Presentation to the Moffett Restoration Advisory Board November 18, 2010: Former Orion Park Housing Area (OPHA) Supplemental Site Investigation for Groundwater

1. FORMER ORION PARK HOUSING
AREA (OPHA)AREA (OPHA)
SUPPLEMENTAL SITE INVESTIGATION
FOR GROUNDWATER
Restoration Advisory Board Project Update
November 18, 2010

2. Former OPHA Site

3. Site Use

4. A1 –
TrichloretheneTrichlorethene
(TCE) Plume in
Upper (A1)
ZoneZone

5. A2 –TCEA2 TCE
Plume in Lower
A2 Zone

6. Supplemental Site Investigation (SSI)pp g ( )
 Problem - TCE in upper (A1) zone & lower (A2) zones ofpp ( ) ( )
unconfined aquifer
 Purpose – Assess whether an on-site source of TCE is present at
f O i P k Aformer Orion Park Area
 Focus on 9 locations of concern (LOCs) for TCE
 5 LOCs in AI zone
 4 LOCs in A2 zone
 Drill cone penetrometer/membane interface probes (MIP) at 28 to 50 locations
 Then, push probes for grab groundwater samples at 0 to 18 locations (based on
MIP results), analyze for TCE
 Install 0 to 9 groundwater wells at sources, if any

7. Investigation Areas in Upper (A1) and Lower
(A2) Zones(A2) Zones
Investigation
A i UArea in Upper
A1 Zone
Investigationg
in Lower A2
Zone

8. 5 Locations of
Concern (LOCs) –
Upper A1 Zonepp

9. 4 Locations of Concern (LOCs) –
Lower A2 Zone

10. Membrane Interface Probe (MIP)
 MIP Responsep
 20 readings/foot or 0.05-
foot increments
 P fil VOC t ti i Profiles VOC concentrations in
unsaturated & saturated
zones
 Instantaneous data outputs
 Combined with cone
penetrometer test (CPT)penetrometer test (CPT)
sensors - records lithology

11. Membane Interface Probe (MIP) –
I tImprovements
 Hardware  Software Improvements Hardware
Improvements
 Improved sensor loop
 Software Improvements
 Better correlation of readings
with CPT and MIP profilingp p
inside probe
 Better gas
 Direct feed into Geographic
Information System (mapping
) d lchomatographs
 Follow standard-
ti d
program) and Environmental
Visualization Software (EVS)
(Geology and Groundwateroperating procedures (Geology and Groundwater
modeling tool) for interpretation

12. Example - MIP Profile Indicates Source? - YES
Discrete Sample ResultsMIP Logs
CPT Logs
TCE 1,1-DCE Depth
Discrete Sample ResultsMIP Logs
Capillary fringe
MIP log legend
Baseline (variable)
5.0 e +5
1.0 e +6
5.0 e +6
Maximum response at 10.45 feet
5.0 e 6

13. Example - MIP Profile Indicates Source? – No (Plume)
TCE 1,1-DCE Depth
Discrete Sample Results
Capillary fringe
MIP log legend
Baseline (variable)
5.0 e +5
1.0 e +6
5.0 e +6Initial response at water table
Maximum response at 26.45 feet
p

14. SSI Schedule
Phase Description Dates
Investigation,
Phase 1
Water Level Measurement &
Monitoring Well Sampling
November 2010
Investigation SSI Investigation (CPT/MIP), January & February 2011Investigation,
Phases 2 ,3 & 4
SSI Investigation (CPT/MIP),
Direct-push Investigation,
Monitoring Well
Installation/Development & Sampling
January & February 2011
Investigation,
Phase 5
Investigation –Derived Waste
Management,
Laboratory Analysis
February - June, 2011
Reporting Draft Report for review May 2011
dmy4

15. Slide 14
dmy4 put in table
dayna.yocum, 11/15/2010

16. OPHA Project Team Contactsj
 US Army – Guy Romine – (443) 567-1772 US Army Guy Romine (443) 567 1772
 US Army Corps of Engineers – Cynthia Burris (916)
557-6745557 6745
 US EPA – Alana Lee – (415) 972-3141
 Regional Water Quality Control Board Elizabeth Regional Water Quality Control Board – Elizabeth
Wells (510) 622-2440

17. Questions