Navy presentation to the Moffett Field Restoration Advisory Board on May 15, 2008, regarding the groundwater clean-up at the East- and West-Side Acquifer Treatment Systems (EATS and WATS).
7. Basewide GW Program –
Groundwater 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
________________________
One Day Event – Twice a Year
1000+ Total Water Level
Measurements
400+ Water Level Measurements
Collected by Navy
Approximately 20 Navy Field
Crews
_______________________
7
9. Basewide GW Program –
Groundwater 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
_______________________ 9
10. Basewide GW Program – 2006
Annual 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
10
11. Site 28 – Introduction
Site 28 - Introduction
• Located West of the
Runways
• Contamination is from Navy
Sources and Regional Plume
• Includes West-Side Aquifers
Treatment System – WATS
11
13. Site 28 – WATS 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
13
15. Site 28 – WATS 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
15
16. Site 28 – Coordination with
MEW 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
16
17. Site 26 – Introduction
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
17
18. Site 26 – EATS Overview &
Operation 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)
18
20. Site 26 Draft Technical
Memorandum
• Reviewed Site Hydrogeology
• In Depth Evaluation of
Contamination
• Evaluation of Remedial
Alternatives
Sand Thickness Evaluation
20
21. Site 26 Draft Tech Memo –
Hydrogeology Evaluation
In Depth Evaluation of Contamination
• Low Concentration
• Plume Contracts with Depth
• Residual Limited Contamination Remains in Fine-
Grained Soils
21
22. Site 26 Draft Tech Memo – Remedial
Alternatives
Evaluated for Implementabilty and Effectiveness
Optimized Pump and Treat System Combination of Biotic and Abiotic
Treatment
Air Sparging / Soil Vapor Extraction
Phytoremediation
Dual Phase Extraction
Monitored Natural Attenuation
Substrate Enhanced Biostimulation
In-Situ Chemical Oxidation
Bioaugmentation
In-Situ Thermal Treatment
Micro-Scale Zero Valent Iron –
Nanoscale Zero Valent Iron
22
23. Site 26 Draft Tech Memo – Remedial
Alternatives
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
23
24. Site 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
24
25. Summary – Moffett
Groundwater 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
25