Sediment Cleanup Options Choosing Among Options z Regulatory

Sediment Cleanup Options Choosing Among Options z Regulatory framework for descisions (Materials courtesy of Portland Office, ACOE) z. CDF Example: Ross Island (Materials courtesy 6/7/2021 W. Fish, Portland State Universityof Copyright, 1996 © Dale Carnegie & Associates, Inc.

Quantities of Dredged Sediments z 250 million cubic yards from 25, 000 miles of navigation channels z 75 million cubic yards from permits z 325 million cubic yards each year 6/7/2021

How Much Dredged Material? > 5½ feet deep over Washington, D. C. > 1½ feet deep over Chicago 6/7/2021

Authorization z. Rivers and Harbors Act of 1899, y. Section 10 z. Clean Water Act y. Section 404 z. Marine Protection, Research, and Sanctuaries Act y. Section 103 6/7/2021

Regulatory Authorities · U. S. National Marine Fisheries Service · U. S. Fish and Wildlife Service · U. S. Environmental Protection Agency · State Fish and Game Agencies · State Water Quality Certifying Agencies · State Coastal Zone Management Agencies · Other Federal and State Agencies 6/7/2021

Federal Standard The disposal alternative or alternatives identified by the Corps which represents the least costly alternative consistent with sound engineering practices and meeting the environmental standards established by the 404(b)(1) evaluation process or ocean dumping criteria. 6/7/2021

Framework for Environmental Acceptability of Dredged Material Disposal Alternatives Evaluation of Dredging Project Requirements Identification of Alternatives Initial Screening of Alternatives Detailed Assessment of Alternatives Alternative Selection 6/7/2021

Technical Framework Summary z. Reflects real-world conditions z. Reflects aquatic, intertidal, and upland environments z. Indicates biological availability of contaminants z. Predicts potential environmental impacts z. Provides appropriate level of protection z. Is consistent with CWA, MPRSA, and NEPA 6/7/2021

ST CO MP LE XI TY / CO • Screening Tests • Predictive models TIER III • Toxicity Tests • Bioaccumulation Tests TIER IV • Chronic Sublethal Tests • Steady-State Bioaccumulation Tests • Risk Assessment 6/7/2021 ON AS IN G • Physical/Chem. data I UT OL CR E TIER II ES DR IN Data E NC • Existing HA EN TIER I

https: //www. nwp. usace. army. mil/ec/h/hr/ 6/7/2021

Basic Dredge Types z. Hydraulic y. Pipeline y. Hopper z. Mechanical y. Clamshell z. Other / Combinations 6/7/2021

Factors in Selection of Dredging Equipment z. Physical characteristics of sediments z. Quantities to be dredged z. Dredging depth z. Distance to disposal area z. Physical environment of and between areas z. Contamination level of sediments z. Method of disposal 6/7/2021

Dredged Material Disposal Alternatives z. Open Water Placement y. Ocean ~ Estuarine ~ Lakes ~ Rivers z. Confined Disposal Facilities (CDFs) y. Diked containment z. Beneficial Use Applications 6/7/2021

Beneficial Use (BU) Applications z. BU is alternative of first choice z. Needs and Opportunities z. Material Suitability z. Logistical Constraints z. Regulatory Requirements Vary 6/7/2021 y. CWA / MPRSA y. Other

Confined Disposal Facilities z. Site characterization / selection z. Engineering design z. Operational considerations z. Contaminant pathways and controls z. Long-term management z. Monitoring 6/7/2021

Confined Disposal Alternatives 6/7/2021

Engineering Issues z. Reduce Contaminant Pathways y. Disposal pathways y. Physical disturbance y. Seepage z. Optimize Capacity

Physical Disturbance z Erosion and Scour z Slope Stability y. Nature of underlying materials y. Stability of existing and future slopes z Excavation and Removal z Intended End Use of Site z Consolidation and Settlement z Cap Properties

Seepage z. Excess Pore Water z. Long Term Seepage

Other Considerations z. Dredged disposal volume z. Area of land desired z. Habitat mitigation requirements z. Cost comparisons

Ross Island 6/7/2021

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Typical Cross Section 6/7/2021

Disposal Methods 6/7/2021

Potential Contaminant Migration Pathways Disposal Processes 6/7/2021

Potential Contaminant Migration Pathways - Groundwater Transport (Present and Future) 6/7/2021

Potential Contaminant Migration Pathways Physical Disturbance 6/7/2021

Groundwater Movement through Cells 6/7/2021

Potential Groundwater Transport from Containment Cells z. Upward groundwater flow. z. Predicted discharge concentrations below risk-based criteria. 6/7/2021

Potential Physical Disturbance of Containment Cells z. Natural erosion (floods). z. Human influence (mining). z. Geotechnical stability. 6/7/2021

Slope Instability 6/7/2021

Potential Physical Disturbance of Cells z. Minimal erosion potential due to dike. z. Mining controls would avoid impacts. z. Slopes are receiving fills. 6/7/2021

Wyckoff/Eagle Harbor Bainbridge Island, in Central Puget Sound 3, 780 -acres Inactive 40 -acre wood treating facility owned by Wyckoff Adjacent 500 -acre Eagle Harbor Other upland sources of contamination (Shipyard) 6/7/2021 W. Fish, Portland State University

Wyckoff/Eagle Harbor 6/7/2021 W. Fish, Portland State University

Site History z. Shipyard operated from 1903 to 1959 on the northwest shore of Eagle Harbor, resulting in releases of metals and organic contaminants. z 1905 to 1988, wood treating operations were conducted on the southeast shore involving pressure treatment with creosote and pentachlorophenol 6/7/2021 W. Fish, Portland State University

Historical Sources z. Preservative chemicals were stored in tanks on the property. z. Contamination of soil and ground water at wood treatment facility led to seepage into adjacent sediments. z. Wastewater discharged into Eagle Harbor for many years; storing treated pilings and timber in the water continued until the late 1940's. 6/7/2021 W. Fish, Portland State University

Contaminants of Concern z. Shipyard: Levels toxic to marine life zpolyaromatic hydrocarbons (PAHs) and other organics zheavy metals such as mercury, copper, lead, and zinc 6/7/2021

Contaminants of Concern z. Wyckoff facility, soil and groundwater are contaminated with: z. Creosote z. Accompanying PAHs zpentachlorophenol (PCP) 6/7/2021

Discovery z 1984: NOAA investigations of the Harbor revealed that sediment, fish, and shellfish from Eagle Harbor contained elevated levels of PAHs z. EPA required Wyckoff to conduct environmental investigation activities under RCRA, and the state required immediate action to control stormwater runoff and seepage of contaminants 6/7/2021 W. Fish, Portland State University

CERCLA Operable Units z 1991, EPA defined three operable units at the Wyckoff/Eagle Harbor site: z. Wyckoff (OU 1) z. East Harbor (OU 2) z. West Harbor (OU 3) z. Wyckoff Facility groundwater (OU 4, 1994) 6/7/2021 W. Fish, Portland State University

East Harbor Capping (OU 2) z. Sept 1993 -March 1994, EPA and the Corps of Engineers covered contaminated sediments in the East Harbor z. Cap of clean sediment at water depths of 17 m and 13 m, respectively. z. Sediment was dredged from the Snohomish River as part of an annual project for ship navigation 6/7/2021 W. Fish, Portland State University

Capping Methods z. Split Hull: Fast but uneven. 6/7/2021 W. Fish, Portland State University

Capping Methods z. Hydraulic washoff: 6/7/2021 W. Fish, Portland State University

West Harbor CDF (OU 3) 6/7/2021 W. Fish, Portland State University