Armen Cleaners Indoor Air Quality Investigation. Jon Gulch, OSC U.S. EPA, Region V, ERB

Transcription

1 Armen Cleaners Indoor Air Quality Investigation Jon Gulch, OSC U.S. EPA, Region V, ERB

2 Purpose of Investigation Assist MDCH in Evaluating Indoor Air Quality of Residences for the Presence of VOCs Associated with a Historical Release of PCE from a Dry Cleaning Facility

3 Physical Setting Operating Dry Cleaner Since Early 1950 s s in Residential Neighborhood Historical Releases to Subsurface Shallow Groundwater (<10 feet) Complex Geology (sands, silts, clays)

4 Situation Presumed Source Area Removed in 1980 s Shallow Soil Contamination GW Contaminated Indoor Air Sampling of Neighboring Residences

5 Project Challenges Limited Hydrogeological Data Available Shallow Groundwater Source for Vapor and Groundwater Contamination Still Present Complex Geology

6 Project Challenges (continued) Residences in Close Proximity (20 feet) to Dry Cleaner Armen Cleaners - Still Active

7 Historical Data

8 Historical Data (continued) Indoor Air of Residences Contaminated with VOCs? Background Source(s)? Ambient Air? Subsurface? Understanding of Hydrogeology at the Site? Existing Source Area(s)?

9 Historical Groundwater Flow

10 Goals of Investigation 1)Evaluate for the Presence of VOCs in Ambient Air and in Subsurface Structures

11 Goals of Investigation 2) Evaluate for the Presence of VOCs in Indoor Air of Nearby Residences

12 Goals of Investigation 3) Evaluate for the Presence of VOCs in the Subsurface (Unsaturated Zone)

13 Team Members U.S. EPA Region 5 Emergency Response Branch Grosse Ile, MI U.S. EPA Environmental Response Team (ERT) Edison, New Jersey Superfund Technical Assessment and Response Team (START) Region 5 Tetra Tech EM Inc.

14 Team Members (continued) Local, County, and State Agencies City of Ann Arbor Washtenaw County Department of Environmental Health Regulation Washtenaw County Department of Public Health

15 Team Members (continued) Local, County, and State Agencies (continued) Michigan Department of Environmental Quality Michigan Department of Community Health

16 The Site

17 Study Area 1 to 2 Block Radius Surrounding Armen Cleaners Residential and Subsurface Structures (manholes, utility boxes, etc.) 50 feet x 50 feet Grid Used Approximately Sampling Locations

18

19 Investigation Overview Conduct Utility Survey Interview of Residents/Occupants Identification and Removal of Potential VOC Sources from each Residence Secure Access from Home Owners and Occupants Advance Geoprobe Soil Borings Membrane Interface Probe (MIP)

20 Investigation Overview (continued) Install Soil Gas Probes Based on MIP Data Basement of Residences within Plume Soil Gas Sample Collection and Analysis Indoor Air Sampling-U.S. EPA-ERT ERT TAGA Screen Residences for VOC Sources and Have Any Remaining Removed

21 Investigation Overview (continued) Indoor Air Sampling (continued) Collect and Analyze Air Samples (Summa and Real Time using U.S. EPA-ERT ERT TAGA) Basement Soil Gas Probes Outdoor Air Sampling Exterior of Residences Underground Structures Plot Data

22 Investigation Overview (continued) Scope Allowed a Unique Snapshot of the Full Vapor Intrusion Pathway Soil/GW to Soil Vapor to Sub-slab to Indoor Air to Ambient Air Use of Real-Time Data Collection Techniques and Triad Approach Results Driven

23 Resident/Occupant Interviews Door to Door Interviews and/or at a Public Meeting Standardized Form Help Identify Background VOC Sources Direct Occupants to Remove any Potential Sources of VOCs

24 Access Agreements Door to Door Interviews and/or at a Public Meeting Locate Utilities/Underground Structures on Private Property Answer Questions About Upcoming Field Work Combined with Occupant Interviews

25 Soil Borings - Direct Push Methodology Begin at Source Dry Cleaner Membrane Interface Probe (MIP) Define Vertical and Horizontal Limits of Plume Conducted Prior to U.S. EPA-ERT ERT TAGA Unit On-Site

26 Membrane Interphase Probe

27 MIP Continuous Real-Time Vertical Profiling of Subsurface Identify Extent of Plume Including Zones of Contamination and Migration Pathways Data Utilized to Generate 3-D 3 D Maps Assist in Determining Soil Gas Probe Locations and Depths

28 MIP Advancement

29 Soil Gas Probe Installation Semi-Permanent; i.e. MDEQ will Utilize Soil Gas Probes During Subsequent Remedial Activities Locations Based on MIP Data Allow Monitoring of Contaminant Plume and Quantification of Soil Gas Concentrations

30 Soil Gas Probe Installation (continued) Assist in Evaluation of Indoor Air Intrusion Pathways Installed by Hand

31 Soil Gas Probe

32 Collection of Soil Gas Samples Samples Collected by START Using Tedlar Bags Analyzed in the Field Using U.S. EPA- ERT TAGA Unit Data Plotted on GIS Data Base as it is Generated

33 Sampling of Soil Gas Probes

34 Trace Atmospheric Gas Analyzer (TAGA)

35 U.S. EPA-ERT TAGA

36 Indoor Air Sampling Screen House Using U.S. EPA-ERT ERT TAGA Summa Canisters - (24-Hour) 2 Per Residence Basement Probes (sub-slab) slab) only those houses within plume

37 SUMMA Canister Sampling

38 Outdoor Air Ambient Air SUMMA Canisters and TAGA Adjacent to Houses Basement First Floor

39 SUMMA Canister Sampling

40 TAGA Sampling

41 Plot Data Surveyed Using Global Positioning System (GPS) U.S. EPA and Previous Data (MDEQ) will be Included Real-time Updates on Database During Investigation

42 Plot Data (continued) Plotted Using Geographic Information System ArcMap Final Database Provided to Task Force Members in Electronic Form

43 Final Report Site Has Been Selected by TIO as a Case Study Detailed Report is Currently Being Developed MDCH is Preparing a Health Consultation for the Site Final GIS Database Will Include all of Data Collected to Date Includes (Analytical, GPS, MIP, TAGA)

44 Preliminary Findings Source Area Still Believed to be Present in Subsurface Around Dry Cleaners PCE in Excess of Soil Saturation Concentration Believed to be Present Good Correlation of MIP Data to Soil Vapor Concentrations

45 Armen Cleaners - CSM

46 MIP Log - Source

47 ECD Detector

48 PID Detector

49 Soil Vapor Plume

50 Ambient Air Results

51 Results Summary

52 Preliminary Findings (continued) PCE Identified in Indoor Air of the Houses Around Dry Cleaner Background VOCs Still Detected in Indoor Air Samples

53 Background VOCs Acetone ( ppbv) Ethanol ( ppbv) 2-propanol ( ppbv) Freon 11 (1.1 ppbv) Freon 12 (0.68 ppbv) Chloromethane (0.91 ppbv) Methylene Chloride (0.9 ppbv)

54 Background VOCs (continued) Toluene ( ppbv) M,p Xylene ( ppbv) 2 Butanone (3.9 6 ppbv)

55 Status of the Project Field Work Completed Case Study Report Draft to be Completed November 2004 (draft) Data Entered into GIS Database Final Products Anticipated to be Completed Fall 2004 EPA - TIO (BTSC) Web Site Will Have Electronic Version of report

56 Additional Information Jon Gulch - U.S. EPA gulch.jon jon@epa.gov David Sawicki Tetra Tech EM Inc david.sawicki sawicki@ttemi.com

57 Questions?