-
Danny Reible, University of Texas
-
Projected performance in various enhanced naturalrecovery
scenarios No action alternative Unamended enhanced natural recovery
AC amended enhanced natural recovery Mixed layer Thin amendment
layer (e.g. reactive core mat or surface layer)
Partitioning Assumptions Sediment shows reduced availability
according to typically
observed behavior Sorption to AC from literature Typical
bioturbation depths and rates Sensitivity to groundwater
upwelling
-
Reproduced from Ghosh et al., 2003.
7 "" ..
6 r" -
5 ,...
- ~ ~ "' ~ I
- -r"
,..
-2
1
0 ' •
-
91.00
S.OO
'tl ~
~ ~ 7.00
8 .J I;G
.9 6.00
4.00
3.00
3.00 3.5{)
!Figure 2 - tog K0w versus ~observed 1\,c All Sediment Site
IOata
D
D
X
X
D
~
4.00 4.50 5.00 16.00
Log K.,.
0 JoJil:er ;;11d Smed~. 1000
X 1-t;w;tbome 'eli: ; 1., !006
X JoJI r ;;J~d l oelm; ru, 2.001
o Klh ; lil et ; I.., lOOti
l e~- ., 2006
0 Oe>11 et ; t , 2006
- Obioerved Koc = Kow
- Obioerved Koc = 10 x low
65 0
PAHs
-
Wyckoff- Eagle Harbor
r2
-
Figure 4 - Log K0 w vs, Obs~erved log Kac
9.0
~--------------------------------------------------------------------------------~
8.5
a_o
7.5 :g
:lll!
J 1:1 ., 7.0 a D 'W
~
~ 0
6.5
D Obsel!'l.'eii Ko~~: Dat a from Anp, 2.009
6.0 IJ - OI¥se l!1.'e,d Ko~~: = Kow
-Obse~rJeii Ko~~: = 5 x Kow
5.5 ~Best Fit Line for Observed li>ata
- 95% Confidence lnteii'Val for Be-st Fit Line
5.0
~------------~------------~----------~------------~------------~------------~
s 5.5 6 6.5 7 7.5
Log !KII'il!
Log ~ va1 ues f rom Haw ker, 1988
PCBs
-
Grey/Green (1300 µg/kg) ~2 % TOC
-
ENR w/o amendment (areas not subject to scour) 720 µg/kg PCB (10
ng/L) 360 µg/kg PCB (intertidal areas) 1300 µg/kg cPAH (intertidal
areas) (6.5 ng/L)
ENR w/AC amendment 1300 µg/kg PCB (19 ng/L) 3000 µg/kg cPAH (15
ng/L)
cPAH (BaP)- Log Kow=6, Koc=10 Kow PCB (52)- LogKow=5.84, Koc=5
Kow 2%TOC
http:LogKow=5.84
-
~0 cm/yr
~1 cm/yr
~5 cm tug mixing Assumed Bioturbation 10 cm
-
Virgin AC Fouled AC PCB O-Cl LogKf 1/n Log Kf 1/n Di Cl Kow
(ng/kg)(L/ng)^1/n (ng/kg)(L/ng)^1/n 4 4.65 2 8.75 0.57 7.235 0.885
12 5.22 0 8.37 0.73 7.635 0.82 Tri b 18 5.24 2 8.23 0.7 7.4 0.8
Tetra Cl 54 5.21 4 7.88 0.86 6.89 0.94 53 5.62 3 7.53 1.08 6.87
0.995 52 5.84 2 7.82 1.03 7.02 0.99 72 6.26 1 8.39 0.83 7.62 0.79
77 6.36 0 8.9 0.82 7.96 0.765 Penta Cl 126 6.89 0 8.95 0.94 8.21
0.805
Estimated from data from Average 1/n 0.93 0.88 McDonough et al
2008
-
LogKF_AC
Log KF_DOM
Power (LogKF_AC)
Power (Log KF_DOM)
y = 0.0011x0.86 R² = 0.742
y = 7E-05x0.9222 R² = 0.8902
1
10
100
1000
1 10 100
Kf (L
/mg)
Kow
x 100000
Estimated from data from McDonough et al 2008
Fresh AC
Fouled AC
Fouled AC Fresh AC
-
720 µg/kg PCB (PCB52) – 10 ng/L AC – Log Kf ~7 (fouled), n~1 0
& 1 cm/yr deposition , 10 cm bioturbation layer Upwelling of 0
and 365 cm/yr Scenarios No Action ENR (w/o AC) 10 cm sand layer
(0.1% organic carbon)
ENR (w/AC) 0.4 lb/ft2 (~2% AC) mixed over 10 cm layer 0.4 lb/ft2
in 1 cm thin layer (e.g. RCM or unmixed layer) and 10 cm sand
layer In-Situ Treatment w/AC 0.4 lb/ft2 mixed over 10 cm
bioturbation layer Theoretical reduction in availability – 78%
-
D. I 4
EQ
n e [ J
-
.ODB -
0. I)
ll 0
D. 01.
a oo ~~~--~~~~~~~~~~~~~~ 0 2Q ~(I E:Q
TI e [ l
-
De .D n
T T ! !
DAl-02$ ! --D . ~ 2 - -
D.'IJOL5 - ·-
D.il-DlO - -
O.G C - -
D ~f: OIJ ~~~-----·~~~~·-~~~·-~~---~.• ~~~~ 0 2Q ...,(1 EJJ
1
TI e [ l
-
er1 De th = §.0
"1 ' I
7.0e-D ~ -
-
S..Oe-D 1- -
4.~ 1- ·-
3.0e-D ~ ·-
Oe:- 1- ·-
De-04 t- ·-
c o-= llC . i i I i 0 2Q .qo 6Q aJ 1
n e [ '1]
-
Hypothetical site for comparison
10 cm AC mixed layer 2% carbon
10 cm bioturbation layer
2 kg/m2 activated carbon
-
Hypothetical site for comparison
1 cm AC RCM layer 10 cm bioturbation
layer 2 kg/m2 activated
carbon
-
Slow natural attenuation of hydrophobics Minimal protectiveness
of sand cap if upwelling significant and
source maintained AC mixed into surficial sediments Substantial
reduction in availability and mobility even with AC fouling
(~78% reduction) AC mixed into cap layer Strongest reduction in
exposure and flux with ENR cap incorporating
AC More complicated placement and depth reduction
Primary uncertainties Contaminant bioavailability in existing
sediment Significance of groundwater upwelling
Contaminant partitioning and bioavailabilityOutlineSlide Number
3Slide Number 4Slide Number 5Slide Number 6PCB�DistributionsSome
Proposed Limits for ENR/AC enhanced ENRSlide Number 9Sorption onto
fresh and fouled (NOM and Biofilm AC)PCB Sorption – Correlation
with Kow (Tetra PCBs & higher)Evaluation conditionsNo Action10
cm sand capAC mixed into upper 10 cm AC mixed in 10 cm capped
layerActivated Carbon Cap �Activated Carbon Cap �Conclusions
barcode: *552496*barcodetext: SDMS Doc ID 552496
