DuPont Barksdale and Chequamegon Projects Update July 22, 2008 DuPont CRG

July 22, 2008Former DuPont Barksdale Works2 Purpose of Meeting Barksdale: Provide a status update on site priorities and public commitments. Provide a summary of on-going 2008 site activities. Chequamegon-Nicolet National Forest: Provide a status update on site investigation activities at the Cabin Lake and Clover sites.

Former DuPont Barksdale Works Project Update

July 22, 2008Former DuPont Barksdale Works4 Project Priorities Current Priorities:  Identify priority source areas and take appropriate action.  Evaluate for potential off-site surface water issues and take appropriate action. Priorities Addressed: Continue to provide drinking water that meets appropriate Wisconsin regulatory standards for all site-related compounds to residents with impacted wells. Develop plan for long-term drinking water supply and implement as appropriate. Fulfill commitments on Home Value Protection Plan.

July 22, 2008Former DuPont Barksdale Works5 Project Priorities Other Commitments: Continue to work with WDNR in the investigation/cleanup of site- related impacts. Continue to be available and communicate with neighbors.

Summary of 2008 Barksdale Work

July 22, 2008Former DuPont Barksdale Works7 Continue to fulfill water supply commitments Site Investigation Site clearing. Grid sampling of 200 locations. Biased sampling at 300 plus locations. Geophysical work to determine subsurface anomalies. Using explosive detection device (FIDO). Summary of 2008 Work

July 22, 2008Former DuPont Barksdale Works8 map of 08 inv priorities.

July 22, 2008Former DuPont Barksdale Works9 Recovery and Disposal of Residual Site Materials: Removed approximately 800 pounds of DNT. TNT recovery and disposal planned. Evaluation of Remedial Technologies: Field scale bio-pilot being conducted. Continued laboratory studies at GA Tech. University of Waterloo DNX studies. Synthesis of DNX isomers: Completed in early Developing screening values. Summary of 2008 Work

July 22, 2008Former DuPont Barksdale Works10 Alternative Water Supply Waterline Completed December Provides Municipal Drinking Water Access to: 47 Homes 8 Undeveloped Parcels Over 6 million gallons of water delivered through the pipeline since installation.

July 22, 2008Former DuPont Barksdale Works11 Clearing Work Sites

July 22, 2008Former DuPont Barksdale Works12 Residual Product Removal DNT Removal: Discovered solid DNT below a floor slab during Bio Cell preparation at former Trivelene Sweating House.

July 22, 2008Former DuPont Barksdale Works13 Screening with Geophysics (EM61)

July 22, 2008Former DuPont Barksdale Works14 FIDO Analysis Equipment

July 22, 2008Former DuPont Barksdale Works15 Screening with Vacuum Cartridges MEVA SAMPLING PROCESS Clear brush and ground cover. Survey 1-acre grid corners and stake 1/16 th acre sub-squares. Vacuum the surface of each sub-square and record conditions during collection. Return the cartridge to the testing office, incubate the cartridge and analyze with the FIDO detector.

July 22, 2008Former DuPont Barksdale Works16 Sample MEVA results

July 22, 2008Former DuPont Barksdale Works17 TNT Located by MEVA TNT found by FIDO visible only after tall grass & sheet metal hiding it was removed.

Evaluation of Remedial Technologies

July 22, 2008Former DuPont Barksdale Works19 Barksdale Field DNT Bio-Pilot 2008

July 22, 2008Former DuPont Barksdale Works Bio-Pilot Work Overview Reduction of DNT via biodegradation observed by GA Tech in studies funded by DuPont. Small field-scale pilot conducted in 2007 at Barksdale results promising, pilot scaled up in Pilot locations chosen based on manufacturing history (predominately DNT). Work started in June 2008 at four locations.

July 22, 2008Former DuPont Barksdale Works Pilot Locations Lydol House (4 cells from 2007) Trivilene No. 1 Sweating House TNT No. 4 Bi/Tri House TNT No. 2 Wash House

July 22, 2008Former DuPont Barksdale Works22 map of 08 inv priorities. SITES

Sweating Ho Trivilene #1 Sweating House

July 22, 2008Former DuPont Barksdale Works24 #1 Trivilene Sweating House Cell

TNT #4 Bi-Tri House BiTri Ho

July 22, 2008Former DuPont Barksdale Works26 TNT #4 Bi-Tri House Cell

TNT #2 Wash House Wash Ho BiTri Ho Neut. Ho divert SW

July 22, 2008Former DuPont Barksdale Works28 Barksdale Bio-Pilot June 2008 TNT02 Wash House Cell Prior to first tilling

July 22, 2008Former DuPont Barksdale Works29 # 2 Wash House Cell

July 22, 2008Former DuPont Barksdale Works30 Typical debris removed by raking

July 22, 2008Former DuPont Barksdale Works31 Lydol House Cells

July 22, 2008Former DuPont Barksdale Works32 Tractor with Howard Rotovator 700 DUT

July 22, 2008Former DuPont Barksdale Works33 Tilling No. 2 Wash House

July 22, 2008Former DuPont Barksdale Works34 Pilot Status All locations tilled approximately once per month Periodic sampling for Nitramine and nitroaromatic organic compounds pH Nitrogen, Phosphorus, and Potassium Adjust pH in cells as necessary

July 22, 2008Former DuPont Barksdale Works35 Continue to investigate high priority areas on-site: Focus on high priority areas, including characterization and remediation. Barksdale Path Forward

July 22, 2008Former DuPont Barksdale Works36 Map of priority areas of investigation. Use map from April 2

July 22, 2008Former DuPont Barksdale Works37 Continue biodegradation studies. Continue to address DNX isomer and As/Pb issues. Continue public interaction and water supply commitments. Barksdale Path Forward

Chequamegon-Nicolet National Forest Update

July 22, 2008Former DuPont Barksdale Works39

July 22, 2008Former DuPont Barksdale Works40 Chequamegon-Nicolet National Forest Project Summary: DuPont working in conjunction with the US Forest Service (USFS) to investigate two sites (Cabin Lake and Clover) in the Chequamegon- Nicolet National Forest. Delineation of debris, via geophysical surveying, was the first investigation step: Delineation completed at Cabin Lake in late 2006, while debris delineation was completed at Clover in May Debris delineation report submitted to USFS on June 7, 2007.

July 22, 2008Former DuPont Barksdale Works41 Chequamegon-Nicolet National Forest Completed field portion of the Phase II Archaeological investigation in June 2008 Approximately 1,500 man hours of field work. Excavated 188 Shovel Test Pits (STPs) and 17 Test Units (TUs). Recovered artifacts that appear to be associated with past logging activities. Artifacts shipped to URS’ archaeology lab in Maryland for further study and curation preparation. Report preparation underway. Expected submittal to agency before the end of the calendar year. USFS and Wisconsin State Historical Preservation Office will determine if the site is eligible for National Historic Register of Places.

July 22, 2008Former DuPont Barksdale Works42 Chequamegon-Nicolet National Forest Path Forward: Once the archaeological work is reported and a determination as to what extent, if any, the logging site will need to be addressed as part of planned environmental work at Cabin Lake, DuPont will submit the final work plan for environmental investigation of the Clover and Cabin Lake sites to USFS for review. The environmental investigations at Clover and Cabin Lake are planned for 2009, pending USFS approval to proceed.

July 22, 2008Former DuPont Barksdale Works43 Questions or comments?