moffett rab site 25 update
DESCRIPTION
Update on Site 25 stormwater retention pond clean-up by Bryce Bartelma at the August 9, 2012, meeting of the Moffett Restoration Advisory Board.TRANSCRIPT
Former NAS Moffett Field
Site 25 Remedial Action Update
Bryce Bartelma, PG
Navy BRAC PMO West
August 9, 2012
RAB Meeting
IR Site 25
IR Site 25 encompasses approximately 230 acres and was constructed for useas part of the Moffett Field storm water management system since 1953
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The Navy is coordinating remedial action activities with NASA as theyprepare to conduct their cleanup activities at Area of Investigation (AOI)-14
AOI-14
Remedial Design andRemedial Action Work Plan
• Final Remedial Designand Remedial ActionWork Plan (RD/RAWP)distributed on March 30
• Removal of over 32,500cubic yards of sedimentfrom nearly 32 acres
• Planned excavationdepths of 0.5 – 1.5 feetbelow ground surface
• Restore vegetatedareas with pickleweedand other native grass
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April 2012 Conditions at IR Site 25
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Step 1: Temporarily Re-routeStorm Water & WATS effluent
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Catch Basin
Storm WaterSettling Vault
August 2012 Conditions at IR Site 25
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August 2012 Conditions at IR Site 25
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Step 2: Additional Water Management?
• No immediate plans to coffer dam the site if weather stays dry
• Water table just beneath ground surface
• Working with USFWS to potentially lower water table locally inponds adjacent to site
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Balancing the Water Table
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Biological Observations at Site 25
NESTING
• Alameda Song Sparrow
• Western Harrier
• Mockingbird, marsh wren, bushtit andkilldeer
OBSERVED
• Harvest Mice (unidentified subspecies)
• Deer Mice & Voles
• California Least Tern (in flight)
• Black Rail (vocalizing)
• Fox, jackrabbit, and gopher snake
NOT OBSERVED
• Western Pond Turtle (WPT)
• Western Snowy Plover
• California Clapper Rail 10
Biological Protection Measures
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PROTECTION MEASURES
1. Visually inspect/clear vegetationprior to removal
2. Hand remove pickleweed
3. Silt fencing along access pointsand suitable habitat areas
4. Continuous biologicalmonitoring
5. Coordination with CDFG andUSFWS
Sediment Excavations
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• Planned excavation depths of 0.5 – 1.5feet below ground surface
• Field verification for dig depth
• Grid confirmation sampling
Vegetation Restoration
Pickleweed
Salicornia
virginica
Saltgrass
Distichlis
spicata
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• All vegetation areas removedduring Remedial Action will berestored (excludes EDM andinundated mud flats)
• Two main types of vegetation
• Minimum of two years monitoringand maintenance
• Options for irrigation services andadditional plantings
Schedule
• Vegetation Removal Prep
Nearing Completion
• Biological Surveys andSediment Excavations
Ongoing
• Vegetation Restoration
Fall 2012
• Submit Remedial ActionCompletion Report
Spring 2013
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Questions?
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Point of Contact:
Scott Anderson
BRAC Environmental Coordinator
(619) 532-0938