ERDC/EL TR-08-29 Technical Guidelines for Environmental Dredging of Contaminated Sediments Michael R. Palermo, Paul R. Schroeder, Trudy J. Estes, September 2008 and Norman R. Francingues Environmental Laboratory Environmental Approved for public release; distribution is unlimited. ERDC/EL TR-08-29 September 2008 Technical Guidelines for Environmental Dredging of Contaminated Sediments Michael R. Palermo, Paul R. Schroeder, Trudy J. Estes, and Norman R. Francingues Environmental Laboratory U.S. Army Engineer Research and Development Center 3909 Halls Ferry Road Vicksburg, MS 39180-6199 Final report Approved for public release; distribution is unlimited. Prepared for U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response Washington, DC 20314-1000 ERDC/EL TR-08-29 ii Abstract: This report provides technical guidelines for evaluating environmental dredging as a sediment remedy component. This document supports the Contaminated Sediment Remediation Guidance for Hazardous Waste Sites, released by the U.S. Environmental Protection Agency (USEPA) in 2005, by providing detailed information regarding evaluation of environmental dredging as a remedy component. This document is intended to be applicable to contaminated sediment sites evaluated under various environmental laws and regulatory programs. The intended audience for this report includes all stakeholders potentially involved in evaluating environmental dredging for purposes of a feasibility study, remedial design, and implementation. The scope of this document is limited to the technical aspects of the environmental dredging process itself, but it is important that environmental dredging be integrated with other components such as transport, dewatering, treatment, and rehandling and disposal options. This report covers initial evaluation, pertinent site conditions and sediment characteristics, environmental dredging performance standards, equipment capabilities and selection, evaluation of production, duration, and transport, methods for estimating resuspension, residuals and release, control measures, operating methods and strategies, and monitoring. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR. ERDC/EL TR-08-29 iii Contents Figures and Tables...............................................................................................................................viii Preface.....................................................................................................................................................x Unit Conversion Factors...................................................................................................................... xii 1 Introduction..................................................................................................................................... 1 1.1 Background........................................................................................................................ 1 1.2. Purpose, scope, and applicability .................................................................................... 2 1.3. Environmental dredging objectives and processes ........................................................ 3 1.4. Evaluation sequence for environmental dredging .......................................................... 5 2 Initial Evaluation...........................................................................................................................17 2.1. Conditions conducive to dredging.................................................................................. 17 2.2. Potential advantages and limitations of dredging ........................................................18 2.3. Environmental dredging as a component of a sediment removal remedy..................20 2.4. Evaluation of project requirements and constraints ....................................................22 2.5. Preliminary evaluation of dredging feasibility ...............................................................23 2.6. Pilot studies ....................................................................................................................24 3 Evaluating Site Conditions and Sediment Characteristics .....................................................26 3.1. Identifying and filling data gaps..................................................................................... 27 3.1.1. General considerations for site and sediment characterization ..................................27 3.1.2. Conceptual site model ....................................................................................................29 3.2. Site conditions ................................................................................................................30 3.2.1. Project setting and sources of contamination...............................................................31 3.2.2. Positioning and survey control .......................................................................................31 3.2.3. Access to the water body................................................................................................32 3.2.4. Waterway uses and infrastructure .................................................................................32 3.2.5. Siting for transport, rehandling, treatment, and disposal.............................................34 3.2.6. Water depths and bathymetry........................................................................................35 3.2.7. Hydrodynamics................................................................................................................36 3.2.8. Elevation and nature of bedrock or hard bottom ..........................................................37 3.2.9. Shoreline stability............................................................................................................38 3.2.10. Presence and extent of debris .....................................................................................39 3.2.11. Habitat considerations and seasonal dredging restrictions.......................................42 3.2.12. Winter icing conditions .................................................................................................43 3.2.13. Ambient water and air quality ......................................................................................43 3.3. Sediment characterization.............................................................................................44 3.3.1. Sampling plans and data quality....................................................................................44 3.3.2. Positioning and vertical survey control for sampling.....................................................46 3.3.3. Sediment sampling equipment and techniques............................................................47 3.3.4. Core compression, segmentation, and compositing.....................................................48 ERDC/EL TR-08-29 iv 3.3.5. Sediment physical properties.........................................................................................50 3.3.6. Sediment contaminant concentrations .........................................................................52 3.4. Removal requirements ...................................................................................................53 3.4.1. Debris removal ................................................................................................................53 3.4.2. Dredgeability....................................................................................................................55 3.4.3. Volume to be dredged.....................................................................................................56 4 Environmental Dredging Performance Standards ...................................................................58 4.1. Goals, objectives, and performance standards ............................................................58 4.2 Performance standards related to production and implementation time....................61 4.2.1. Time of project completion .............................................................................................61 4.2.2. Limits on solids content and volume throughput..........................................................62 4.3. Performance standards related to resuspension and release ....................................63 4.3.1. Sediment resuspension ..................................................................................................63 4.3.2. Water quality standards..................................................................................................63 4.3.3. Air quality standards .......................................................................................................64 4.4. Performance standards related to dredging effectiveness..........................................65 5 Equipment Capabilities and Selection.......................................................................................66 5.1. Dredging