project Site
Everhart site
Glotfelty site
Teets site
PH°
Before
3.5
5.3-5.9
3.1
After
6.1
6.9
7.1
Acidity b
Before
300
372
486
After
21
0.0
0.0
Alkalintyb
Before
0.0
N/AC
0.0
After
23
N/AC
106
Ironb
Before
65
111-147
73
After
1.5
0.83
1.2
Aluminum b
Before
4.9
1.5-3.5
37
After
0.1
0.1
0.1
1 In standard units.
' In milligrams per liter (mg/L). ° Not available.
UJ
O
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-13-001A
January 2013
For additional information contact:
Connie Loucks, Maryland Department of the
Environment, Abandoned Mine Land Division
301-689-1461 • cloucks@mde. state, md. us
Ken Shanks, Maryland Department of the Environment,
Watershed Protection and Restoration Program
410-537-4216 • kshanks@mde.state.md.us
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