Trends in Bioaccumulation of Fly Ash Contaminants by Aquatic

Invertebrates Downstream of the Tennessee Valley Authority Kingston

Fossil Plant

John G. Smith, ORNLand

Tyler F. Baker, TVA

Study Objectives

Assess spatial and temporal trends in the bioaccumulation of potential fly ash contaminants by aquatic invertebratesdownstream of the Kingston Fossil Fuel Plant fly ash spill.

Pleurocera canaliculatum (Silty hornsnail)

Grazer/herbivore-detritivore

Hexagenia bilineata(Borrowing mayfly)

Filter-feeder/deposit-feeder/detritivore

Target Species

Nymphs

Adults

Sampling Locations

Field Procedures

Snail “noodling”

Snails

Mayfly nymphs

Mayfly nymph

Field Procedures

Mayfly mating swarm

Mayflyadults

Snails

Laboratory Processing

Tissue extraction

Depuration?NoYes

Freeze/store at -20 C

Clean snails72 hr

Laboratory Processing

12 hr

36 hr

Freeze/store at -20 C

Mayfly nymphs

Depuration?

Rinse thoroughly with distilled water

Yes (48 hr)

No

Non-depurated

Depurated

Laboratory Processing

Freeze/store at -20 C

Mayfly adults

Sex and stage

Samples arefreeze-dried

Analyzed for suite of 26 elements with EPA 6020

Laboratory Processing

1”ND” = not depurated; “D” = depurated.2Mayfly nymphs and adults = Hexagenia bilineata; snails = Pleurocera canaliculatum.3ERM = Emory River mile; CRM = Clinch River mile; TRM = Tennessee River mile; LERM = Little Emory River mile.

Samples – 2009 & 2010Mayfly nymphs1,2

Mayfly adults2

Snails1,2

Subimagos Imagos

River/Site3 Year D ND Female Male Female Male D ND

Emory River

ERM 0.62009 - - - - - - - -

2010 - - X X - X - -

ERM 1.02009 X X - - - X X -

2010 X X X X - X X X

ERM 22009 - X - - - X X -

2010 X X X X X X X X

ERM 2.82009 - - - - - - - -

2010 - - - - X X - -

ERM 4.02009 - - - - - X - -

2010 X X - - - - X X

ERM 6.02009 - X - - - - X -

2010 X X - - - - X X

Clinch River

CRM 1.52009 X X - - X X X -

2010 X X - - X X X X

CRM 3.52009 - - - - - X - -

2010 X X X - X X X X

CRM 6.02009 - X X X - - X -

2010 X X - - - X X X

Tennessee River

TRM 560.82009 - - - - - - - -

2010 - X - - - - - -

TRM 563.02009 - - - - - X - -

2010 - - X X - X - -

TRM 567.02009 - - X X X X - -

2010 X X X X - X X -

TRM 572.52009 - - - - - - - -

2010 X X X X - X X -

Little Emory River

LERM 1.02009 - X - - X X - -

2010 - X - - - - X -

Principal Components Analysis – Snails2009 & 2010

Axis 1A

xis

2

Depurated - 2009Depurated - 2010Non-Depurated - 2010

E6.0

E6.0

E6.0

C6.0

C6.0C6.0

E2.5

E2.5

T572

C1.5

C1.5

C1.5

C3.5

C3.5

E1.0

E1.0

E4.0

E1.0

T566.3

L1.0E2.5

Axis 1

Axi

s 2

20092010

E6.0

E6.0

C6.0

C6.0

E2.5E2.5

T572

C1.5

C1.5

C3.5

E1.0

E1.0

E4.0 T566.3

L1.0

Principal Components AnalysisDepurated Snails Only – 2009 & 2010*

*(Blue and red lines join Emory River and Clinch River sites, respectively, between years)

Axis 1

Axi

s 2

Depurated - 2009Non-Depurated - 2009Depurated - 2010Non-Depurated - 2010

E6.0

E6.0

E6.0

C6.0

C6.0

C6.0

E2.5

E2.5

T572

C1.5

C1.5

C1.5

C3.5

C3.5

E1.0

E1.0

E4.0

E1.0

T566.3

L1.0

E2.5

E1.0

E4.0

T572

L1.0

T566.3

T560.8

C1.5

Principal Components Analysis – Mayfly Nymphs2009 & 2010

Principal Components Analysis – Adult Mayflies2009 & 2010

Principal Components Analysis – Adult MayfliesExcluding Ca, Fe, Mg, Mn, K, Na - 2009 & 2010

Concentrations of As, Se, and Hg – Snails2009 & 2010

Mercury

Site / River mile

Hg

(g/g

dry

wgt)

0.0

0.1

0.2

0.3

0.4

ERM CRMTRM

LERM

Selenium

Se ( g

/g d

ry w

gt)

0

5

10

Arsenic

As (

g/g

dry

wgt)

0

5

10

15

20

25

2009 (Depurated)2010 (Not depurated)2010 (Depurated)

Kingston FossilFuel Plant

Emory Riverconfluence

Clinch Riverconfluence

Proposed EPA whole body fish criterion

EPA methylmercury fish tissue criterion

Concentrations of As, Se, and Hg – Mayflies2009 & 2010

Mercury

Site / River mile

Hg

(g

/g d

ry w

gt)

0.00

0.25

0.50

0.75

1.00

1.25

ERM CRMTRM

LERM

Selenium

Se

(g

/g d

ry w

gt)

0

4

8

12

Arsenic

As

(g

/g d

ry w

gt)

0

5

10

15

20

25

30

35

40

45

50

55

2009 (Not depurated)2010 (Not depurated)2009 (Depurated)2010 (Depurated)

Kingston FossilFuel Plant

Emory Riverconfluence

Clinch Riverconfluence

Proposed EPA whole body fish criterion

EPA methylmercury fish tissue criterion

Mercury

Site / River mile

Hg

(g/g

dry

wgt)

0.0

0.1

0.2

0.3

0.4

ERM CRMTRM

Selenium

Se

(g/g

dry

wgt)

0

5

10

Arsenic

As

(g/g

dry

wgt)

0.00

0.25

0.50

0.75

Male Subimagos (2009) Female Subimagos (2009)Male Subimagos (2010)Female Subimagos (2010)

Kingston FossilFuel Plant

Emory Riverconfluence

Clinch Riverconfluence

Proposed EPA whole body fish criterion

EPA methylmercury fish tissue criterion

ND

Mercury

Site / River mile

Hg

(g

/g d

ry w

gt)

0.0

0.1

0.2

0.3

0.4

ERM CRMTRM

LERM

Selenium

Se

(g

/g d

ry w

gt)

0

5

10

Arsenic

As

(g

/g d

ry w

gt)

0.00

0.25

0.50

0.75

Male Imagos (2009)Female Imagos (2009)Male Imagos (2010)Female Imagos (2010)

Kingston FossilFuel Plant

Emory Riverconfluence

Clinch Riverconfluence

Proposed EPA whole body fish criterion

EPA methylmercury fish tissue criterion

Nymphs Subimagos Imagos

Conclusions - General

Highest concentrations of elements for all groups generally in Emory and Clinch Rivers downstream of the spill site

Highest concentrations of many elements in mayfly nymphs typically at ERM 1.0

Highest concentrations of many elements in adults typically adjacent to the spill site (i.e., around ERM 2.0)

Highest concentrations of many elements in snails generally at Clinch River sites (CRM 1.5 and CRM 6.0)

Conclusions - General

Spatial trends were generally stronger than temporal trends, and they appeared to be similar between years

Depuration had a significant effect on concentrations of most elements (e.g., Cd, Cu, and Zn were higher in both species)

Bioaccumulation of some elements is clearly different in male and female mayflies

Differences between male imagos and subimagos appear to be related mostly to differences in concentrations of essential elements

Conclusions – Arsenic

Depurated versus non-depurated snails suggest As may be bioaccumulating in tissue

Highest concentrations generally found in mayfly nymphs

Depurated versus non-depurated mayfly nymphs suggest less tissue bioaccumulation than in snails

Amount of As leaving the water via adult mayflies is minimal(but does this apply to all insects?)

Primary source of As appears to be KIF fly ash, but there may be secondary source in Clinch River

Conclusions – Selenium

Depuration had minimal effect on concentrations in snails and nymphs

Concentrations highest in mayfly nymphs and lowest in snails

Primary source of Se appears to be KIF fly ash

Concentrations declined downstream of ERM 1.0 in nymphs, and downstream of ERM 2 in the adults

Concentrations in snails appeared to increase with distance downstream from ERM 2.5 to CRM 1.5

Concentrations generally only slightly lower in adult mayflies than the nymphs

Conclusions – Mercury

Only contaminant that showed similar spatial trends among all three groups

All three groups indicated that the primary source of Hg is the Clinch River upstream of CRM 6.0

Depuration had little effects on concentrations of Hg in snails

Depuration drastically reduced concentrations in nymphs from Clinch River sites, but not the Emory River sites

Concentrations in adult mayflies were considerably lower than in the nymphs

Questions

How much are native soils contributing to element concentrations?

What factors are contributing to differences between snails and mayfly nymphs? (physiological, environmental)

What effects do natural differences in water quality of the three rivers have on availability, transport and fate of contaminants?