A Retrospective Analysis of Sustainability Metrics for Remedial Alternatives at 2 Sediment Remediation Sites Amanda D. McNally, PE (AECOM) Frank J. Messina (ExxonMobil Environmental Services Company) 4 th International Conference on Sustainable Remediation Montreal, Quebec, Canada April 26, 2016
Presentation Outline – Background – Overview of Selected Sediment Sites – Sustainability Assessment Tools & Methods – Results & Comparative Analysis – Observations & Lessons Learned Sediment GSR Tools April 26, 2016 Page 2
Sustainability Goes Beyond Green Remediation – “Green” Remediation (USEPA; various documents) Implementation • Practice of considering all environmental effects of remedy Remedy implementation and incorporating strategies to maximize net environmental benefit • The goal is not to change the remedy selection criteria but to incorporate sustainability into the process – “Sustainable” Remediation • The practice of demonstrating, in terms of environmental, Selection economic and social indicators, that the benefit of undertaking Remedy remediation is greater than its impact, and that the optimum remediation solution is selected through the use of a balanced decision-making process.” (Sustainable Remediation Forum - United Kingdom) Sediment GSR Tools April 26, 2016 Page 3
Why is This Important: Example Effect of BMPs is Incremental Compared To Remedy Selection 6000 5000 Tons CO2 4000 3000 2000 BMP reduction 1000 With BMPs 0 Reference: Lower Duwamish Waterway Feasibility Study (AECOM, 2012) Note: Unit emissions are given for a 10 acre site with 5 feet contamination depth, 50% volume creep, transportation to and disposal at Roosevelt Landfill, 50% open water disposal, and 50% beneficial reuse. BMPs include finer tolerances, maximize rail use, and use of biofuels in trucks Sediment GSR Tools April 26, 2016 Page 4
Demands of Sediment Sites Make a Case for Action – Sediment remediation is complex; costs and benefits not always balanced; remedies take too long and are focused on mass removal – Sustainability already has a place in the remedy selection process • Consistent with CERCLA and state regulations (e.g., NY, others) • Net Environmental Benefits Analysis (NEBA) is one of many proven tools that should be part of a Sustainability Assessment – Sustainability should be part of the weight-of-evidence approach for selecting remedial actions • Most effective when considered early, as part of the selection process • May easily be incorporated into remedial design and implementation • Provides a platform for stakeholders to evaluate trade-offs (costs, risks, benefits) and make informed decisions Sediment GSR Tools April 26, 2016 Page 5
Retrospective Analysis Demonstrates Value of Sustainability Assessments in Remedy Selection – Objective : Conduct sustainability assessment for several large sediment remediation projects with remedies selected over 10 years ago (pre-SURF) to demonstrate that sustainability should be considered in remedy selection process – Why : Selected remedies for complex sediment sites often focus on mass removal, take years to implement, and require expenditures well beyond the point of diminishing return – Benefit: Newly established sustainability tools provide a structured platform for stakeholders to evaluate trade-offs (costs, risks, benefits) and make informed decisions within the CERCLA framework Sediment GSR Tools April 26, 2016 Page 6
Methods
Representative Sites for Evaluation Site #1: Hudson River Polychlorinated Biphenyls (PCBs) Superfund Site • Extends nearly 200 miles along the Hudson River • ROD issued February 2002 • Phase 1 dredging completed from 2009-2015 Site #2: Lower Fox River PCBs Superfund Site (OU3) • 39 miles from Lake Winnebago to Green Bay • Focus on Operating Unit 3, Little Rapids to De Pere • ROD issued June 2003 • OU3 dredging completed from 2009-2011 Sediment GSR Tools April 26, 2016 Page 8
Projects Preceded EPA Green Remediation Policies SURF est. USEPA Region 2 USEPA Superfund SiteWise TM Clean & Green Green Remediation V3.1 Policy Strategy 2010 2015 2000 2005 Hudson River Phase 1 Feasibility Study & Proposed Plan Lower Fox River Feasibility Study OU3 & Proposed Plan Construction Durations Sediment GSR Tools April 26, 2016 Page 9
Hudson River FS Alternatives Dredge Cost Dredge Cap PCB Mass Construction Volume Estimate Remedial Area Area Removal Time (cubic (US million Alternative (acres) (acres) (kilograms) (Years) yards) $) Alt 1 1,732,820 493 207 33,100 $338 5 Alt 2 (EPA Selected) 2,651,730 493 0 45,600 $413 5 Alt 3 3,823,060 964 0 >63,500 $570 7 Most sustainable alternative determined in this assessment References: Hudson River PCBs Reassessment RI/FS Phase 3 Report: Feasibility Study (December 2000); Hudson River PCBs Superfund Site Proposed Plan (December 2000) Sediment GSR Tools April 26, 2016 Page 10
Lower Fox River FS Alternatives Dredge Cost Dredge Cap PCB Mass Construction Volume Estimate Remedial Area Area Removal Time (cubic (US million Alternative (acres) (acres) (kilograms) (Years) yards) $) Alt 1 (Dredge, 776,791 498 0 1,157 118.3 0.9 500ppb) Alt 2 (Dredge, 586,788 328 0 1,111 99.9 0.7 1,000 ppb) (Selected) Alt 3 (Cap to max. 170,858 193 135 764 62.9 1.3 extent) Most sustainable alternative determined in this assessment References: Final Feasibility Study, Lower Fox River and Green Bay, Wisconsin Remedial Investigation and Feasibility Study (December 2002) ; Proposed Remedial Action Plan, Lower Fox River and Green Bay (October 2001) Sediment GSR Tools April 26, 2016 Page 11
Applied 3 Different Established Tools to the Sites 1) SiteWise TM (Version 3.1) • Environmental and safety metrics • Publically available tool developed by Battelle for US Navy • Version 3.1 released in 2015 with sediment remediation modules 2) AECOM Sustainability Tool (AST) • Environmental footprint for sediment alternatives • Designed in 2012 for Lower Duwamish Waterway Feasibility Study • Proprietary Excel-based tool developed by AECOM 3) AECOM Qualitative Sustainable Remediation Tool (AqSRT) • Tiered, ranking approach to site assessment • Scores environmental, social, and economic values • Developed by heritage URS in 2011 based on SuRF-UK indicators Sediment GSR Tools April 26, 2016 Page 12
Quantitative and Qualitative Metrics Evaluated Model #1: SiteWise TM Model #2: AECOM Model #3: AECOM qSRT Tool GHG (CO 2 , CH 4 , N 2 O) CO 2 Emissions Impacts on Air Impacts on Soil Conditions Emissions CO Emissions Impacts on Ground & Surface Water Energy Energy Impacts on Ecology Use of Natural Resources & Waste NO x Emissions NO x Emissions SO x Emissions SO x Emissions Impacts on Human Health & Safety Ethics & Equality PM10 Emissions PM10 Emissions Neighborhood & Locality Landfill Landfill Communities & Community Involvement Ecological Footprint Uncertainty & Evidence Accident Risk – Fatality Direct Economic Costs & Benefits & Injury Accident Risk – Indirect Economic Costs & Benefits Employment & Employment Capital Lost Hours – Injury Fatality & Injury Induced Economic Costs & Benefits Project Lifespan & Flexibility Color indicates pillar of sustainability: Environmental / Social / Economic The two footprint tools evaluate similar metrics and the results can be compared between the two. The AST tool also includes an ecological footprint metric. The third tool is qualitative and looks at environmental (blue), social (purple), and economic (green) considerations. Sediment GSR Tools April 26, 2016 Page 13
Results & Comparative Analysis
Hudson River Superfund Site Results Model #1: SiteWise TM Impacts of Remedial Alternatives (Normalized to highest impact alternative) 100% 80% 60% 40% 20% 0% Selected Alt. 1 Cap-3-10-Select Alt. 2 Rem-3-10-Select Alt. 3 Rem-0-0-0 Alternative Sediment GSR Tools April 26, 2016 Page 15
Hudson River Superfund Site Results Model #2: AECOM Tool Impacts of Remedial Alternatives (Normalized to highest impact alternative) 100% 80% 60% 40% 20% 0% Selected Alt. 1 Cap-3/10/Select Alt 2. Rem -3/10/Select Alt. 3 Rem-0/0/0 Alternative Sediment GSR Tools April 26, 2016 Page 16
AECOM qSRT (Model #3) – Weight & Rank Each Indicator Remediation Option Assessment Criteria Weight 1 2 3 Impacts on Air 2 10 6 2 Impacts on Soil and Ground Conditions 5 15 15 20 Environ- Impacts on Groundwater and Surface Water 3 12 9 9 mental Impacts on Ecology 4 12 12 8 Use of natural Resources and Waste 3 12 6 3 TOTAL 17 61 48 42 Impacts on Human Health and Safety 5 20 15 10 Ethics and Equality 3 6 9 9 Social Neighborhood and Locality 4 12 12 8 Communities and Community Involvement 4 20 20 20 Uncertainty and Evidence 2 8 8 8 TOTAL 18 66 64 55 Direct Economic Costs and Benefits 2 6 4 2 Indirect Economic Costs and Benefits 2 2 2 4 Economic Employment and Employment Capital 3 6 6 9 Induced Economic Costs and Benefits 3 3 3 3 Project Lifespan and Flexibility 5 15 20 20 TOTAL 17 61 48 42 Overall (Average) Sustainability Score 62.6 53.3 46.3 Sediment GSR Tools April 26, 2016 Page 17
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