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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)
April 26, 2016
4th International Conference on Sustainable Remediation
Montreal, Quebec, Canada
Presentation Outline
– Background
– Overview of Selected Sediment Sites
– Sustainability Assessment Tools & Methods
– Results & Comparative Analysis
– Observations & Lessons Learned
April 26, 2016 Sediment GSR Tools Page 2
Sustainability Goes Beyond Green Remediation
– “Green” Remediation (USEPA; various documents) • Practice of considering all environmental effects of 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,
economic and social indicators, that the benefit of undertaking 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)
April 26, 2016 Sediment GSR Tools Page 3
Rem
edy
Impl
emen
tatio
n R
emed
y Se
lect
ion
Why is This Important: Example Effect of BMPs is Incremental Compared To Remedy Selection
April 26, 2016 Sediment GSR Tools Page 4
0
1000
2000
3000
4000
5000
6000 To
ns C
O2
BMP reduction
With BMPs
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
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
April 26, 2016 Sediment GSR Tools 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
April 26, 2016 Sediment GSR Tools 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
April 26, 2016 Sediment GSR Tools Page 8
Projects Preceded EPA Green Remediation Policies
April 26, 2016 Sediment GSR Tools Page 9
2000 2010 2015 2005
Lower Fox River Feasibility Study & Proposed Plan
Hudson River Feasibility Study & Proposed Plan
Phase 1
OU3
Construction Durations
USEPA Superfund Green Remediation
Strategy
USEPA Region 2 Clean & Green
Policy
SiteWiseTM V3.1
SURF est.
Hudson River FS Alternatives
April 26, 2016 Sediment GSR Tools Page 10
Remedial Alternative
Dredge Volume (cubic yards)
Dredge Area
(acres)
Cap Area
(acres)
PCB Mass Removal
(kilograms)
Cost Estimate
(US million $)
Construction Time
(Years)
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)
Lower Fox River FS Alternatives
April 26, 2016 Sediment GSR Tools Page 11
Remedial Alternative
Dredge Volume (cubic yards)
Dredge Area
(acres)
Cap Area
(acres)
PCB Mass Removal
(kilograms)
Cost Estimate
(US million $)
Construction Time
(Years)
Alt 1 (Dredge, 500ppb)
776,791 498 0 1,157 118.3 0.9
Alt 2 (Dredge,
1,000 ppb) (Selected)
586,788 328 0 1,111 99.9 0.7
Alt 3 (Cap to max.
extent) 170,858 193 135 764 62.9 1.3
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)
Applied 3 Different Established Tools to the Sites
1) SiteWiseTM(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
April 26, 2016 Sediment GSR Tools Page 12
Model #1: SiteWiseTM Model #2: AECOM Tool
Model #3: AECOM qSRT
GHG (CO2, CH4, N2O) Emissions
Energy NOx Emissions SOx Emissions
PM10 Emissions Landfill
Accident Risk – Fatality
& Injury Lost Hours – Injury
CO2 Emissions CO Emissions
Energy NOx Emissions SOx Emissions
PM10 Emissions Landfill
Ecological Footprint
Accident Risk – Fatality & Injury
Impacts on Air Impacts on Soil Conditions
Impacts on Ground & Surface Water Impacts on Ecology
Use of Natural Resources & Waste
Impacts on Human Health & Safety Ethics & Equality
Neighborhood & Locality Communities &
Community Involvement Uncertainty & Evidence
Direct Economic Costs & Benefits
Indirect Economic Costs & Benefits Employment & Employment Capital 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.
Quantitative and Qualitative Metrics Evaluated
April 26, 2016 Sediment GSR Tools Page 13
Results & Comparative Analysis
Hudson River Superfund Site Results Model #1: SiteWiseTM
April 26, 2016 Sediment GSR Tools Page 15
0%
20%
40%
60%
80%
100%
Impacts of Remedial Alternatives (Normalized to highest impact alternative)
Alt. 1 Cap-3-10-Select Alt. 2 Rem-3-10-Select Alt. 3 Rem-0-0-0 Selected Alternative
Hudson River Superfund Site Results Model #2: AECOM Tool
April 26, 2016 Sediment GSR Tools Page 16
0%
20%
40%
60%
80%
100%
Impacts of Remedial Alternatives (Normalized to highest impact alternative)
Alt. 1 Cap-3/10/Select Alt 2. Rem -3/10/Select Alt. 3 Rem-0/0/0 Selected Alternative
AECOM qSRT (Model #3) – Weight & Rank Each Indicator
Assessment Criteria Weight Remediation Option 1 2 3
Environ-mental
Impacts on Air 2 10 6 2 Impacts on Soil and Ground Conditions 5 15 15 20 Impacts on Groundwater and Surface Water 3 12 9 9 Impacts on Ecology 4 12 12 8 Use of natural Resources and Waste 3 12 6 3
TOTAL 17 61 48 42
Social
Impacts on Human Health and Safety 5 20 15 10 Ethics and Equality 3 6 9 9 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
Economic
Direct Economic Costs and Benefits 2 6 4 2 Indirect Economic Costs and Benefits 2 2 2 4 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
April 26, 2016 Sediment GSR Tools Page 17
Hudson River Superfund Site Results Model #3: AECOM qSRT
April 26, 2016 Sediment GSR Tools Page 18
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
1 2 3 4 5
Wei
ghte
d Sc
ore
(%)
Remedial Option
Percentage of Maximum Score (with Weightings)
Economic Environmental Social Overall
Most Sustainable
Least Sustainable
Selected Alternative
Sustainability Assessments Point to Different Alternatives
Site Selected Alternative
Sustainable Alternative
Implementation Considerations
Hudson River Alternative #2 2,651,730 CY
$413MM
Alternative #1 1,732,820 CY
$338MM
On-site disposal of waste and social (quality of life indicators) were considered but not evaluated in the FS
Lower Fox River (OU3)
Alternative #2 586,788 CY
$99.9MM
Alternative #2 586,788 CY
$99.9MM
Waste was pumped via pipeline as a trucking alternative
Actual construction varied from the alternatives evaluated in FS for a variety factors
Most sustainable alternative determined in this assessment
April 26, 2016 Sediment GSR Tools Page 19
Conclusions & Lessons Learned
1. Sustainability assessments are consistent with Federal and State regulations governing remediation of sediment sites
2. Sustainability tools provide a structured & transparent methodology during remedy evaluation and selection process
• Allows stakeholder considerations of impacts and tradeoffs • Optimizes benefits relative to environmental, social, and economic impacts
• Environmental metrics are more easily quantified than social and economic indicators
3. All 3 tools reached similar conclusions about the most sustainable alternative
• AECOM qSRT requires a more robust stakeholder input to establish meaningful cumulative sustainability rankings and weights
April 26, 2016 Sediment GSR Tools Page 20
Acknowledgments
ExxonMobil General Electric Wisconsin DNR AECOM Staff (Anne Fitzpatrick, Matt Salmon,
Maureen McBride, & Gerlinde Wolf)
Thank you!
Amanda D. McNally, P.E., [email protected]
Frank J. Messina, [email protected]
April 26, 2016