Former NAS Moffett Field

Site 25 Remedial Action Update

Bryce Bartelma, PG

Salient Federal Solutions

supporting

Navy BRAC PMO West

November 29, 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

2

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

3

Temporarily Re-routeStorm Water & WATS effluent

4

Catch Basin

Storm WaterSettling Vault

August 2012 Conditions at IR Site 25

5

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 6

Biological Protection Measures

7

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

8

• Planned excavation depths of 0.5 – 1.5feet below ground surface

• Field surveying to verify dig depths

• Grid confirmation sampling

Over-excavations

9

• Several samples confirmed additionalover-excavation was required

• Primarily in Eastern Diked Marsh (EDM)

• Depths of up to 5 feet below groundsurface (EDM) encountered groundwater

IR Site 25 Remedial Action Facts

10

• Excavation depths of 0.5 to 5.0feet below ground surface

• 36,390 cubic yards of sedimentfrom nearly 32 acres

• 19,500 linear feet of biological siltfencing

• Utilized up to 14 biologists

• Bypassed 15,724,800 gallons ofWATS and storm water

• 236 confirmation samples

• 173 days with up to 40 workers(over 23,502 hours) on site

• 2,173 truck loads of sedimenttransported to landfill

Aerial Imagery

11

Aerial Imagery

12

Vegetation Restoration

Pickleweed

Salicornia

virginica

Saltgrass

Distichlis

spicata

13

• All vegetation areas removedduring Remedial Action will berestored (excludes EDM andinundated mud flats)

• Two types of hydroseed palettes(High Salt Marsh and TransitionalUpland) will be used withmajority of seeds includingpickleweed and saltgrass

• Minimum of two years monitoringand maintenance

• Options for irrigation services andadditional hydroseeding/plantings

Schedule

• Sediment Excavations andDisposal

Completed

• Vegetation Restoration

Nov./Dec. 2012

• Vegetation Monitoring

Ongoing

• Submit Remedial ActionCompletion Report

Spring 2013

14

Questions?

15

Point of Contact:

Scott Anderson

BRAC Environmental Coordinator

(619) 532-0938

scott.d.anderson@navy.mil