lead contamination in the big river due to historical...
TRANSCRIPT
Lead Contamination in the Big River
due to Historical Mining Activities
-Channel Sediment
-Floodplain Soils
-Focus on Jefferson County
Bob Pavlowsky Department of Geography, Geology, and Planning
Ozarks Environmental and Water Resources Institute
Missouri State University
Big River Watershed (2,400 km2)
Historical Land UseCrops, Population, & Livestock
0
20
40
60
80
100
120
140
1840 1860 1880 1900 1920 1940 1960 1980 2000
Po
pu
lati
on
De
nsi
ty (
Pe
rso
ns/
km2
)
Jefferson County
St. Francois County
Washington County
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
1840 1860 1880 1900 1920 1940 1960 1980 2000
Co
un
t
Dairy Cattle
Other Cattle
Hogs
Livestock
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1840 1860 1880 1900 1920 1940 1960 1980 2000
Ton
s P
rod
uce
d
Bu
she
ls P
rod
uce
d
Wheat (Bushels) Corn (Bushels) Dry Hay (Tons)
Peak land use disturbance
1880 to 1920
Large-scale mining from 1900 to 1972; peak in 1942National Mill
(1924)
Bonne Terre
Chat Pile
Leadwood
1937
Big River
Tailings Piles: Ca and Pb Size FractionationChat: fine gravel Tailings: sand Slimes: ultra-fines
21-25% Ca= Dolomite host rock High Pb in all sizes
Desloge Pile in 2010: Stabilized and Contained
Problem: Mining Sediment in the Big River
• Mine waste inputs to the natural river system
– Chat and Tailings deposited in channel and on floodplain
– Reworking by erosion and weathering (long-term effects???)
• 3 types of sediment concern (size and mill process)
– Chat- 4 to 16 mm or “fine gravel”
• Dry separation (gravity methods)
– Tailings- 0.06 to 0.2 mm or “fine sand”
• Wet separation (Shaking tables or flotation)
– Slimes- <32 um or “fine silt”
• Powdered rock
• Too fine for separation or efficient recovery
Concerns over soil
contamination due to
mining and other
industrial sources
Residential soil
problems in Jefferson
County
Red dots show
concentrations over
1,200 ppm Pb.
MC Barnhart
MC Barnhart
MC Barnhart
Leptodea leptodon (scaleshell) Lampsilis abrupta (pink mucket)
Cumberlandia monodon (spectaclecase)
Endangered Mussels are
threatened by:
1) Sediment-Pb toxicity
2) Channel instability
3) Sedimentation
Washington County Lead District
OBJECTIVES
1) What are Pb concentrations within historical
channel and floodplain deposits?
2) What is the longitudinal distribution of storage? How
much is still in the river?
3) What will happen in the future? Contamination or
Recovery?
Management plans (control and clean-up measures)
Valley Cross-section
What did we do?
171
172
173
174
175
176
177
178
179
0102030405060
Ele
vati
on
(m
)
Distance across channel looking downstream (m)
Site 6 - T8
172
172.5
173
173.5
174
174.5
175
0 100 200 300 400 500 600
Ele
vati
on
(m
)
Distance (m)
Longitudinal Profile - Site 6
T2 T3 T4 T5 T6 T7 T9T8T1
Sinuosity = 1.15Pool Slope = .003
Longitudinal Survey
Cross Section Survey
Blackwell At CC Bridge (R-km 115)
Blue- channel bottom and banks
Red- probe depth transect
Green-maximum probe depth
GlideGlide
Channel Sample units
High Bar Glide
Big River above Flat River at hwy 67
Thickness of Bed and Bar DepositsTile Probe Refusal
Floodplain Sampling
Floodplain Cut-banks
High FP above Flat-6m Low FP at Cherokee Landing-4m
---contact---
---contact---
0
500
1,000
1,500
2,000
2,500
0 25 50 75 100 125 150 175 200
Pb
pp
m
River Kilometer above the Meramec River
FWS 07 riffle slackwater
bulk
FWS 08 riffle slackwater bulk
MSU 09 bar <2mm
MSU 09 glide <2mm
MSU 09 Geo-mean
Probable Effect
128 ppm Pb
Big River Channel sed-PbContamination
171- Eaton Ck155- Flat R Ck116- Mill Ck
99- Min Fork34- Belews Ck
CHANNEL RESULTS
Selective transport of finer sediment Longitudinal size sorting of mining sediment occurs over channel distances of +/- 30 km
0
2
4
6
8
10
12
14
16
18
20
0 25 50 75 100 125 150 175 200
Ca
%
River Kilometer
B- Percent Calcium
<250 mm
1-2 mm
4-8 mm
“Pure” dolomite = 21.7% Ca & calcite = 40.1% Ca
Fines Sand Chat
um
Fine gravel or CHAT grain counting
Chat Grain Counts
0
20
40
60
80
100
0 25 50 75 100 125 150 175 200
Pe
rce
nt
of
Tota
l G
rain
s
River Kilometer
Chat Grain Counts (4-8 mm fraction)
Chips Trend
Natural Trend
Chips-Trib
Natural-Trib
Flat R Ck
Natural (chert/feldspars)=
200-600 ppm Pb
Dolomite Chips=
800-5,400 ppm Pb
Contrasting size-Pb relationship between
proximal and distal channel segments(last mine drains to the Big River at R-km 135)
0
1000
2000
3000
4000
5000
6000
0 25 50 75 100 125 150 175 200
Pb
pp
m
River Kilometer
E- ppm Lead
<250 mm
1-2 mm
4-8 mm Fines
Fines
um
Unit Channel Storage (sand and fine gravel)m3/100 m
Big River above Mineral Fork: 2,566 +/- 25% (2s) m3/100 m
--TRIBUTARIES--
up---------- MAINSTEM ----------------------------------------------- down
D
D
D
bD
b
D = us of dam
b = thalweg breach
Contaminated
---Old Topsoil contact---
Uncontaminated
FLOODPLAIN RESULTS
Washington State Park Valley Transect
Washington State park valley Transect
162
164
166
168
170
172
174
176
0 50 100 150 200 250 300
Ele
vati
on
(m
ab
ove
msl
)
Valley Distance (m)
>400 ppm Pb
Max Pb
Gravel
Refusal
Surface
0
5,000
10,000
15,000
1 2 3 4 5 6 7 8
Pb
(p
pm
)
Core #
Surface Pb
Max Pb
Morse Mill Park on the Big RiverPb profiles at R-km 50
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
0 50 100 150 200 250 300 350 400 450 500 550
Ele
vati
on
(m
)
Distance (m)
Core 8 Core 9 Core 10
Core 15 Core 14
Core 13
Core 16
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000
Dep
th (
cm)
Pb (ppm)
T-2 Core 8 - Morse Mill
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000
Dep
th (
cm)
Pb (ppm)
T-2 Core 9 - Morse Mill
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000
Dep
th (
cm)
Pb (ppm)
T-2 Core 10 - Morse Mill
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000D
epth
(cm
)Pb (ppm)
T-2 Core 15 - Morse Mill
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000
Dep
th (
cm)
Pb (ppm)
T-2 Core 14 - Morse Mill
0
50
100
150
200
250
300
350
400
0 2,000 4,000 6,000
Dep
th (
cm)
Pb (ppm)
T-2 Core 13 - Morse Mill
0
50
100
150
200
250
300
350
400
0 100 200 300 400 500
Dep
th (
cm)
Pb (ppm)
T-2 Core 16 - Morse Mill
High Pb concentrations extend far downstream
Mining Area
St. Francois Co.
R-km 171 to 135
Recent FP surface deposits decrease in Pb
Concentration below mining areas
0
500
1,000
1,500
2,000
2,500
3,000
0.0 5.0 10.0 15.0 20.0 25.0
Pb
Con
cen
trati
on
(p
pm
)
River km above Meramec River (0=mouth, 24.2= Byrnesville Gage)
Lower Big River Sediment Contamination
Bank Sample
Bar Sample
Bed Sample
Terrestrial PEC =400 ppm
Aquatic PEC =128 ppm
Floodplain Storage PotentialAreas in km2 by county
(Source: USDS Soil Survey and aerial photographs)
Haymond / Wilbur Kaintuck
Jefferson Co. (Lower) St. Francois Co. (middle)
Total Segment
Storage
Unit Channel
Storage
decreases
downstream
Unit floodplain storage increases downstream
Total by segment
Storage by unit length
St. Francois Co. (middle) Jefferson Co. (Lower)
1) Total Pb Storage
in Alluvial Deposits
= 230,000 Mg
2) St. Francois Co.
Floodplain 26.7%
(Channel 1.1% )
3) Jefferson Co.
Floodplain 71.6%
(Channel 0.6% )
4) About 1/3 of
tailings Pb
remaining in the
District is stored in
alluvial deposits of
the Big River.
Lower Big River
•Over the past 70 years, the
lower Big River has been
relatively stable, but disturbance
reaches represent ~32% of study
reach
R-km
Bank Erosion is a source of present day Pb contamination
Floodplain Mapping Using USDA Soil Series
Contaminated Deposits
Highest Pb Concentrations
Gold bars show higher
elevation terrace deposits that
are not contaminated.
Moderate & thin
Moderate &
thick
Screening-level
Indicator of
Floodplain Soil Risk
USDA-NRCS
Soil Survey
Floodplain Contamination
•Terrestrial Contamination
>400 ppm
Conclusions
Location Sediment Volume (%)
County In-Channel Floodplain
St. Francois 1.5% 19.7%
Jefferson 2.6% 76.2%
Total Sediment Volume = 90,461,000 m3
Location Pb Mass (%)
County In-Channel Floodplain
St. Francois 1.1% 26.7%
Jefferson 0.6% 71.6%
Total Pb Mass = 230,000 Mg
1) Channel Pb metal mass
Almost 2x more stored in
channel segments in St.
Francois Co (higher Pb
conc.)
2) Historical Floodplain
Storage Largest sink by
far at >95%. Over 70% in
Jefferson Co. due to
thicker deposits, higher
concentrations, and larger
FP areas.