Current Liabilities and Payroll Chapter 11 HORNGREN ♦ HARRISON ♦ BAMBER ♦ BEST ♦ FRASER ♦ WILLETT.
Biogeochemical Cycling of Selenium and Mercury in Bighorn ... · ♦Elevated Hg levels in fish...
Transcript of Biogeochemical Cycling of Selenium and Mercury in Bighorn ... · ♦Elevated Hg levels in fish...
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Biogeochemical Cycling of Selenium and Mercury in Bighorn Lake, Bighorn Canyon National Recreation Area, MT and WY
Funding provided by: US Geological Survey and National Park Service
D. Naftz and E. Barnhart, USGS, Helena, MT; D. Krabbenhoft and S. Janssen, USGS,Middleton, WI; C. Eagles-Smith, USGS, Corvallis, OR; C. Stricker, USGS, Lakewood, CO;T. Schmidt, USGS, Ft. Collins, CO; M. Ruggles, MT FWP, Billings, MT
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♦ Elevated Hg levels in fish tissue relative to other National Parks
♦ Potential for geogenic sources of Hg (Yellowstone National Park)
♦ Sediment mitigation actions possible in future
♦ Selenium inputs to reservoir via WY landscapes
♦ Evolving information on Hg cycling in western reservoirs
♦ New EPA chronic selenium criteria approved in late 2016
PROBLEM
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♦ Limnological and riverine controls on [Hg] and [Se]♦Hg and Hgisotopes in fish tissue♦Microbial community dynamics and Hg methylation♦Se and C / N isotopes in fish tissue♦Se sources to Bighorn Lake♦Comparison to other reservoirs♦Next steps
OUTLINE
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BACKGROUNDHg methylation
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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BACKGROUNDBighorn Lake Hg advisories
USEPA – 0.3 mg/kg (ww)FDA – 1.0 mg/kg (ww) – “do not eat”
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BACKGROUNDNew EPA 2016 Selenium Criteria
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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BACKGROUNDWY selenium issues
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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LIMNOLOGYSalinity gradients
♦ 2015 freshet replaced by higher salinity plume
♦ 2016 has higher salinity
♦ Freshwater lens below higher salinity layer
Early July Late August
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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LIMNOLOGYDissolved O2 gradients
♦ 2015 no inverted density gradient
♦ 2016 inverted density gradient associated with low DO areas
♦ Settling POMaccumulating on top of lower density freshwater lense
Early July Late August
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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LIMNOLOGYpH gradients
♦ Low pH values in 2015 likely degradation of POM on higher salinity layer (40 m)
♦ Low pH values during 2016 support areas of POMdegradation
Early July Late August
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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LIMNOLOGYDO gradients in side canyons
♦ Restricted circulationin side canyons
♦ Elevated levels ofMeHg in side canyonsediment
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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2015 2016
0.1
0.4
1.8
7.7
32.5
138.0
Turb., in NTU
0.1
0.4
1.8
7.7
32.5
138.0
Turb., in NTU
LIMNOLOGYTurbidity and THgsuspended
DISTANCE FROM YELLOWTAIL DAM, IN KM
Early July Late August
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
♦ Higher THgsuspendedduring July synoptic
♦ Turbidity and THgsuspendedgenerally agree during both synoptics
♦ Delivery of elevated THgsuspended to forebay
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400 500 600 700 800 900
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
SPECIFIC CONDUCTANCE, IN µS/CM
DIS
SO
LVE
D S
ELE
NIU
M, I
N µ
G/L
AfterbaySide channelUpper reservoir
LIMNOLOGYSC and Se gradients
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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♦ Increasing Hg with increasing length (common)
♦ Numerous samples exceed FDA “do not eat” advisory
♦ Anomalous fish concentrations in upper reservoir sites?
♦ Tailwater fishery shows lowest mercury concentrations
MERCURY IN FISH TISSUE
Upper reservoir anomaly
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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♦ 199Hg = 199Hg(permil) / 198Hg(permil)
♦ Low 199Hg in tailwaterfishery reflects less photochemical processing of the Hg
♦ Water released from Yellowtail dam (> 50 m in depth) less opportunity for photochemical processing
199Hg IN FISH TISSUE
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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SRBs in Sediment SamplesDO gradients in side canyons
♦ Known Hg Methylators
♦ Elevated levels of MeHg in side canyon sediment
0
5000
10000
15000
20000
25000
1 2 5 8 10 13 15
15_r
eplic
ate 18 19
dsrB
cop
ies /
0.5
g s
edim
ent
Sulfate Reducing Bacteria
1000000
10000000
100000000
1E+09
11_
repl
icat
e 2 5 8 10 13 15 18 19
Bact
eria
l cop
ies /
0.5
g so
il
Total Bactera in Sediment
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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SRBs in Water SamplesDO gradients in side canyons
♦ Known Hg Methylators
♦ Elevated levels of MeHg in side canyon sediment
1
10
100
1000
10000
1 2M
2 11
3M 2 2M
5 20
M5
60M
5 2M
8 60
M8
2M10
50M
10 2
M13
12M
15A
2M18
32M
18 2
M19
51M
19 2
M
Bact
eria
l cop
ies /
mL
of w
ater
Total Bacteria in Water
0
5
10
15
20
25
30
35
1 2M
2 11
3M 2 2M
5 20
M5
60M
5 2M
8 60
M8
2M10
50M
10 2
M13
12M
15A
2M18
32M
18 2
M19
51M
19 2
M
dsrB
cop
ies /
mL
of w
ater
Sulfate Reducing Bacteria
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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• All sediment sites amplified
• Only 18B from the water samples amplified
-con 13 19 18 15 10 8 5 2 1
-con 13T 2B 8B 1B 5M 5B 15A 13 8T 5T 10B 5M
-con 18BR 18T 5M 15T 1T 19T 19B 18T 18B 10T 2T
Newly Identified Mercury Methylation GenesSediment Water Samples
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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FISH TISSUE SELENIUMTailwater fishery is anomalous
♦ Higher [Se] at depth in reservoir is reflected in tailwater fishery
♦ Some tissue samples in tailwater exceed/approach 2016 EPA chronic criteria of 11.3 mg/kg (dw)
♦ High Kds in dam release may influence Se uptake in lower trophic levels and smaller fish in tailwater?
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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FISH TISSUE C and N ISOTOPESYou are what you eat
♦ Tailwater brown trout are a full trophic level lower than reservoir population
♦ Is the tailwater food web influenced by organic detritus released from the reservoir chemocline?
♦ Is the high insect biomass in the tailwater influenced by selenium- and organic-rich detritus from the reservoir?
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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Se INPUTSBighorn vs. Shoshone Rivers
~ 3,420 kg Se/yr
~ 783 kg Se/yr
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
Oct Jan Apr Jul Oct Jan Apr Jul100
1,000
10,000
WY 2015 WY 2016
ME
AN
DA
ILY
DIS
CH
AR
GE
, IN
FT3 /S
EC
Lentic Se standard
Bighorn River at Kane, WY
Oct Jan Apr Jul Oct Jan Apr Jul0
0
0
WY 2015 WY 2016
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
DIS
SO
LVE
D S
ELE
NIU
M C
ON
CE
N-
TRA
TIO
N, I
N µ
G/L
Lentic Se standard
Shoshone River nr Lovell, WY
Bighorn River Shoshone River
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Se INPUTSAreas susceptible to Se contamination
300 2
l., ate r
ileeSBighorn Lake
“Areas susceptible to irrigation-induced Se contamination of water and biota”
“Area where some bird eggs contain embryotoxicconcentrations of selenium”
“Area or site where surface water is selenium contaminated”
MTWY
0 50 km
Bighorn Rivergage
Shoshone River gage
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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Lake Koocanusa(Elk River only)
Bighorn Lake(Bighorn River only)
Se INPUTSComparison to Lake Koocanusa
♦ Lake Koocanusa volume = 7 km3
♦ Bighorn Lake volume = 1.7 km3
♦ Elk River = High Se and minor flow contributor
♦ Bighorn River = High Se and major flow contributor
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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N = 87 N = 50
0
2,000
4,000
6,000
8,000
10,000
12,000
ME
AN
AN
NU
AL
DIS
CH
AR
GE
, IN
CFS
0
2,000
4,000
6,000
8,000
10,000
12,000
ME
AN
AN
NU
AL
DIS
CH
AR
GE
, IN
CFS
N = 22 N = 21
0.37 INFLOW RATIOSLake Koocanusa and Bighorn Lake
Elk:Kootenay Bighorn: Shoshone2.42
Elk / Kootenay Bighorn / Shoshone
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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0.0
0.5
1.0
1.5
Bighorn Lake2015-16
Lake Koocanusa2015-16
N = 33
N = 56
2.0
G/L
µ N I,e
SD
EVL
OS
SID
INDIVIDUAL SAMPLES
Se IN WATERComparison to Lake Koocanusa
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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0
5
10
15
20
25
Se IN FISH TISSUEComparison to Lake Koocanusa
Lake Koocanusa (MT FWP) Bighorn Lake and tailwater (USGS / MT FWP)
Saug
er--
Rese
rvoi
r
rain
bow
trou
t --R
eser
voir
brow
n tr
out -
-Res
ervo
ir
Wal
leye
--Re
serv
oir
)YLE
ON
LCS
UM(
DWPP
M
, I
NeS
HISF
SPECIES
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
brow
n tr
out -
-Tai
lwat
er
rain
bow
trou
t --T
ailw
ater
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LAKE POWELL COMPARISONSimilar reservoir morphology
Bighorn Lake, MT/WY
Lake Powell, AZ/UT
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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DISTANCE FROM YELLOWTAIL DAM, IN KM DISTANCE FROM GLEN CANYON DAM, IN KM
SIDE CANYON ANOXIABighorn Lake DO/Hg Lake Powell DO Lake Powell MeHg
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LAKE KOOCANUSA BIGHORN LAKE♦ Se sourced from British
Columbia
♦ Two major river inflows (high Se + low flow)
♦ Modeled Se loads up to 13,000 kg/yr
♦ [Se] in reservoir ranges from 0.7 to 1.2 µg/L
♦ Listed under Section 303 (d) as threatened by Se
♦ Se sourced from Wyoming
♦ Two major river inflows (hiselenium + high flow)
Estimated Se loads ~ 4,20kg/yr
[Se] in reservoir ranges fro0.25 to 1.9 µg/L
No 303 (d) listing for Se
Tailwater impacts?
gh
♦ 0
♦ m
♦♦
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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LAKE POWELL BIGHORN LAKE♦ Long, narrow reservoir with
numerous side canyons
♦ Low levels of Hgwater in main channel
♦ Seasonal anoxia in narrow side canyons
♦ Elevated levels of MeHgwater in side canyons
♦ Hg fish advisory for lower reservoir
♦ Long, narrow reservoir with some side canyons
♦ Low levels of Hgwater in main channel
♦ Seasonal anoxia in side canyons
♦ Higher proportion of MeHgsediment and SRBsediment in side canyons
♦ Hg fish advisory for entire reservoir
Limnology [Hg]fish [Se]fish Se sources Other reservoirs
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Se CONCEPTUAL MODEL
0.1
0.4
1.8
7.7
32.5
138.0
Turbidity
Kdand TTFs
Watershed inputs Reservoir transformations Afterbay TailwaterBighorn R.
Greybull R.
Shoshone R.Kdand TTFs
Kdand TTFsSe
sources and load reduction potential
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BIGHORN LAKE FUTURE NEEDSSPARROW model (Preston et al., 2009) for Bighorn, Greybull, and Shoshone watersheds
Ecosystem-scale model (Presser and Luoma, 2010) for Bighorn Lake
Bighorn Lake Study Team
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MANAGEMENT OPTIONSThermocline manipulation in side canyons
♦ Oxygenate bottom water and near-surface sediments
♦ Photodegrade MeHg?Solar pump operating at Newcastle Reservoir, Utah
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SUMMARY♦ Low DO in side canyons and microbial populations
support Hg methylation
♦High Hg levels in larger reservoir fish
♦Elevated Se levels in reservoir water and tailwater fish tissue
♦Se loads to BICA from Bighorn River watershed
♦Similar Hg processes in Bighorn Lake and Lake Powell
♦Se model for BICA would be useful as an adaptive management tool