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Wyckoff Eagle Harbor Site
Public Information Meeting December 10, 2014
Helen BottcherEPA Project Manager
Provide a status update Describe cleanup alternatives under
consideration Answer your questions Hear informal input
No cleanup decision has been made! Formal public comment will be solicited in
Summer 2015 when EPA releases the Proposed Plan
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Ecology◦ Chung Yee, Barry Rogowski, Sandra Caldwell,
Susannah Edwards, Dawn Hooper Floyd | Snider – Ecology Consultant◦ Kate Snider
CH2M Hill – EPA Contractor◦ Ken Scheffler, Jeff Gentry, George Hicks
EPA◦ Helen Bottcher, Rene Fuentes, Kira Lynch, Peter
Murchie, Beth Sheldrake
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(b) (6)
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• 1984 – EPA orders Wyckoff Company to conduct environmental investigation
• 1987 – Site added to the Superfund List• 1994 – Legal settlement with Pacific Sound
Resources for Superfund liability • Cleanup Decisions
• 1994 – Groundwater ROD (interim)• 1994 – Offshore / Eagle Harbor ROD• 2000 – Soil and Groundwater ROD• 2007 – West Beach ESD
1990: groundwater extraction, treatment begins 1992 – 1994: significant cleanup actions to remove
contaminated soils, repair bulkhead, recycle materials in tanks, treatment equipment
1994: upgrades to groundwater extraction system and treatment plant
1996 – 1997: removal of site structures 2000 – 2001: perimeter sheet pile wall 2002 – 2003: thermal treatment pilot study 2010: replaced groundwater treatment plant 2012 - 2013: new investigation of subsurface
contamination
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1993 -1994: 54 acres of Eagle Harbor capped 1999: West Dock removed 2001: perimeter sheet pile wall 2001 - 2002: extended sediment cap along
west side of site 2008: completed West Beach cap 2013: completed new investigation of
contamination remaining in the beaches
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WA Department of Ecology operates groundwater extraction and treatment plant
Groundwater is pumped from shallow aquifer, treated, discharged to Eagle Harbor
Containment is effective, but running the pump and treat system is expensive ($800,000/yr)
2010: Ecology completed Generational Remedy Evaluation
Current remedy evaluation seeks more permanent and cost effective solution
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Wyckoff Point FFS Project Area
Wyckoff Beaches FFS Project Area
NAPL = Non-Aqueous Phase Liquid
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Screened available remedial technologies Bundled technologies in cleanup alternatives◦ All the alternatives rely on more than one
technology Developed conceptual design and rough
duration, cost estimates for each alternative Alternatives compared to one another in Draft
Focused Feasibility Study (FFS) reports
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Mobilizing equipment to the site, obtaining permits, developing health and safety plans
New sheet pile and concrete perimeter wall New Access Road from Eagle Harbor Drive down to the
site Excavation and removal of buried concrete and other
debris Construction of new outfall Final site cap Costs are not insubstantial:◦ Range from $35 to $52 million
No cleanup action will get the upland soil and groundwater so clean that we can allow it to erode into Eagle Harbor
Wall needed to support future use as a park Wall needs to be replaced – this will involve
installation of a second metal wall and concrete bulkhead
2 options on the table: put the new wall inside (land side) of the existing wall, OR build it out onto the beach
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1. No further action2. Containment (the current remedy)3. Excavation, Thermal Desorption, and In Situ
Chemical Oxidation 4. In-Situ Solidification / Stabilization (ISS)5. Thermal Enhanced Extraction and ISS6. Partial excavation, Thermal Desorption, and
Thermal Enhanced Extraction7. ISS of Core Area + NAPL recovery
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North/East/Periphery Shallow (LNAPL) Areas
Core Area
North Deep (DNAPL) Area
10% RE Footprint
Currently includes the area within the upper aquifer where NAPL is present (TarGOST >10% RE).
Description: Solidification through concrete mixing of virtually all the mobile NAPL.
95% of NAPL would be treated Remaining 5% of NAPL addressed through
natural attenuation and passive groundwater treatment
Cost: $64M to $138M
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Description: NAPL recovery through an expanded network of groundwater wells, enhanced with heat (steam injection) in the core area, north shallow and east shallow areas. ISS in the north deep area, using jet grout mixing.
Enhanced Aerobic Biodegradation (EAB) in peripheral areas, and to “polish” treated zones
Cost: $104M to $224M
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Phase 1: ISS of an expanded “core” area. NAPL recovery in other areas with EAB. Passive groundwater treatment for residual contamination.
Phase 2 (only if needed): Thermal enhanced “wet steam” injection and NAPL recovery, continued EAB and passive groundwater treatment.
Cost: $38M to $82M (~ $55M for Phase 1 only)
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Questions about Upland Treatment Options ?
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Alternative 1 – No Action Alternative 2 - Seep Patches and Monitored
Natural Recovery (MNR) Alternative 3 – Thin Inset Caps and MNR Alternative 4 - Vertical Containment with Thin
Caps and MNR Alternative 5 – Dredging with Thick Caps and
MNR
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Active Remedial Technologies for
Seeps and Potentially Mobile NAPL Zones
(brown areas)
Monitored Natural Recovery (MNR) for Non-Mobile NAPL
Zones (dark green areas)
Existing Phase III Cap
Shallow excavation of active product seeps only Monitored Natural Recovery (MNR) over rest of
beaches Excavate, dewater, and inset cap during low tide ◦ Approximately 15 40 x 40 foot areas◦ 30-inch cap with amended base layer
Dewater, stabilize, landfill or potentially upland dispose of excavated materials
Cost: $8.0M to $17.0M
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AC- and OC-amended caps placed over areas with suspected mobile NAPL and North Shoal Surface Sheen Area
Excavate, dewater, and inset cap during low tide ◦ Approximately 70 40 x 40 foot areas◦ 30-inch composite cap profile ◦ Dewater, stabilize, landfill or potentially upland dispose of
excavated materials Long-term O&M ◦ Up to 50% percent of cap replaced over first 50 years
Cost: $10.2M to $21.8M
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• Amended caps (cross hatch) placed over suspected mobile NAPL zones (brown) and North Shoal sheening area
• Other mobile NAPL zones shown are deeper and not amenable to capping
New Seep Area Discovered May 2014*
Shallow NAPL Area*
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Temporary sheet pile enclosures to contain dredging◦ Driven to about 25 feet below beach grade◦ Sediments removed to about 10 feet below beach grade◦ Dredges positioned inside enclosure with standing water column
Backfilled with capping materials◦ OC-amended lift placed at base of dredge prism◦ Gravelly sand backfill placed to beach surface
Dewater/stabilize, and landfill or potentially upland dispose of dredged materials
Long-term monitoring but no repair/replacement envisioned Cost: $32.0M to $68.5M
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• Temporary sheet pile enclosures (gray lines) placed around suspect mobile NAPL zones
• East Beach removal may be completed from land
• North Shoal areas to be refined in design
Questions about Treatment Options for the Beaches ?
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Long-Term Effectiveness and Permanence
Reduction of TMV
Balancing Criteria
Short-term Effectiveness
Implementability
Cost
Threshold Criteria
Protection of HH and Environment
Compliance with ARARs
Pass Pass
Rating
Rating
Rating
Rating
Rating
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Threshold criteria evaluated using:◦ Pass (yes) ◦ Fail (no)
Alternatives that failed threshold criteria not carried forward for balancing criteria evaluation
Primary Balancing Criteria◦ 3. Long-term effectiveness and permanence◦ 4. Reduction of toxicity, mobility or volume through
treatment◦ 5. Short-term effectiveness◦ 6. Implementability◦ 7. Cost
Balancing criteria evaluated:◦ Narratively◦ Rating provided using the following:
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Modifying criteria◦ 8. State/Support agency acceptance◦ 9. Community acceptance
These criteria are assessed formally after the public comment period on the Proposed Plan.
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EPA National Remedy Review Board Choose preferred alternative for both areas Determine how best to combine the remedies
for the two areas Publish the final FFS Reports Develop the Proposed Plan
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Phasing and Sequencing◦ Which first: offshore or upland?
Which wall replacement design? Opportunities for efficiencies or cost savings◦ Possible disposal of beach sediment in the upland portion of
the site Will develop recommended sequence, duration
estimates for Proposed Plan
Proposed Plan available for public review and comment - Summer 2015◦ Notice in newspaper◦ Formal public meeting(s)◦ Opportunity for verbal and written comment
Final FFS document will be made available at the same time
Join our Mail List Record of Decision Winter 2015
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Thank you for coming! Questions?
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