A.10 Eagle (East) Harbor, Wycoff, WA

A.10.1 Summary

Environment:	Marine
Scale:	Full
Contaminants of Concern:	Residue from wood treating facility: creosote, PCP, PAHs. Heavy metals: mercury, lead, copper, zinc
Final Remedy:	Sediments were dewatered on an asphalt-treated base work area pad, which drained into a sump that was pumped to storage tanks. Removal and disposal were in an on-site CDF of hotspot sediments containing more than 5 milligrams per kilogram (mg/kg) total mercury. Materials greater than two inches in diameter were disposed of off site at Olympic View Landfill.

 

A.10.2 Site Description

Wycoff, WA

Year: 1997

Water Depth: 15–45 ft

Target Volume: Projected Mercury impacted area: 1,500–9,000 yd³

A.10.3 Remedial Objectives

• anthracene 1,200 mg/kg
• chrysene 460 mg/kg
• naphthalene 170 mg/kg
• pyrene 1,400 mg/kg
• mercury 0.58 mg/kg

Contaminated sediment thickness: up to 0.7 yards deep

A.10.4 Remedial Approach

Dredged using front end loader and clamshell bucket. Sediments were dewatered on an asphalt-treated base work area pad, which drained into a sump that was pumped to storage tanks. Materials greater than 2 inches in diameter were disposed of off site at Olympic View Landfill.

Removal and disposal in an on-site CDF of hotspot sediments containing more than 5 milligrams per kilogram (mg/kg) total mercury.

Demolition and removal of buildings, structures, above and underground storage tanks, underground foundations and piping, and removal of asbestos, sludge, and heavily contaminated soil.

New aquatic habitat constructed to mitigate loss of 0.9 acres from remedial construction.

A.10.5 Monitoring

Resuspension during dredging operation. No details on resuspensionA renewed suspension of insoluble particles after they have been precipitated. controls for this site. Most activities were performed at extreme low tide. Sheet piling was used to withhold water from the dredging areas.

Performance:

Goals were met. Concerns exist for future protectiveness of habitat/water quality.

Residuals:

All dredged areas backfilled with clean sediment to pre-existing grade elevations.

Placement of thick capA covering over material (contaminated sediment) used to isolate the contaminants from the surrounding environment. (1 meter) over sediments containing >2.1 ppm mercury; and placement of thin cap (15 centimeters) over sediments exceeding chemical or biological cleanup standards.

PAH intertidal area monitored for 10 years to allow natural recovery.

A.10.6 References

Declaration for the Record of Decision. http://web.cecs.pdx.edu/~fishw/ECR_WyckoffEagleSumm.pdf.

USEPA Five-Year Review Report Wyckoff/Eagle Harbor Superfund Site. Sep 2002. http://www.epa.gov/superfund/sites/fiveyear/f02-10002.pdf.

U.S EPA. Second Five-Year Review Report for the Wyckoff/Eagle Harbor Superfund Site Bainbridge Island, Washington. Sep 2007. http://www.epa.gov/superfund/sites/fiveyear/f2007100001727.pdf.

Major Contaminated Sediment Sites Database; Sept. 2004 as updated 2008. http://www.smwg.org/MCSS_Database/MCSS_Database_Docs.html.

Publication Date: August 2014