Lower Duwamish Waterway Superfund Site Proposed Plan Feb ... · Plan, Figure 14 pg. 63 62% 20% 6%...
Transcript of Lower Duwamish Waterway Superfund Site Proposed Plan Feb ... · Plan, Figure 14 pg. 63 62% 20% 6%...
Lower Duwamish
Waterway Superfund Site
Proposed PlanApril 15, 2013
ESC, LLC
Dr. Peter deFur
Four Cleanup Objectives
Protect people from contaminated fish
Protect people from contaminated sediment
Protect wildlife from contamination
Protect bottom dwelling animals
http://bioweb.uwlax.edu/bio203/s2009/lu
chterh_wesl/dungcrab.jpg
Protect Wildlife from Contaminants
Protect animals that live on the bottom
Proposed Plan pg. 49
Dredging: removal
Enhanced recovery: additives
Capping: cover
Natural recovery: Let It Be
Institutional Controls – no fishing
Few options to clean up the river...
The Preferred Alternative (5C Plus) will address approx. 412 acres
Not including 29 acres of cleanup in Early Action Areas (EAAS)
?Institutional Controls – such as fish advisories?
Preferred Alternative Remediation Elements
84
24
48256
Dredging
Capping
Enhanced NaturalRecovery
Monitored NaturalRecovery
For more
comparison of
alternatives see
Proposed
Plan, Figure 14
pg. 63
62%
20%
6%
12%
Permanence
Certa
inty
Dredge
Cap
Enhanced natural recovery
Monitored natural recovery
1E-08
1E-07
1E-06
1E-05
1E-04
1E-03
1E-02
1 meal every other month
1 meal per month
1 meal per week
3 meals per week*
Excess C
an
cer
Ris
ks f
or
PC
Bs
Risks at LDW baseline concentrations
The shaded area indicates EPA's acceptable excess
cancer risk range under CERCLA. The dotted line
indicates the MTCA threshold for individual carcinogens.
1 in 100
1 in
100,000,00
0
1 in
1,000,00
0
1 in
10,000
Excess Cancer Risks for PCBs for Tribal Child
Source: EPA, Hiltner, April 5, 2013
0
2
4
6
8
10
12
14
1 meal every other month
1 meal per month
1 meal per week
3 meals per week*
No
n-C
an
cer
HQ
s f
or
PC
Bs HQ at LDW baseline concentrations
HQ at model-predicted steady-state concentration
The dotted line indicates the CERCLA
and MTCA non-cancer threshold.
8127
Non-cancer hazard quotients for PCBs for Tribal child
Source: EPA, Hiltner, April 5, 2013
Source Control from many places
Proposed Plan pg. 4
Figure 1
Lower Duwamish Waterway and Early Action Areas
Sources from the Green River
Map of relevant locations on the Green River upstream of the Lower Duwamish Waterway Superfund Site in Seattle, WA
Quality Assurance Project Plan (QAPP) pg. 11
Questions?????
At the end