1. EPA Vapor Intrusion Update
Former NAS Moffett Field
Restoration Advisory Board Meeting
May 10, 2012
Alana Lee
EPA Region 9
Lee.Alana@epa.gov

2. Vapor Intrusion Study Area – Moffett Field Area and MEW Area

3. Estimated Extent of Regional TCE Shallow Groundwater
Plume

4. Vapor Intrusion
Study Area –
Moffett Field Area
4

5. Sampling Status of “Unsampled” Buildings -
Moffett Field Area - North of Highway 101
13 Currently Occupied Buildings 6 Currently Occupied
Sampled by MEW Buildings Sampled by NASA
– Nov 2011
23 569
N144
48 583A
N212
146 583B
154 583C N213
503 596 N240
543 944 N245
554 T20G
MEW Building –Specific Indoor Air Sampling Reports – Sept 13, 2011
5

6. Vapor Intrusion
Study Area –
Navy & NASA
Buildings
6

7. Sampling Status of Navy Buildings
Navy Indoor Air Sampling Work Plan for Vapor Intrusion – May 2012
22 Buildings to Be Sampled by Navy – May 2012
2 45 567
3 67 N210
10* 76 N239
12 107 N239A
13 126 N243
14 510 N243A
16 555
29 566
7

8. Building 10 Tunnel and Manhole Locations
8

9. EPA TCE Regional Screening Levels and MEW/Moffett Field
Site-specific Cleanup Levels for Chronic Exposure
EPA Regional Screening Level MEW/Moffett Field
(RSL) – December 2011 Cleanup Levels
AIR Cancer Non- INDOOR AIR
(mg/m3) (1x 10-6) cancer (mg/m3)
Residential 0.4 2 1
(24-hr)
Commercial 3 9 ------
(8-hr)
Commercial 2 7 5
(10-hr)
TAP WATER (mg/L) GROUNDWATER
Residential 0.4 mg/L 3 mg/L 5 mg/L
(MCL)
9

10. For More Information - Websites
NASA:
environment.arc.nasa.gov/reports/vapor.html
environment.arc.nasa.gov/maps/vapor.html
EPA:
www.epa.gov/region9/moffettfield
www.epa.gov/region9/mew
www.epa.gov/oswer/vaporintrusion/
For more information on TCE: http:/www.epa.gov/IRIS
and click on TCE link