ITEM NO.  __7b_Supp______
DATE OF
MEETING October 12, 2010
Briefing on the Lower
Duwamish Waterway
Superfund Site

Briefing Summary
Cleanup required of contamination in Lower
Duwamish to protect human health and
ecological environment
Feasibility Study presents array of alternatives to
conduct cleanup
All alternatives predicted to protect environment
in long term  90% reduction in PCBs achieved
Short term differences include impacts of
actions, length of time to reduce risk, and cost
EPA and Ecology will select cleanup alternative
2

Lower Duwamish Waterway
Superfund Site
Industrial and Cultural Legacy, Economic
Engine, Growing Communities
5-mile stretch, about 441 acres, range
of industrial contaminants
Listed as Superfund site in 2001
Studies define contamination and risk
LDWG invested $40 million to move
process forward, and is pursuing early
action cleanups of prioritized
contaminated areas
Duwamish Valley supports over
100,000 jobs and 80% of City's
industrially-zoned land
3

Roles and Responsibilities
Regulatory
Agencies


Sampling
Lower Duwamish                                    Studies
Waterway Group                                     Plans
(LDWG)                                      Analyses
Cost Sharing
4

Getting Oriented  Sediment
Contamination and Early Action Areas

Risk Drivers
PCBs   40+ state
Arsenic "sediment
management
Dioxin    standard"
cPAHs   chemicals
Five Early Action Areas
under way (hatched)
Remaining hot spots
require cleanup
(yellow)
5


Key milestone: October 15
Getting closer to cleanup decision
Draft Final Feasibility Study
October 15 www.ldwg.org
FS edited with significant
EPA/Ecology input
Focused agency and public
Cover of FS
review through end of year
Public input key to regulators
selecting preferred cleanup
alternative
Stakes are high  time is now
to engage region and provide
input
6

Cleanup Goals
Seafood Consumption       Worms and Benthic
Invertebrates

Direct Contact with
Contaminants               Fish and Wildlife

Cleanup goal is to reduce risk.
How will we go about It?
7

Risk Levels in Lower Duwamish:
Baseline Risk Assessment



8

Alternatives in FS
12 Alternatives developed and evaluated
in FS
Alternatives vary by:
Types of technologies (dredge or cap)
Size of footprint requiring action
Amount of natural processes vs. active
Predicted time to reduce risk in sediment (12
to 43 year)
Certainty of time to reduce risks
Cost (200 Mil to 1,330 Mil)
9

Multiple Technologies Available



10

All Alternatives Designed to
Meet Cleanup Objectives



11

Alternatives Vary in Time to Meet
Objectives
Alternative                               Time to Meet All Objectives
12 years
4C
13 years
5C
3C                                  14 years
3R                                        16 years
18 years
4R
19 years
2R CAD
19 years
2R
6C                                                           23 years
5RT                                                              24 years
5R                                                              24 years
43 years
6R

12

Range of Alternatives Evaluated 
Varying technologies and footprints
EXAMPLES: Alternative 4 actively remediates 143 acres (full range is 29-328
acres)
Alternative 4 -                        Alternative 4 -
Combined Technology             Removal Emphasis
(4C)                             (4R)


Construction time: 7 yrs                               Construction time: 13 yrs
Dredging Volume: 560,000 cy                      Dredging Volume: 1,100,000 cy
Restoration timeframe: 22 yrs                          Restoration timeframe: 23 yrs
Base Case Cost: $280 million                       Base Case Cost: $450 million
Range of Costs: $210 to $390                        Range of Costs: $360 to $630
million                                                  million
Primary Differences:
"Combined" alternatives emphasize mix of active technologies.
"Removal" alternatives focus more on dredging rather than other active technologies.
Costs range from $200 million to $1.3 billion, construction timeframes from 4-38 years.
(Note: handout with more detailed charts)
13

Reduction in PCBs achieved in
different ways



14

Tradeoffs to Consider 
"Combined" vs. "Removal"
Dredging
Considered more permanent in long term
Causes most impact during construction
Larger dredge volumes mean longer construction,
truck/train transport impacts (traffic, emissions), community
and worker impacts
Non-dredge methods (capping, engineered and
monitored natural recovery)
Get done faster and cheaper
Less short-term impacts than dredging
May require more maintenance over time
All technologies require monitoring to ensure they are
functioning as intended

15

Moving toward Cleanup
2010     2011      2012      2013     future
Review period Draft Final Feasibility
Study (10/15/10  12/17/10)
Public meeting on Feasibility Study
(12/9/10)
Agreement on approved Final
Feasibility Study (May-July 2011)
Agency community and stakeholder
outreach (July-Dec 2011)
Likely liability allocation (2011-2013)
Agency proposed plan for public review
(Jan 2012)
EPA and Ecology decision on remedy
(Jan 2013)
Design, construction, monitoring
(2013-ongoing)
Source control implemented (ongoing)
Public involvement and outreach
(ongoing)
Early actions (2011-beyond )
16

Funding Impacts to Region
Range of cleanup costs large, and don't include
other support activities (source control, EAAs)
Liability will likely be allocated broadly
Public agency projections of impacts to tax and
ratepayers are being developed
Local and regional businesses will absorb costs,
potential impacts on business health and
investment
Uncertain availability of MTCA grant money to
local governments
17

Key Stakeholders are Involved
EPA and Ecology
U.S. Army Corps, NOAA, U.S. Fish and
Wildlife
WDFW and DNR
Tribes
Duwamish River Cleanup Coalition (DRCC)
Local residents and businesses
Potentially responsible parties
Seattle and King County ratepayers/taxpayers
18

Community Outreach Is
Ongoing
Joint outreach to community groups with EPA,
Ecology, DRCC
Outreach to non-English speaking communities
ECOSS hosting business meetings
Web-based availability of documents and online
comment opportunity
EPA/Ecology public meeting December 9

19

Briefing Summary
Revised Feasibility Study moves us closer to a
cleanup decision
Moving forward with cleanup is critical to reduce
risks to community and environment
Alternatives vary in time, impacts, and cost
Funding impacts to businesses, Port, and
municipalities
EPA and Ecology will select cleanup alternative
that best meets their objectives
20

www.portseattle.org