Haley & Aldrich, Inc. 1 Strategic Data Use from Collection to Collaboration A Sediment Dredging Case Study Presented by: Ryan J. Scott, PE

Haley & Aldrich, Inc. 2 Case Study Background Soil/Sediment/Groundwater PCBs Metals DNAPL LNAPL Asbestos Site On-shore & Off-shore 100+ year history 1,500+ samples 200+ locations 26+ Acres Stakeholders Client Agencies Village Public Interest Groups Various consultants Liquid PCB Material (DNAPL)

Haley & Aldrich, Inc. 3 Case Study Background OU-1: On-shore OU-2: Off-shore 2012: Amended ROD 2012: ROD 2011: Revised FS 2012: PRAP 2009: Modified FS 2006: Supplemental FS 2003: PRAP 2003: Feasibility Study (FS) 2000: RI Report 2004: ROD 2003: PRAP 2002: Feasibility Study (FS) 2000: RI Report 1996: RI Report 1998: PRAP Integration & Collaboration 2011: Revised FS

Haley & Aldrich, Inc. 4 Collection to Collaboration Presentation Interpretation & Modeling Processing Incorporation (within the context of Collaboration) Data

Haley & Aldrich, Inc. 5 Data Processing Standardized Data Collection Create a historical database to help manage data Data Validation Create and use a Conceptual Site Model Site History, Material usage, Release mechanisms Site Specific Conditions (e.g. river and sediment dynamics) Adjust your CSM, and identify Data gaps Case Study Example… Asking why

Haley & Aldrich, Inc. 6 Data Interpretation Modeling is a process of evaluating data and rendering a physical interpretation that is intended to be consistent with actual conditions. 1.Collect and post data on site maps. 2.Choose and apply a modeling technique (kriging).

Haley & Aldrich, Inc. 7 Data Interpretation Modeling is a process of evaluating data and rendering a physical interpretation that is intended to be consistent with actual conditions. 1.Collect and post data on site maps. 2.Choose and apply a modeling technique (kriging). 3.Apply supplemental factors and professional judgment to refine the model. 4.Re-evaluate and refine the model to best fit all data. A common misconception is that a computer generated model is both ‘superior’ and ‘inherently accurate’.

Haley & Aldrich, Inc. 8 Modeling Process Example Process Two Boring Locations: Sand Clay How do we connect the Sand and Clay layers?

Haley & Aldrich, Inc. 9 Modeling Process Example Process Sand Clay Sand Clay Sand Clay Various Kriging Methods: Which one is correct?

Haley & Aldrich, Inc. 10 Add Supplemental Factors: Modeling Process Example Process Sand Clay Sand Clay Sand Clay Refine based on site factors and professional judgment Tidal Action Release Locations Sediment Deposition Rates Duration of Chemical Use Other Factors = Revised delineation of sediment contamination

Haley & Aldrich, Inc. 11 Key Principles for Datasets Invest time to build a consistent validated dataset Use supplemental knowledge to compartmentalize the data, as necessary Use your professional judgment, do not rely solely on computer generated outputs without challenging, refining and validating the results Using a model that is simple, easy to explain and understand. That will build confidence and generate trust in its interpretation

Haley & Aldrich, Inc. 12 Data Presentation Considerations: Context of the Data? Right Level of Detail? Who is your Audience/Recipients? (direct and indirect) Implications? (intended or unintended) Case Study Example… misrepresentation “A picture is worth a 1,000 words” so don’t create a figure that takes a 1,000 words to explain.

Haley & Aldrich, Inc. 13 Posted Data: (Example Section) Case Study Example: Maximum Concentration Figures Shallow Model: (0-6 inches) Deep Model:

Haley & Aldrich, Inc. 14 Data Incorporation Goals of Collaboration: Inform & educate stakeholders regarding technical issues throughout the process Get input regarding priorities and discuss cost effectiveness or approaches Question and answer Avoid an endless comment loop Initial investment: 3-4 hour in-person sessions every few weeks for 6 mo. Follow-up WebEx sessions Created around 1,500 PowerPoint slides

Haley & Aldrich, Inc. 15 Topics of Presentations & Papers Geotechnical Issues Groundwater Shoreline Protection Options Dredge Methods and Limitations Subaqueous Capping & Backfill Hydrology Toxicity evaluations Background Levels Extents of Contamination (Models and Data Gaps) Development and Selection of Remedial Alternatives Alternative Cost- Effectiveness Long Term Monitoring

Haley & Aldrich, Inc. 16 Dredging Methods Mechanical Dredge 2 Step Process Pre-clearing pass (conventional) Dredge pass (environmental) Most likely method CONVENTIONAL ENVIRONMENTAL CONVENTIONAL

Haley & Aldrich, Inc. 17 Dredge Boundary (Turbidity Control) Silt Curtain 0 20 ft MHW (EL +2.2) Recurrent HHW (EL +4.0) (upwards of EL +4.9) 2 ft Wave Heights from HHW (upwards of 5 ft possible)

Haley & Aldrich, Inc. 18 Key Principles for Effective Data Use Consider: Context, Level of Detail, Audience and Implications (intended or unintended) Collaborate: it requires an upfront investment but pays good dividends Start now: this case study started mid-stream Collaboration leads to common understanding, understanding builds confidence and confidence generates mutual respect and creates trust” Disclaimer: “Actual results may vary.” Collaboration is unique to the individuals involved.

Haley & Aldrich, Inc. 19 Results: A Positive Outcome The Revised FS was submitted to the agency and included a revised interpretation of sediment concentration data and associated modifications to the proposed remedy No questions or comments on the RFS Received favorable OU-2 and OU-1 Record of Decisions Constructable remedy with a lower estimated construction cost of over 100 million dollars Developed consensus between regulators, local stakeholders and the site owner