PREDICTING PCB UPTAKE IN FISH

AFTER IN-SITU SEDIMENT REMEDIATION

Upal Ghosh Department of Chemical, Biochemical, & Environmental

Engineering

University of Maryland Baltimore County, Baltimore, MD

USEPA National Association of Remedial Project Managers conference Engineers Forum

Atlanta, GA

NRC STUDY ON EFFECTIVENESS OF DREDGING

PCB concentrations in water samples collected approximately 0.5 miles downstream of the dredging operations in the Grasse River. Dredging began approximately June 8, 2005 and ended October 21, 2005. Source: Connolly et al. 2006.

Of the 20 megasites evaluated by the NRC committee: (National Research • 25% achieved goals Council June 2007) • 50% did not achieve goals or were not monitored well • 25% not enough time has elapsed to form judgment

The report urges EPA to step up its monitoring activities before, during,

and after dredging efforts at all sediment megasites

MANAGING EXPOSURE FROM HISTORIC DEPOSITS

OF CONTAMINATED SEDIMENTS

• How do you clean up an ecologically sensitive site without destroying it?

• Contaminated sediment sites are large

• Current technologies are disruptive and expensive

• Need for innovative techniques that reduce risks

PCB contaminated wetland in VA 3

activ

ated c

arbon

soot

carbo

n

partic

ulate

coal

partic

ulate

charc

oal

heav

y fue

l oil

coal

tar

Pula

kerog

en

co lla

gen

humi

c acid

degra

ded a

lgae

amorp

hous

orga

nic m

a tter

oxidi

zed h

umic

acid

cutic

lealg

aelig

nin

ce llu

lose

seve

ral so

ils an

d sed

imen

t

NATURE OF SOIL/SEDIMENT PARTICLES

charcoal

• Sediment contains sand, silt, clays, charcoal, wood,coal char, coal, & shells

char • PCBs/PAHs bound to carbonaceous particles less bioavailable 7

wood 6

5sand 4

3shell 2

1

0

Phenanthrene partitioning for various organic materials

log

(K oc

)

Petrography images

From: Ghosh et al. Environ. Sci. Technol. 2003 coal charcoal coke 4

PCB ABSORPTION EFFICIENCY IN A CLAM

From: McLeod et al. Environ. Sci. Technol. 2004

PCB ABSORPTION EFFICIENCY IN WORMS PCB spiked to sediment or PCB spiked to AC and added to sediment 93% less uptake when PCBs associated with AC

-Side view of a lab microcosm 2 days after placing a layer of AC on sediment -AC is slowly worked into the sediment through bioturbation

Sun & Ghosh, ES&T 2007

PCB

in w

orm

(ug/

g w

et w

t.)

0.3

0.2

0.1

0.0

PCB in sediment

PCB in AC

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona

PCB homolog

Beckingham et al. Environ. Sci. Technol. 2011

6

90

% re

duct

ion

in p

orew

ater

80 70 60 50 40 30 20 10

SUMMARY RESULTS FROM LABORATORY STUDIES

100 100

0 0

% re

duct

ion

in b

ioup

take

90 80 70 60 50 40 30 20 10

mar

ine

poly

chae

tes -

PCBs

(8,9

)

mar

ine

clam

s -P

CBs

(16)

mar

ine

amph

ipod

s -PC

Bs)

(9

mar

ine

wor

m -

PAH

s (10

)

fres

hwat

er o

ligoc

haet

es -

PCBs

(11)

fres

hwat

er cl

am -

PCBs

)

(16

terr

estr

ial w

orm

-di

oxin

san

d fu

rans

(15)

mar

ine

sedi

men

t -PC

Bs)

(12

mar

ine

sedi

men

t -PA

Hs

)(1

3fo

ur fr

eshw

ater

sedi

men

ts -

PCBs

(11)

mar

ine

sedi

men

t -D

DT

)(1

4flo

odpl

ain

soils

-di

oxin

san

d fu

rans

(15)

7

CONCEPTUAL MODEL OF TREATMENT

STRATEGY

Drinking water

Activated carbon amended to surficial sediments reduces contaminant exposure to food chain through:

1) Reduced bioaccumulation in benthic organisms

2) Reduced flux into water column and uptake in the pelagic food web.

3) In the long-term, the carbon amended layer is covered with clean sediment.

8

RECENT FEATURE ARTICLE IN ES&T: In-situ Sorbent Amendments: A New Direction in Contaminated Sediment Management

9

USE OF AMENDMENTS FOR IN-SITU REMEDIATION OF

SUPERFUND SEDIMENT SITES

OSWER Directive 9200.2-128FS; April 2013

10

RECENT DEMONSTRATION PROJECTS San Francisco Bay, Grasse River, Trondheim Harbor, Grenlandsfjords, CA, USA, 2006 NY, USA, 2006 Norway, 2006 Norway, 2009

SLURRY INJECTION AND ROTOTILLER.

SLURRY INJECTION AND COVERED ROTOTILLER

ACTIVE CAP OF SITE CLAY AND ACTIVATED CARBON

SLURRY INJECTION WITH AND WITHOUT CLAY

MIXTURE

Bailey Creek, Canal Creek, Berry’s Creek, Abraham’s Creek, VA, USA, 2009 MD, USA, 2010 NJ, USA, 2012 MD, USA, 2014

PELLETIZED CARBON

DELIVERY (SEDIMITE)

PELLETIZED CARBON

DELIVERY (SEDIMITE)

PELLETIZED CARBON WITH DEGRADERS DELIVERY (SEDIMITE)

PELLETIZED CARBON

DELIVERY (SEDIMITE)

APPLICATION IN A RIVER (Participants: Alcoa, EPA, UMBC, Stanford University, Anchor Env., Brennan, Tetra Tech, ArcadisBB&L, QEA)

•L-shaped silt screen to minimize suspended particle transport

•Equipment mobilized on barges

•Target dose of activated carbon = 2.5% in surficial sediments

•No measurable change in water-column PCBs downstream

•Post-treatment monitoring to continue for 2-3 years 12

IN-SITU ASSESSMENTS OF WATER QUALITY

13

In-river deployment of field exposure cages with L. variegatus for baseline study using a modified ASTM draft method (Burton et al. 2005)

L. variegatus

0.0

0.5

1.0

1.5

2.0

2.5

3.0

PCB IN WORMS AND WATER VS. CARBON DOSE 1,100

PCBs

in w

orm

s (m

g/kg

tiss

ue)

Background Background Background Background

Mixed Mixed Mixed Mixed

Injected Injected Injected Injected

Layered Layered Layered Layered

1-year after AC (2007)

2-years after AC (2008)

3-years after AC (2009)

63-99% reduction from background each year

A. Bioaccumulation in laboratory exposures

Before AC (2006)

Activated carbon (% dry wt.)

PCBs

in e

quili

brat

ed w

ater

(ng/

L)

B. Aqueous equilibrium 1,000 900

800

700

600

500

400

300

200 95-100% reduction from background each year 100

0 0 2 4 6 8 10 12 14 16

Activated carbon (% dry wt.)

• Reduced uptake in field plots with increasing AC dose

• > 90% reduction for all treatment sites in 2009 for AC dose >4%

• Little incremental benefit above 5%AC

• Greater reduction in aqueous PCBs compared to worms

LABORATORY EXPOSURE EXPERIMENTS

Water flow in aquaria tanks • Treatments:

• Clean sediment (Rhode River) • PCB impacted sediment (Grasse River) • PCB impacted sediment-treated with AC

• Replicate aquaria with passive samplers in water column and sediment

• Fish species: Zebrafish • PCB-free diet • Sampling after 45 and 90 days

Sediment

Passive samplers

Components in each aquaria15

POREWATER AND OVERLYING WATER PCBS IN

GRASSE RIVER SEDIMENT AFTER 90 DAYS

4.3

233.

2

283.

9

95.0

11.3

2.4

0.0

0.1

0.4

0.4

0.2

0.1

0

50

100

150

200

250

300

Mono Di Tri Tetra Penta Hexa

Pore

wat

er P

CBs (

ng/L

)

PCB homologs

Untreated Grasse River

Treated Grasse River

0.0

41.4

82.6

50.0

8.0

1.9

0.0 5

.0

1.4

0.8

0.2

0.2

0 10 20 30 40 50

60 70 80 90

Mono Di Tri Tetra Penta Hexa

Ove

rlyi

ng w

ater

PCB

s (ng

/L)

PCB homologs

Untreated Grasse River

Treated Grasse River

• Porewater PCB concentration was reduced by two orders of magnitude

• PCBs in overlying water was also greatly reduced (24-30 fold) and was close to that seen in the clean Rhode River sediment.

• In the PCB-impacted untreated sediment tanks, porewater PCB concentrations were 37 fold higher than the overlying concentrations indicating sediment as the PCB source to the water column.

16 16

PCB RESIDUE IN ZEBRAFISH AFTER 90 DAYS

0.4

6.5

13.1

3.9

1.9

1.0

0.1 0.

9 1.2

0.5

0.4

0.3

0

3

6

9

12

15

Di Tri Tetra Penta Hexa Hepta

C lip

id (µ

g/g

)

PCB homologs

Untreated Grasse River

Treated Grasse River

The total PCB concentration in fish decreased by a factor of 8 after treatment with AC.

17

PREDICTING PCB UPTAKE IN FISH

Steady-State Approach

Clipid ≈ Klipid.Caq Klipid ≈ KOW

Kinetic Approach dMB/dt = WB (k1CW,O+IR.α.CS)-k2 MB (Arnot & Gobas 2004)

No uptake through food- PCB-free diet

k1

k2 18 18

EQUILIBRIUM & KINETIC MODEL PREDICTIONS

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E-03 1.E-02 1.E-01 1.E+00 1.E+01

Pred

icte

d C

lipid

(µg/

g)

Observed C lipid (µg/g)

Untreated-45 days

Untreated- 90 days

Treated- 45 days

Treated 90 days

Equilibrium

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E-03 1.E-02 1.E-01 1.E+00 1.E+01

Pred

icte

d C

lipid

(µg/

g)

Observed C lipid (µg/g)

Untreated-45 days

Untreated90 days

Treated- 45 days

Treated- 90 days

Kinetic Model

• Fish are not reaching equilibrium in the 90 day exposure

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LOW-IMPACT AMENDMENT DELIVERY TO SEDIMENT

1. Agglomerates delivered from water surface 2. Sinks to sediment surface and resists resuspension 3. Breaks down slowly 4. Mixed into sediment by bioturbation 5. Binds contaminant and reduces uptake in the aquatic food chain 20

Sedi

Mite

™

RESTORATION & REMEDIATION OF MIRROR LAKE,

DOVER, DE

• Urban lake sediments impacted with PCBs and PAHs

• Ecological restoration will include removal of sand bar and creation of wetlands

• In-situ treatment of surface sediments with AC to reduce exposure.

• Monitoring includes PCBs in porewater, surface water, benthic invertebrates, and fish.

• In addition, ongoing inputs are being tracked.

Link to video documentary

KEY MESSAGES Amendment with AC will be most effective at:

• sites that are depositional in nature • sites less prone to sediment erosion • where native bioavailability of contaminants is high • ongoing contribution from off-site sources have been controlled.

AC amendment provides several advantages over traditional methods: • less disruption to benthic habitats in sensitive systems • amenability to shallow or constricted locations • potential for lower cost • less concern about mobilizing buried contaminants

In-situ amendments can also be used in combination with other remedies: • possible to incorporate AC into sediment caps • apply AC during and immediately after a dredging hot spots to minimize

aqueous contaminant release from resuspended sediments and residuals.

Ghosh research group at UMBC

ACKNOWLEDGEMENTS UMBC Graduate Students and post docs:

Xueli Sun; Barbara Beckingham; Adam Grossman; Jeff Thomas; Piuly Paul, Jennifer Jerschied, Seokjoon Kwon, Sonja Fagervold

Sponsors: National Institutes of Health, US Dept of Defense, SERDP/ESTCP Programs; USEPA Great lakes National Program Office; Alcoa, USEPA SBIR program; Norwegian Research Council

Current and Past Collaborators: G. Cornelissen, D. Werner; C.A. Menzie; Cindy Gillmour; R.G. Luthy; Y-M Cho, T.S. Bridges, K. Sowers, J. E. Baker

Disclosure statement: Upal Ghosh is a co-inventor of two patents related to the technology described in this paper for which he is entitled to receive royalties. One invention was issued to Stanford University (US Patent # 7,101,115 B2), and the other to the University of Maryland Baltimore County (UMBC) (U.S. Patent No. 7,824,129). In addition, UG is a partner in a startup company (Sediment

23

Solutions) that has licensed the technology from Stanford and UMBC and is transitioning the technology in the field.