REMEDY OPTIMIZATION OVERVIEW

Transcription

1 REMEDY OPTIMIZATION OVERVIEW GEORGIA ENVIRONMENTAL CONFERENCE

2 THE CHALLENGE Given an often complex set of site conditions, environmental media and contaminant composition, we are challenged to select remedies that Are protective of human health and the environment Remain protective over time while enabling site reuse Limit future liabilities and/or increase land value Are cost effective Achieve closure

3 THE CHALLENGE Given an often complex set of site conditions, environmental media and contaminant composition, we are challenged to select remedies that Are protective of human health and the environment Remain protective over time while enabling site reuse Limit future liabilities and/or increase land value Are cost effective Achieve closure >>> SITE EXIT?

4 INTRODUCTION Optimization = Quicker and Cheaper (with Equivalent or Improved Protectiveness) Preparing for site closeout and optimization begins at SI Optimization should be a consideration throughout a project life Definition of optimization: an act, process, or methodology of making something (as a design, system, or decision) as fully perfect, functional, or effective as possible Merriam Webster Successful Optimization Requires Realistic characterization of site risks Clearly defined objectives performance targets and final cleanup goals; total cost versus cash flow Understanding of typical remediation system performance Planning for change 4

5 INTRODUCTION Optimization = Quicker and Cheaper (with Equivalent or Improved Protectiveness) Preparing for site closeout and optimization begins at SI Definition of purgatory: a place or state of suffering Merriam Webster Optimization should be a consideration throughout a project life Successful Optimization Requires Realistic characterization of site risks Clearly defined objectives performance targets and final cleanup goals; total cost versus cash flow Understanding of typical remediation system performance Planning for change 5

6 REMEDY OPTIMIZATION OVERVIEW

7 REMEDY OPTIMIZATION OVERVIEW OPTIMIZATION THROUGHOUT REMEDY PROGRAM Optimizing SI, Remedy Evaluation, Selection, and Design Optimizing Remedial Action Operation Optimizing Groundwater Monitoring Conceptual Site Model Reassess CSM and RAOs Review of CSM, RAOs and goals of the monitoring program Risk Assessment Evaluate Remediation Effectiveness Review/refine monitor locations Remedial Action Objectives Evaluate Cost Efficiency Review/refine monitoring frequency Target Treatment Zones Identify Remediation Alternatives Review/refine contaminants to monitor Treatment Train Develop & Prioritize Optimization Strategies Review sampling methods Performance Objectives Implement Optimization Strategy Data evaluation Optimization & Exit Strategy Ensure Regulatory Acceptance

8 INTEGRATING RISK ASSESSMENT SUPPORTING EFFECTIVE DECISION MAKING Phase 2, PA/SI Enough data? RI Remedy needed? FS Remedy type? RD/RA-C/O Site Closeout Remedy & post-remedy risk assessment Remedy complete? Streamline site characterization Determine need for remedy Develop cleanup goals and treatment levels Select appropriate remedy Modify previously selected remedy Provide basis for risk management decisions

9 INTEGRATING RISK ASSESSMENT APPLYING RISK ASSESSMENT FOR RISK MANAGEMENT Remedy Decisions (CERCLA and RCRA) How clean is clean enough? Does cleanup mean contaminant treatment/removal? No further action Remediation necessary Containment Preferred Treatment Preferred Acceptable Risk Low-Level Threat Principal Threat Cumulative cancer risk Noncancer hazard index Reference: OSWER Directive and USEPA (1997) Rules of Thumb for Superfund Remedy Selection [540- R ]

10 EXAMPLE RISK MANAGEMENT & OPTIMIZING LAND USE Apply appropriate USEPA risk management policy Ø Resulted in savings of over $5 million Define minimum remediation for continued industrial use Ø Resulted in savings of over $6 million Tailor site-specific risk assessment to allow alternate site reuse 1. Assess mixed land use options to optimize land use for future redevelopment 2. Account for realistic assumptions regarding exposure Ø Identified savings of over $3 million

11 INTEGRATING RISK ASSESSMENT BALANCING RISK / BENEFIT Why Consider Tradeoffs? Concentration/Risk High Risk Areas Risk Range Low-end Criterion Larger Reduction in Risk Smaller Reduction in Risk Lower % Higher % Marginal Risks/ Uncertainty Effort/Cost ($) 11

12 EXAMPLE BALANCING RISK REDUCTION AND COST Figure Cost Increase Factor Relative to Alternative E-01 Cost Increase Factor Relative to Alternative Hypothetical Post-Remedy Cancer Risk Hypothetical Post-Remedy Cancer Risk - Inhalation Only 1.00E E E E E-06 Residual Cancer Risk E-07 Remedial Alternative

13 INTEGRATING RISK ASSESSMENT USE OF NET ENVIRONMENTAL BENEFIT ANALYSIS Goal: Identify remedies that are ecologically protective, serves the public interest, meets stakeholder goals, help conserve resources that provide human and ecological value, and are generally more cost effective Shifts focus from a chemical-centric view of the environment to environmental services, productivity, and health Quantitative assessment of total impacts related to the remedial alternatives being considered; for example direct and indirect sources of GHGs and relative scale of the GHGs, material reused on site or disposed, travel required to maintain the remedy. Differentiate between remedies that offer equivalent public health and environmental protection using relevant and readily calculable metrics

14 EXAMPLE NET ENVIRONMENTAL BENEFIT Offsite Migra;on Risk Total Energy (MMBTU) Total SOx (tons) Total NOx (tons) CO2e (tons) Fatality Risk Injury Risk Forest Habitat Lost (dsays) Cost $ millions Preferred Alternative? Baseline Alt 1 Alt 2 Alt 3 Alt 4 $2.8 $3.3 $3.6 $4.0 14

15 SETTING REMEDY OBJECTIVES Typical Remedy Selection Criteria Protective Effective Implementable Minimizing cost Regulatory acceptance Community acceptance Alternative Goals & Objectives Reduction of overall contaminant concentrations compared to baseline levels (e.g., >90% reduction) Mass removal to asymptotic levels (following appropriate optimization of the system) Operate only as long as cost-effective Rapid site exit Minimize cash flow Cumulative Cost (in thousands) Monitoring may or may not be required during this period depending on concentrations detected in previous sampling events Year Alternative 1 Alternative 2 Alternative 3

16 UNDERSTANDING TYPICAL REMEDIATION PERFORMANCE Mass Removal Rate (m/t) Conventional Design Level Life-Cycle Design Level Characteristic Curve Extended Maximum Efficiency Exit Point Time (t) 16

17 EXAMPLE PUMP & TREAT OPTIMIZATION CVOC plume in stratified aquifer EPA ROD required extraction of 3 pore volumes in 30 years 3 mile discharge pipeline required OPTIMIZATION OBJECTIVES Estim ated % of Total Mass Removed in 30 Years (Assumes No Biodegradation) Percentage fo Total Mass Removed in 30 years NEW JERSEY SUPERFUND SITE Maximize mass removal Pumping Rate (gpm) Minimize cross-boundary capture Pump-and-Treat System Costs Reduce treatment capacity Achieve EPA s 3 pore volume requirement $25.00 Cost ($MM) $20.00 $15.00 $10.00 $5.00 $ Outcome: 270Approved design O&M -- 30yr Flow Rate (gpm) Eliminated major construction Total Cap Costs elements OPTIMIZATION & SITE EXIT STRATEGIES Est. savings REMEDY >$10M over 30AUGUST yrs25, 2016

18 EXAMPLE TREATMENT TRAIN APPROACH Free Product Recovery Vacuum-Enhanced Product Recovery Air Sparging/Soil Vapor Extraction Pilot Test Ozone Sparging/SVE Phase I Ozone Sparging/SVE Phase II Monitored Natural Attenuation

19 SUMMARY Optimization of a remedy should be continuous throughout remedy evaluation, implementation and post-remedy monitoring Risk analysis throughout project will lead to more efficient investigation and remedy selection Ø The costs of remedies selected need to be warranted by the benefits derived -- Higher cost does not always mean overall lower risk Projects can be expedited by making decisions in the field (as much as possible) using real-time data. Ø New technologies are available for improved access to environmental media for sample collection, as well as analysis of in situ conditions (i.e. contaminant concentrations, lithologic conditions, etc.) Recognize current technological limitations in remedy selection decisions, while being open to innovative technologies where appropriate Ø Multiple remediation technologies Treatment Trains should be used concurrently or sequentially (depending on site-specific conditions) to achieve remedial objectives

20 THANK YOU! Mark Nielsen