Transcript coecs.ou.edu

Mine Water Quality Changes
in at the Mayer Ranch
Wetland
Kim Wahnee
Dr. Robert Nairn
Dr. Keith Strevett
REU 2000
Presentation Overview
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General background
Introduction to study site
Research questions
Field and analytical methods
Results
Conclusions
Tri-State Mining District
 Extensive underground lead and zinc
mining (1900-1960s)
 Mine flooding began after cessation of
mining and associated dewatering
 Polluted artesian discharges emerged in
late 1979
 40 square mile site received Superfund
status in 1983
Picher Mining Field of the Tri-State
Mining District
OTTAWA
COUNTY
OKLAHOMA
Mayer Ranch
 Location of first major mine water
discharges; November 1979 in horse
pasture
 At least two major seeps identified
 Mine water characterized by USGS
(1985)
 Extensive volunteer cattail marsh
established in last 20 years
Mayer Ranch Wetland
Meyer Ranch Wetland
Seep A
West
Marsh
Mine drainage marsh
Runoff
Seep B
Research Questions
 What are the chemical constituents of
the mine discharges and surface waters
at Mayer Ranch?
 Is the water quality changing from the
discharges to wetland outflow?
Methods
 Sampled mine water discharges and
surface waters at 8 locations
 In situ measurements
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pH, temperature, alkalinity, dissolved
oxygen, oxidation-reduction potential,
conductivity, turbidity, flow rate
 Metals and anion data
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Ca, Mg, Zn, Fe, Cd, Pb
SO4-2, Cl-, F-, NO2-, NO3-, PO4-3
Comparison to Historical Data
pH
Alkalinity
USGS
(1985)
5.90.2
5536
Seep A
(2000)
5.90.3
45641
Seep B
(2000)
6.10.2
37284
(mg/L as CaCO3)
Ca (mg/L)
680113
74427
726129
Mg (mg/L)
Fe (mg/L)
Zn (mg/L)
Cd (mg/L)
Pb (mg/L)
1476
40312
4710
0.010.01
0.020.03
1452
15611
110.5
0.060.01
0.290.04
144187
17034
102.3
0.060.01
0.250.01
Water Sampling Locations
Mine water discharge sampling
Surface water sampling
Seep A
West
Marsh
Runoff
Site 1
Site 2
Seep B
Site 4
Site 3
Mean pH
8
7
West Marsh
6
pH
5
4
Runoff
SEEP A
SEEP B
S1
3
S2
2
S3
S4
1
0
Alkalinity (mg/L as CaCO3)
Concentration (mg/L as CaCO3)
600
500
400
300
200
West Marsh
Runoff
SEEP A
SEEP B
S1
S2
S3
100
0
S4
Oxidation Reduction Potential
200
150
West Marsh
Redox (mV)
Runoff
100
SEEP A
SEEP B
50
S1
S2
S3
0
-50
S4
Calcium (Ca) concentrations (mg/L).
900
Concentration (mg/L)
800
700
600
500
400
300
200
100
0
West Marsh
Runoff
Seep A
Seep B
S1
S2
S3
S4
Magnesium (Mg) Concentrations (mg/L)
180
Concentration (mg/L)
160
140
120
100
80
60
West Marsh
Runoff
Seep A
Seep B
S1
S2
S3
40
20
0
S4
Iron (Fe) Concentrations (mg/L)
Concentration (mg/L)
160
140
120
100
80
60
40
20
0
West Marsh
Runoff
Seep A
Seep B
S1
S2
S3
S4
Zinc (Zn) Concentrations (mg/L)
14
Concentration (mg/L)
12
West Marsh
10
Runoff
Seep A
8
6
Seep B
S1
S2
4
2
0
S3
S4
Sulfate Concentrations (mg/L)
Concentration (mg/L)
2500
2000
West Marsh
Runoff
1500
Seep A
Seep B
S1
1000
S2
S3
500
0
S4
Summary
 Changes in historical concentrations
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Fe, Zn, Pb?, Cd?
 Conservative constituents do not
change
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Ca, Mg
 Concentrations change with flow
through wetland
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natural biogeochemical processes
dilution
% Change in Concentrations
Fe
12
48
23
14
34
8
Zn
60
25
10
Ca
43
2
11
Mg
41
2
14
42
28
25
SO4
-2
Conclusions
 Mine discharge waters are elevated in
metals but are net alkaline
 Metal concentrations decrease with flow
through wetland
 Wetland does not effectively treat the
discharge to acceptable quality
 Redesigning system may result in
improved effluent water quality
Acknowledgements
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Dr. Robert Nairn
Dr. Keith Strevett
Erin Breetzke
Todd Wolfard
Lisa Hare
Jacob Manko
Sharon & Janna
Robbins
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Rebecca Jim
Carrie Evenson
NSF
EBEL and BEESL
 And the REU 2000 WILD
AND WONDERFUL
WETLAND WOMEN !!!!