motorola 52 nd street superfund site – update

Motorola 52nd Street Superfund Site – Update

U.S. Environmental Protection AgencyRegion IX

April 2014

April 2014 U.S. Environmental Protection Agency

Outline

• EPA staff update:•Martin Zeleznik has retired•Rachel Loftin (OU1, OU2) & Community

Involvement (Amanda) not here tonight• Introduction to the project (brief)• Update on EPA investigation activities

during February•TAGA Truck

2April 2014 U.S. Environmental Protection Agency

Motorola 52nd Street Superfund Site – Overview


April 2014

April 2014

U.S. Environmental Protection Agency

Groundwater Contamination


Responsible PartiesElectronics & aeronautical manufacturing:

• Motorola – former manufacturing facility at 52nd Street & McDowell• now Freescale

• Honeywell – existing facility at 34th Street and Air Lane at northern boundary of airport

• Number of smaller facilities• Joray/Kachina


Contamination

• Solvents used to clean electronic components (circuit boards, etc.) and aircraft parts (“Degreasing”)

• Spills, leaks & disposal to ground lead to contamination of soil & groundwater underneath facilities

• Groundwater contamination has moved off-site


Primary Contaminant - TCE


Trichloroethylene (TCE)• Chlorinated solvent used in electronics

production and aerospace industry• Formerly present in many commercial

products (“Liquid Paper”) & still in a few (e.g., gun-cleaner, WD-40)

• Contaminant of Concern at Motorola 52nd Street Superfund site (and at many other Superfund sites)

Groundwater TCE Plume


OU1 (on 52nd St. facility) pump and

treat plantOU2 (corner 20th &

Washington) pump and treat plant

Both treatment plants send the treated water to beneficial use, such as manufacturing processes or irrigation

Treatment plants

September 2008

Reductions in TCE plume

Motorola 52nd Street Superfund Site – Vapor Intrusion Investigation Using

EPA’s TAGA Truck(Trace Atmospheric Gas Analyzer)


April 2014

April 2014 U.S. Environmental Protection Agency

Vapor Intrusion (VI)

121/15/2014 U.S. Environmental Protection Agency

• Vapors from soil and/or groundwater contamination can migrate upwards into buildings

• Potential indoor air exposures

• Chlorinated solvents (TCE)

Multiple Lines of Evidence


GWContam

Soil Vapor

Indoor Air

Gradient

Vapor Intrusion?

•Outdoor air

•Indoor air

•Sub-slab

•Soil gas

•Groundwater

5’

15’

The TAGA Truck


OU1


Subsurface bedrock ridge – promote TCE concentration and vapor intrusion?

OU1 Vapor Intrusion Study


McDowellNorthside

McDowellSouthside

Lindon ParkSchools

TAGA at OU1 - 2014


2 Goals: •Confirmation indoor air sampling in a few homes

• sub-slab mitigation systems working correctly?

•Additional soil gas sampling near some homes with previously elevated indoor air TCE concentrations•Sampling occurred in Lindon Park & both McDowell areas (Northside and Southside)

TAGA Findings


Summary of Findings & Actions from TAGA 2014

• Indoor air sampled – 6 residences: – Where detected, TCE within protective

risk range– Upgraded sub-slab depressurization

(SSD) systems are functioning very well• Soil Gas Probes – 5 locations

– TAGA data confirms previous data– No evidence of another localized source

OU2 – Vapor Intrusion

19U.S. Environmental Protection Agency

Subsurface bedrock ridge – promote TCE concentration and vapor intrusion?

OU2 Schools & Homes


GW well with high TCE concentrations.

School

School

Phased Approach• Installed soil gas probes one

week prior to TAGA Truck arrival– Saved time and put TAGA truck

capabilities immediately to use– Limited probes (blue circles)

initially; added step-outs as needed

• Established EPA Action Levels prior to going out into field

– If soil gas data indicated potential Hazard Index greater than 3, sampled indoor air immediately

• EPA with TAGA Truck was able to get soil gas data, obtain access agreement from resident, and tested indoor air in home within a single day (3 homes)

2 more step-outs

OU2 Results & Lessons Learned


• TCE concentrations in some of the initial soil gas samples above screening level:– all soil gas locations drilled & sampled (step-outs)

• TCE concentrations in 3 of 33 soil gas samples above screening level for Hazard Index= 3 – Prompted indoor air testing in 3 homes– Indoor air was non-detect or trace (indoor source?)

• Using the TAGA Truck allowed more rapid assessment of soil gas and, where needed, indoor air – allowed decisions in the field

OU3


M52 OU3: Overview


• The OU3 Working Group (APS and Honeywell) are working on a RI/FS which likely lead to a final ROD

• Soil Gas monitoring in three locations is required as part of the RI investigative work

• Soil Gas concentrations at one soils gas well was elevated relative to the other two wells prompting two questions: – Is there a vapor intrusion risk at the surface?– Are the soil gas concentrations at SVMW-1 from

groundwater or an unknown source?

M52 OU3: Locations of Soil

Gas Wells

SVM-2

SVM-1

SVM-3

TitleHeading:

• bullet• bullet


OU3: TAGA Soil Gas Data

• No vapor intrusion risk was found in the area around the SVM-1

• EPA is investigating possible causes of the elevated soil gas concentrations in the vicinity of SVM-1

• Results from the investigation will be used to determine future actions

• The area around SVM-1 is the only OU3 soil gas issue discovered. Most work in OU3 is focused on the state of VOCs in groundwater (i.e. RI/FS)

OU3 Results and Next Steps

TAGA Truck Field Work

Photo Sequence of EPA Doing Field Work

Drilling Soil Gas Probes in Right-of-Way

Installing Soil Gas Probes (15 feet below ground surface)

Retrieving Soil Gas Probe

Collection & Analysis of Soil Gas

If soil gas results showed potential indoor air TCE greater than HI=3, use “sniffer”

in TAGA Truck and enter building

TAGA Machine measures real time data

Questions or Comments?

motorola 52 nd street superfund site – update

Documents

street superfund site

ou1 vapor intrusion

tce plumemotorola

manufacturing facility

air lane

facility pump

additional soil gas

retiredrachel loftin