surface coal mining impacts on concentration-discharge relationships: identifying spatial and...
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Surface coal mining impacts on concentration-discharge relationships: Identifying spatial and temporal changes in the New River, TN
Jenny MurphyVanderbilt University
USGS TN Water Science Center
George HornbergerVanderbilt University
GSA Annual Meeting, October 12, 2011
MemphisNashville
Tennessee
Knoxville
Oak Ridge
New River
Indian Fork
Watershed boundaryStreamGauging Station / sample siteCoal mining disturbance
New River
Coal Mining in TennesseeLand use cover change
from 1973 to 20001977: SMCRA enacted1980: State program begins1983: “Massive failures”1984: TN federal program begins
(Loveland et al., 2003)
Data Sets
New River Indian Fork2007 2009
1977—1980 1975—1981
Parameters(1) Streamflow (2) Specific conductance (3) Sulfate
(USGS) (This study)
(USGS) (USGS)
Recent
Historic
Methods: Data Analysis
Intra-annual relationships(1) Linear regression on Log(C)-Log(Q) data
Episodic relationships (2) C-Q hysteresis plots
0.1 1 10 100 100010
100
1000
10000
f(x) = 283.1 x^-0.1777R² = 1
f(x) = 378.471696180653 x^-0.245450350207965R² = 0.804782802953823
Log(SpC)-Log(Q)
2007
Power (2007)
Flow (m3/s)
SpC
(uS/
cm)
Results: Linear regression
1976-1982
y = axb
n=68
n= 15-min
New River
Results: Linear regression
Indian Fork
0.01 0.1 1 1010
100
1000
10000
f(x) = 26.2879580409369 x^-1.14619456960979R² = 0.709399510950909
f(x) = 206.001213598993 x^-0.234178001632422R² = 0.271011020736519
Log(SO4)-Log(Q)HistoricPower (Historic)
Flow (m3/s)
Sulfa
te (m
g/L)
n=115
n=120Recent
y = axb
“Background” sulfate
Dickens et al 1989
Methods: C-Q plots
After Evans & Davies 1998
Discharge
Conc
entr
ation
0 10 20 30 40 50
2.5
2.0
1.5
1.0
0.5
0
Total discharge
Non-impacted water
Impacted water
Event water
Methods: C-Q plots
Evans & Davies 1998
0 20 40 60 80
100
90
80
70
60
50
Discharge
Conc
entr
ation
0 20 40 60 80
100
90
80
70
60
50
DischargeCo
ncen
trati
on0 20 40 60 80
100
90
80
70
60
50
Discharge
Conc
entr
ation
0 20 40 60 80
100
90
80
70
60
50
Discharge
Conc
entr
ation
0 20 40 60 80
100
90
80
70
60
50
Discharge
Conc
entr
ation
0 20 40 60 80
100
90
80
70
60
50
DischargeCo
ncen
trati
on
(a) CE > CNI > CI (b) CE > CI > CNI (c) CNI > CE > CI
(d) CI > CNI > CE (e) CI > CE > CNI (f) CI > CE > CNI
C1 C2 C3
A1 A2 A3
Results: C-Q plots
0 20 40 60 80 100 120 140 160100
150
200
250
300
350
Jan 5-7
Mar 15-20
Apr 4-7
Aug 4-5
Oct 24-28
Nov 15-16
Nov 26-Dec 2
Flow (Q)
SpC
(uS/
cm)
New River 2007
0 20 40 60 80 100 120 140 160100
150
200
250
300
350
Jan 5-7
Mar 15-20
Apr 4-7
Aug 4-5
Oct 24-28
Nov 15-16
Nov 26-Dec 2
Flow (Q)
SpC
(uS/
cm)
Results: C-Q plots
~25 m3/s
New River 2007
0 20 40 60 80 100 120 140 160100
150
200
250
300
350
Jan 5-7
Mar 15-20
Apr 4-7
Aug 4-5
Oct 24-28
Nov 15-16
Nov 26-Dec 2
Flow (Q)
SpC
(uS/
cm)
Results: C-Q plots
~25 m3/s
New River 2007
Results: C-Q plots
0.1 1 10 1000
50
100
150
200
250
300
350
Sept 18-19
Sept 26-27
'Oct 9
Oct 31-Nov 1
Oct 15-16
Flow (Q)
SpC
(uS/
cm)
Indian Fork 2009
Results: C-Q plots
0.1 1 10 1000
50
100
150
200
250
300
350
Sept 18-19
Sept 26-27
'Oct 9
Oct 31-Nov 1
Oct 15-16
Flow (Q)
SpC
(uS/
cm)
Indian Fork 2009
Results: C-Q plots
0.1 1 10 1000
50
100
150
200
250
300
350
Sept 18-19
Sept 26-27
'Oct 9
Oct 31-Nov 1
Oct 15-16
Flow (Q)
SpC
(uS/
cm)
Indian Fork 2009
Conclusions1) Temporal: Linear regression• Minimal change in New River• Significant change in Indian Fork
2) Spatial: C-Q plots• Threshold (25m3/s) for C-Q
response in New River• No threshold in Indian Fork• Mixing modelsNew River (7% disturbed)
3 component mixingIndian Fork (23% disturbed)
2 component mixing
New River
Clea
r For
k
Big South Fork of the Cumberland River
Conclusions1) Temporal: Linear regression• Minimal change in New River• Significant change in Indian Fork
2) Spatial: C-Q plots• Threshold (25m3/s) for C-Q
response in New River• No threshold in Indian Fork• Mixing modelsNew River (7% disturbed)
3 component mixingIndian Fork (23% disturbed)
2 component mixing
New River
Clea
r For
k
Big South Fork of the Cumberland River
Questions?
AcknowledgementsVanderbilt University Environmental and Civil Engineering Lab
Vanderbilt University Earth and Environmental Science departmentBig South Fork National Recreation Area
Tennessee Water Science CenterGSA student research grant