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Procedures for Detection and Quantitation

Technical Workgroup

Federal Advisory Committee on Detection and Quantitation Approaches and Uses in Clean Water Act (CWA) Programs

Summary of Technical Work Group Conference Call #6
September 7, 2005
1:00 – 3:00 p.m. EDT

The next Technical Work Group call is scheduled for Tuesday, September 13, from 1:00 – 3:00 PM EDT. Members also added an additional conference call for Thursday, September 15, from 3:00 – 5:00 PM EDT. Please see below for the schedule of subsequent calls.

Action Items

Richard Reding will

The subgroup on definitions of detection and quantitation (Steve Bonde, Cliff Kirchmer, Ken Osborn, John Phillips, David Rocke, and Brad Venner) will:

The subgroup on matrix of characteristics and procedures (Richard Reding, Timothy Fitzpatrick, Larry LaFleur, Jim Pletl, Richard Burrows, Richard Rediske, and Bill Ingersoll) will:

The MDL/ML subgroup (Larry LaFleur, Brad Venner, Cliff Kirchmer, and Richard Burrows) will finalize the draft discussion paper for the Technical Work Group to review and approve at the September 13, 2005 Technical Work Group conference call.

Triangle will:

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Welcome and Introductions

Robert Wheeler, facilitator, welcomed participants to the call at 1:00 PM EDT. He conducted a roll call of Technical Work Group members and observers, and briefly reviewed the agenda for the meeting. He added to the agenda a report from the Pilot Scope subgroup, and reviewed action items from the last meeting. Mr. Wheeler outlined the products that need to be completed and approved at the September 13, 2005 Technical Work Group conference call for distribution to the federal advisory committee:

Mr. Wheeler then asked Technical Work Group members for comments to the draft summary of the August 24, 2005 Technical Work Group meeting. There were no comments and the summary was approved, as drafted.

Mr. Wheeler then asked Technical Work Group members for comments to the draft summary of the August 10, 2005 Technical Work Group meeting. There were no comments and the summary was approved, as drafted.

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Report from the MDL/ML Issues Subgroup

Mr. Wheeler explained that the facilitation team is coordinating how this assignment from the federal advisory committee will work into the agenda for the two-day meeting at the end of September. He said most of the afternoon on the first day will be spent discussing detection and quantitation procedures, which makes the most likely fit for a report from this subgroup. He asked Larry LaFleur to describe where the subgroup is and its plans for completing the assignment.

Mr. LaFleur reminded Technical Work Group members that they received a revised version of the issue paper. There are some outstanding discussions on points #2, and #6. He asked subgroup members for their availability for a conference call today or tomorrow to resolve these discussions.

The subgroup members also clarified that their task was to clearly articulate for the federal advisory committee the concerns with the current MDL and ML procedures. They were not tasked with evaluating the concerns expressed regarding the current procedures. Mr. LaFluer expects that the subgroup is close to completing this assignment, and that it will be ready for discussion and approval at the September 13, 2005 Technical Work Group conference call.

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Report from the Definitions Subgroup

Mr. Wheeler explained that the definitions would be presented to the federal advisory committee through a panel of members from the subgroup. There is currently an hour set aside on the first day of the two-day meeting. Mr. Wheeler encouraged the presentation to respond, at a minimum, to the following three questions:

  1. Why was drafting definitions such a difficult assignment?
  2. Which definitions does your caucus propose using and why?
  3. What are your suggestions for moving forward with definitions?

The products presented to the federal advisory committee will include the definitions for detection and quantitation, and the accompanying white paper. Mr. Wheeler asked John Phillips to brief the Technical Work Group on the status of the subgroup and product development.

Mr. Phillips explained that the subgroup's preference is to complete the document with definitions for detection and quantitation, and keep in the glossary the other terms identified by the federal advisory committee. Mr. Phillips said the subgroup will forward the white paper and the definitions document for consideration by the federal advisory committee. The definitions document will contain options for Lc, Ld and Lq (i.e. statistical and laypersons' definitions).

The Technical Work Group discussed the issue of including the word "sample" in the definitions and its relevance to matrix effects. Members agreed that the word "sample" would remain in the definitions, but that the impact of this reference on a corresponding procedure would be described in the accompanying white paper.

Mr. Wheeler reviewed the timing of meetings and product development, and asked the subgroup members if they could have a draft white paper completed and ready for discussion at the September 13, 2005 conference call. Technical Work Group members agreed that the subgroup would need more time to draft the white paper and added an additional conference call to the schedule on Thursday, September 15, 2005 (3-5 PM EDT) to discuss and approve the white paper for distribution to the federal advisory committee.

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Report from the Characteristics-Procedure Matrix Subgroup

Mr. Wheeler said the matrix still needs final formatting prior to distribution to the federal advisory committee, and that Triangle would be taking care of that. The products going forward to the committee from this subgroup are the completed draft matrix and descriptions of the characteristics. Again, a panel of subgroup members will present the products to the federal advisory committee. The presentation should focus on the characteristics and the measures of those characteristics. The panel should also present which procedures were dropped from consideration and why they were dropped.

Mr. Wheeler said the federal advisory committee will break into small groups by interests to discuss the matrix immediately following the panel presentation. The result of the small group discussions will likely be detailed comments on the matrix and further assignments to the Technical Work Group.

Jim Pletl acknowledged that there may have been some confusion between the description of the characteristics and the corresponding measure in the matrix (e.g. "Relative Implications"). He offered to reverse the 1-10 measure and make other corrections for consistency between the matrix and the characteristics. Steve Wendelken of EPA offered to drop from consideration the Huvaux-Vos procedure with the justification that it is essentially included in the IDE/IQE procedure. Technical Work Group members agreed to this suggestion. Bill Ingersoll of the Navy confirmed that the Navy Uncertainty Calculation Procedure does not address detection. There was some question as to whether it was a quantitation limit procedure. Mr. Ingersoll said he would contact Steve Bonde to understand why Mr. Bonde wanted it included for evaluation as a procedure.

Mr. Wheeler said that once Mr. Pletl completed refinements from the Technical Work Group, Triangle would send to members the latest version of the matrix and description of the characteristics. He asked those assigned to fill in the matrix to take another look at their answers and return the completed matrix to Derek Van Marter at Triangle by Friday, September 9, 2005. Mr. Wheeler also asked Mr. Pletl to draft an introductory paragraph to the matrix for presentation to the federal advisory committee. He said the Technical Work Group would review and approve a final version of the matrix and description of the characteristics at the September 13, 2005 Technical Work Group meeting. Mr. Wheeler also confirmed with Technical Work Group members that the "statistical attributes" spreadsheet would not be a federal advisory committee product, but would serve as a working document for Technical Work Group members.

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Report on Development of a Glossary of Terms

Mr. Wheeler explained that as follow-up to an action item from the last meeting, Triangle worked with Richard Reding to compile a glossary of terms that incorporated many terms from the three glossaries previously distributed to Technical Work Group members. He asked members to review the glossary and send comments to Triangle and Mr. Reding. Mr. Wheeler added that the glossary should be near final by the next Technical Work Group meeting.

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Public Comment

Mr. Wheeler invited observers to offer comments.

Ken Miller, a contractor to EPA, commented that there is a disconnect between the definitions and glossary of terms regarding Lc, Ld, Lq and False Positives/Negatives. The final definitions for False Positives/Negatives will depend on the final definitions that the federal advisory committee chooses for detection.

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Wrap-up and Closing

Mr. Wheeler reminded members that it is important to finalize products. After next week, the focus should shift to developing presentations of the products for the federal advisory committee. He reminded participants that the dates and times (all are EDT) of future Technical Work Group meetings are as follows:

Mr. Wheeler briefly noted the action items from the call, thanked Technical Work Group members for their participation, and closed the meeting at 3:00 p.m. (EDT).

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Attendance

Technical Work Group Members

Triangle Associates: Derek Van Marter and Robert Wheeler

Observers

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