DuPont Barksdale Site Sampling and Analytical Presentation December 12, 2001 Northern Great Lakes Visitors Center

Tonight’s Presentation Residential Sampling Why, When, Who, & How Analytical Program Lab Selection Lab Methods Reports Independent Review Communications Next Meeting Brad Nave Harry Gearhart

Residential Water Sampling Why sample the drinking water? Chemicals from the DuPont Barksdale Site have been found in the groundwater. DuPont and the Wisconsin Department of Natural Resources want to know if the chemicals are in drinking water so that corrective action can be taken.

Postcard Reminder for Residential Sampling

Residential Water Sampling What are you sampling for? The primary chemicals DuPont and WDNR are looking for are called Nitroaromatic and Nitramine compounds, which were used to make explosives at the DuPont site. DuPont and WDNR have also checked for many additional chemicals.

Residential Water Sampling How is the water sampling done? Experienced sampling personnel collect the water samples in EPA approved clean containers. Samples are collected in resident’s homes at various locations, including at the tap. Many homes now have water treatment systems, where samples are also collected.

Residential Water Sampling How is the security of the samples maintained? Special seals are placed on the cooler lid before and after sampling event. A form called a Chain of Custody is used to track who handles the samples.

Chain of Custody Example

Residential Water Analytical Program Objectives Obtain accurate and reliable results for low levels of explosive compounds and other test parameters. Receive results in a timely manner. Use a reputable laboratory.

Laboratory Selection Few commercial laboratories in USA can analyze for very low levels of Nitroaromatics and Nitramines with High Performance Liquid Chromatography - Tandem Mass Spectrometry (HPLC-MS/MS), based on SW846 Method 8321A.

Laboratory Qualifications Severn Trent Laboratories - Denver, CO Wisconsin certified for explosives US Army Corp of Engineers (USACE) approved for explosives

Laboratory Analysis and Reporting Use WDNR approved analytical methods Generate lab report

Analytical Method Summary The HPLC-MS/MS analysis, based on Method 8321A, involves a multi-step analytical procedure: Explosive compounds are extracted from a water sample by a solid phase extraction process (SPE). A solvent is used to remove the compounds from the SPE cartridge into a small final volume.

Analytical Methods (continued) High performance liquid chromatography (HPLC) is used to separate the explosive compounds present in the sample extract. The HPLC is coupled with a tandem mass spectrometer (MS/MS) for positive identification and quantitation of compounds based on the generation of mass spectra.

Mark Dymerski, LC/MS Group Leader Dr. Steve Cowling, LC/MS Chemist

Analytical Methods (continued) Additional Analytical Methods for other parameters. Sulfate by EPA Method 300.0 Nitrates/Nitrites by EPA Method 353.2 VOC’s by EPA SW846 Method 8260 Metals by EPA SW846 Methods 6010, 6020, or 7470

Analytical Method Quality Control Analysis sequence with quality control elements and acceptance criteria Instrument set-up Calibration and calibration verification Method & procedure quality control Sample matrix quality control

Field Quality Control Samples Field sample Duplicates at a minimum of 5% Field sample fractions for Matrix Spike & Matrix Spike Duplicate at 5% frequency or per event, whichever is greater

Other Quality Control Laboratory systems quality control three separate levels of review Agency oversight/approval on-site audits certification Proficiency Test samples DuPont audits

Full Laboratory Report Deliverables Content for explosives follows EPA “National Functional Guidelines for Data Validation” Intended to: allow independent review of all details of qualitative and quantitative determination of analytes in samples provide in-depth determination of data usability summarize sample results

Independent Data Review Performed as a voluntary effort as an additional quality control step Not performed on all projects

Independent Data Review (continued) Independent validation of explosives data is performed by Environmental Standards, Inc. (ESI), Valley Forge, PA Nationally-recognized validation and quality assurance specialists Data review protocol based on EPA “National Functional Guidelines for Data Validation”

Independent Data Review (continued) Role of Independent Data Validator: Evaluate procedures and associated data Specify lab rework Request additional documentation Add data qualifiers Flag unusable data Provide detailed report on compliance and data usability

Independent Data Validation Process Includes an in-depth examination of the following data elements: Sample condition/security upon receipt Sample holding times Sample preparation Analytical sequence Initial and continuing calibrations Analyte identification Analyte quantitation

Independent Data Validation Process Includes an in-depth examination of the following additional data elements: Blank analysis results Surrogate recoveries MS/MSD recoveries and precision Laboratory control spike recovery Field duplicate precision Field blank results

Reporting Laboratory sends the completed data report to the Independent Data Validator and DuPont Validator sends the final Quality Assurance Review to DuPont

Reporting and Follow-up DuPont forwards a summary of lab results and the independent review text report to WDNR and Division of Public Health. DuPont takes corrective action as appropriate. Wisconsin Department of Natural Resources sends a summary letter to residents.

Sample Results Who receives the analytical results and independent review report? Wisconsin Department of Natural Resources Wisconsin Division of Public Health DuPont

Sample Results If I have questions, who do I call? Wisconsin Department of Natural Resources Doug Shultz at (715) 372-4866 Chris Saari at (715) 372-4866, extension 120 Division of Public Health Henry Nehls-Lowe at (608) 266-3479 Bayfield County Health Department Millie Lindsey (715) 373-6109 DuPont Brad Nave at (502) 569-2148 Bradley.S.Nave@usa.dupont.com 24-hour operator - toll free @ (866) 833-7875

Questions?

Next DuPont Barksdale Meeting January 22, 2002 Washburn Museum 7:00 P.M. Subject: Environmental Investigations Objectives Considerations Techniques

Presentation Materials Copies are available for: Groundwater Primer (October 30, 2001) Presented by Jim Richenderfer Historical Review (November 27, 2001) Presented by Mark Vetter