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Moffett Groundwater UpdateMay 15, 2008

Julie Crosby-BrooksRemedial Project Manager

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Presentation OverviewPresentation Overview

• Base-wide Groundwater Monitoring – Water Level Measurements– Groundwater Sampling

• Site 28– WATS Overview– Coordination with MEW Companies and NASA– Path Forward

• Site 26– EATS Overview– EATS Technical Memorandum– Path Forward

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Introduction Introduction –– Regional Regional Location MapLocation Map

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Introduction Introduction –– Plan View of Plan View of Regional PlumeRegional Plume

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Moffett AquifersMoffett Aquifers

Approximate Depths of Moffett Aquifers

• Upper A-Aquifer: 0 - 35 Feet Below Ground Surface (BGS)

• Lower A-Aquifer: 35 – 55 Feet BGS

• B Aquifer: 55 – 160 Feet BGS

• C Aquifer: 160 – 240 Feet BGS

• Deep Aquifer: Greater than 240 Feet BGS

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Introduction Introduction –– AquifersAquifers

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Basewide GW Program Basewide GW Program ––Groundwater ElevationsGroundwater Elevations

Groundwater Elevation Measurements• Joint Effort with Middlefield-Ellis-Whisman (MEW) Companies and NASA• Water Levels Measured in March and November • Results are Compiled and Evaluated in Annual Groundwater Reports

– 2007 Annual Groundwater Report Available in June 2008• Upper and Lower A-Aquifer Wells and B-Aquifer Wells

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One Day Event – Twice a Year

1000+ Total Water Level Measurements

400+ Water Level MeasurementsCollected by Navy

Approximately 20 Navy Field Crews

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Basewide GW Program Basewide GW Program ––2006 Water Levels2006 Water Levels

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Basewide GW Program Basewide GW Program ––Groundwater SamplingGroundwater Sampling

Groundwater Sampling • Joint Effort with MEW Companies and NASA • Sampling Conducted in November / December Timeframe • Results are Compiled and Evaluated in Annual Groundwater Reports

– 2007 Annual Groundwater Report Available in June 2008• Upper and Lower A-Aquifer Wells and B-Aquifer Wells_______________________600+ Wells Sampled North of

Highway 101

Navy Samples Approximately 125 of the Wells

Volatile Organic Compounds (VOCs)

Dissolved Metals & Total Petroleum Hydrocarbons (TPH) - Every 5

Years

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Basewide GW Program Basewide GW Program –– 2006 2006 Annual Report ConclusionsAnnual Report Conclusions

Site 28 - WATS• Groundwater Consistently Flows to the North• Dissolved VOCs Continue to Flow onto Moffett

Site 26 - EATS• Groundwater Consistently Flows to the North• VOC Plume Stable – No Movement or Shape Change

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Site 28 Site 28 –– IntroductionIntroduction

Site 28 - Introduction

• Located West of the Runways

• Contamination is from Navy Sources and Regional Plume

• Includes West-Side Aquifers Treatment System – WATS

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Site 28 Site 28 –– WATS WellsWATS Wells

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Site 28 Site 28 –– WATS OverviewWATS Overview

WATS is a Groundwater Pump and Treat System

• Began Operating in 1998 • Complies with Requirements in the MEW Study Area Record of Decision

(ROD)– MEW ROD Finalized in 1989– Navy Adopted MEW ROD in 1993

• Six Upper A-aquifer and Three Lower A-aquifer Extraction Wells• Treats Groundwater Using Advanced Oxidation Process and Granular

Activated Carbon• Treated Water is Discharged to the Eastern Diked Marsh and Stormwater

Retention Pond (Northern Moffett Boundary)– Discharged per the Requirements of the National Pollutant Discharge

Elimination System (NPDES) Permit– All Discharge Water has been Compliant with NPDES Requirements

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Site 28 Site 28 –– WATSWATS

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Site 28 Site 28 –– WATS Operation DataWATS Operation Data

2007 Operation Data

• WATS Operational 98.9% of Time• Treated 34,532,488 Gallons of Extracted Groundwater• Removed 378 Pounds VOCs• Annual O&M cost is approx $760,644 or $2,012/pound

Lifetime Operation Data

• Treated 304,302,868 Gallons of Extracted Groundwater

• Removed 3,997 Pounds VOCs

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Site 28 Site 28 –– Coordination with Coordination with MEW CompaniesMEW Companies

Currently Partnering with MEW Companies to Prepare Site-wide Focused Feasibility Study (FFS) and Technical Impracticability (TI) Evaluation

• Evaluates Effectiveness of the Current Remedy• Evaluates and Compares Alternatives for Site-Wide Groundwater Cleanup

Submitted Volume I (Sections 1 through 5) to EPA on April 14, 2008

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Site 26 Site 26 –– IntroductionIntroduction

Site 26 - Introduction• Located East of the Runways• Contamination is from Navy Sources Only (Not Part of Regional Plume)• Includes East-Side Aquifer Treatment System – EATS

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Site 26 Site 26 –– EATS Overview & EATS Overview & Operation DataOperation Data

East-Side Aquifer Treatment System - EATS• Operated from January 1999 Through July 2003• Five Upper A-Aquifer Extraction Wells • Treats Groundwater Using an Air Stripper and Granular Activated Carbon

EATS Lifetime Operation Data• Removed 67 Million Gallons of Groundwater• Approximately 23.6 Pounds VOCs

EATS Taken Off-Line in 2003 to Evaluate:• Plume Stability• Chemical of Concern Rebound• Natural Attenuation• Application of Hydrogen Release Compound® (HRC)

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Site 26 Site 26 –– EATSEATS

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Site 26 Draft Technical Site 26 Draft Technical MemorandumMemorandum

• Reviewed Site Hydrogeology

• In Depth Evaluation of Contamination

• Evaluation of Remedial Alternatives

Sand Thickness Evaluation

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Site 26 Draft Tech Memo Site 26 Draft Tech Memo ––Hydrogeology EvaluationHydrogeology Evaluation

In Depth Evaluation of Contamination

• Low Concentration • Plume Contracts with Depth• Residual Limited Contamination Remains in Fine-

Grained Soils

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Site 26 Draft Tech Memo Site 26 Draft Tech Memo –– Remedial Remedial AlternativesAlternatives

Evaluated for Implementabilty and Effectiveness

Optimized Pump and Treat System

Air Sparging / Soil Vapor Extraction

Dual Phase Extraction

Substrate Enhanced Biostimulation

Bioaugmentation

Micro-Scale Zero Valent Iron –Nanoscale Zero Valent Iron

Combination of Biotic and Abiotic Treatment

Phytoremediation

Monitored Natural Attenuation

In-Situ Chemical Oxidation

In-Situ Thermal Treatment

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Site 26 Draft Tech Memo Site 26 Draft Tech Memo –– Remedial Remedial AlternativesAlternatives

Remedial Alternatives that are Effective and Implementable Screened Out Based on Cost

Micro-Scale Zero Valent Iron – $40 Million

Nanoscale Zero Valent Iron - $46 Million

Combination of Biotic and Abiotic Treatment - $13 to $14 Million

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Site 26 Draft Tech MemoSite 26 Draft Tech Memo

Site 26 Technical Memorandum Conclusions• No Remedial Alternative can be Implemented Without Inordinate Costs

– Complex Site Hydrogeology • Recommend Evaluating Technical Impracticability Waiver

Navy Will Coordinate with Regulatory Agencies to Develop Path Forward

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Summary Summary –– Moffett Moffett Groundwater ProgramGroundwater Program

Moffett Groundwater Program Path Forward

• Continue Groundwater Sampling and Water Level Measurements– Next Groundwater Sampling Occurs in November / December 2008

• Continue to Operate Pump and Treat System at WATS• Continue Working with MEW Companies to Finalize FFS• Work with Regulatory Agencies to Determine Path Forward at EATS

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Questions