Petroleum Site 14 update to the Moffett Restoration Advisory Board, March 10, 2011, by Wilson Doctor, Navy Project Manager

1. Welcome
Petroleum Site 14 Update
Former Naval Air Station
Moffett Field
M ff Fi ld
Wilson Doctor - Navy Project Manager
3/10/11 RAB meeting

2. Presentation Overview
• Site 14 background
• Recent Site 14 activities
• Site characteristics
• Upcoming cleanup activities
• Site strategy

3. Site 14 Background
• Former Department of Defense motor vehicle gasoline station
• Two former 5,000 gallon underground storage tanks (USTs)
removed in 1986
– Stored unleaded gasoline and diesel fuel
• 1986 to 2006: Navy conducted soil sampling groundwater
sampling,
sampling, and treatability studies
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4. Recent Site 14 Activities
• 2008 to present: Additional sampling to characterize site
• March 2010: Discovered uncharacterized area of petroleum
constituents in groundwater
• June 2010: Conducted groundwater sampling
– Petroleum constituents related to Site 14
• Based on findings, low pressure air sparge treatment system design
was modified to treat this area
– January 31 to March 18, 2011: Install treatment system
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5. Site Characteristics
Extent of TPH-G Extent of Benzene
Concentrations Concentrations in
in Groundwater Groundwater
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6. Air Sparging )
• Inject air into the ground using air sparge
wells and an air compressor
• Injected air increases oxygen levels and
promotes biodegradation of petroleum
constituents in groundwater
• Sparge wells will inject air into sandy water-
bearing layer between 18 and 23 ft bgs to
achieve treatment
• The system is expected to operate for one
year followed by a monitoring period
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7. Well Locations
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8. Site Strategy
Biosparging System Operation
System
S t
Operation/System
Optimization no
Rebound yes
Within Acceptable
Limits?
no
no
Asymptotic
Remediation yes Shut Biosparging System
Conditions Down and Evaluate
Goals Achieved?
Realized? Contaminant Rebound
yes
yes
Implement MNA to Cleanup Goals
Site Closure
Achieve Cleanup Goals Achieved?
no
Monitored Natural Attenuation 8

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10. 10

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12. Thank You
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