Mine Water Quality Changes in at the Mayer Ranch Wetland Kim Wahnee Dr. Robert Nairn Dr. Keith...

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Mine Water Quality Changes in at the Mayer Ranch

Wetland

Kim Wahnee

Dr. Robert Nairn

Dr. Keith Strevett

REU 2000

Presentation Overview

General backgroundIntroduction to study site Research questionsField and analytical methodsResultsConclusions

Tri-State Mining DistrictExtensive underground lead and zinc mining (1900-

1960s)Mine flooding began after cessation of mining and

associated dewateringPolluted artesian discharges emerged in late 197940 square mile site received Superfund status in 1983

OTTAWA COUNTY

OKLAHOMA

Picher Mining Field of the Tri-State Mining District

Mayer Ranch

Location of first major mine water discharges; November 1979 in horse pasture

At least two major seeps identifiedMine water characterized by USGS

(1985)Extensive volunteer cattail marsh

established in last 20 years

Mayer Ranch Wetland

WestMarsh

Seep A

Seep B

Meyer Ranch Wetland

Runoff

Mine drainage marsh

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?

MethodsSampled mine water discharges and surface

waters at 8 locationsIn situ measurements

pH, temperature, alkalinity, dissolved oxygen, oxidation-reduction potential, conductivity, turbidity, flow rate

Metals and anion data Ca, Mg, Zn, Fe, Cd, Pb SO4

-2, Cl-, F-, NO2-, NO3

-, PO4-3

Comparison to Historical Data

USGS(1985)

Seep A(2000)

Seep B(2000)

pH 5.90.2 5.90.3 6.10.2

Alkalinity(mg/L as CaCO3)

5536 45641 37284

Ca (mg/L) 680113 74427 726129

Mg (mg/L) 1476 1452 144187

Fe (mg/L) 40312 15611 17034

Zn (mg/L) 4710 110.5 102.3

Cd (mg/L) 0.010.01 0.060.01 0.060.01

Pb (mg/L) 0.020.03 0.290.04 0.250.01

WestMarsh

Seep A

Seep B

Site 1

Site 2

Site 3

Water Sampling Locations

Runoff

Site 4

Surface water sampling

Mine water discharge sampling

Mean pH

0

1

2

3

4

5

6

7

8

pH

West Marsh

Runoff

SEEP A

SEEP B

S1

S2

S3

S4

Alkalinity (mg/L as CaCO3)

0

100

200

300

400

500

600

Con

cent

ratio

n (m

g/L

as C

aCO

3)

West Marsh

Runoff

SEEP A

SEEP B

S1

S2

S3

S4

Oxidation Reduction Potential

-50

0

50

100

150

200

Red

ox (m

V)

West Marsh

Runoff

SEEP A

SEEP B

S1

S2

S3

S4

Calcium (Ca) concentrations (mg/L).

0

100

200

300

400

500

600

700

800

900

Conc

entra

tion

(mg/

L)

West Marsh

Runoff

Seep A

Seep B

S1

S2

S3

S4

Magnesium (Mg) Concentrations (mg/L)

0

20

40

60

80

100

120

140

160

180

Conc

entra

tion

(mg/

L)

West Marsh

Runoff

Seep A

Seep B

S1

S2

S3

S4

Iron (Fe) Concentrations (mg/L)

0

20

40

60

80

100

120

140

160

Con

cent

ratio

n (m

g/L)

West Marsh

Runoff

Seep A

Seep B

S1

S2

S3

S4

Zinc (Zn) Concentrations (mg/L)

0

2

4

6

8

10

12

14

Con

cent

ratio

n (m

g/L)

West Marsh

Runoff

Seep A

Seep B

S1

S2

S3

S4

Sulfate Concentrations (mg/L)

0

500

1000

1500

2000

2500

Conc

entra

tion

(mg/

L)

West Marsh

Runoff

Seep A

Seep B

S1

S2

S3

S4

SummaryChanges in historical concentrations

Fe, Zn, Pb?, Cd?

Conservative constituents do not change Ca, Mg

Concentrations change with flow through wetland natural biogeochemical processes dilution

% Change in Concentrations

1 2 2 3 3 4

Fe 48 14 8

Zn 60 25 10

Ca 43 2 11

Mg 41 2 14

SO4-2 42 28 25

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

Dr. Robert NairnDr. Keith StrevettErin BreetzkeTodd WolfardLisa HareJacob MankoSharon & Janna

Robbins

Rebecca JimCarrie EvensonNSFEBEL and BEESL And the REU 2000 WILD

AND WONDERFUL WETLAND WOMEN !!!!