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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 #37
August 30, 2006
1:00 – 2:15 p.m. EST

The Technical Work Group's regularly scheduled call was held on Wednesday, August 30 from 1:00 p.m. - 2:15 p.m., EDT. The call-in number for all calls is 866 299-3188 and the participant code is 202 566 1045#. The schedule of future Technical Work Group conference calls is:

Action Items

Ken Miller will provide sample graphs from his analyses to the Technical Work Group as he proceeds.

Larry LaFleur will work with Nicole Shao and Larry Wymer of ORD to further develop their document on data calculations/analyses and why a side-by-side comparison of the numerical detection and quantitation limits derived by the procedures may not be appropriate.

Various individuals were assigned the task of filling in the Procedures 101 template and forwarding to the Technical Work Group.

Triangle will:

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Welcome and Introductions

Bob Wheeler, facilitator, welcomed participants to the call at 1:00 p.m., conducted a roll call of Technical Work Group members and observers, and briefly reviewed the agenda for the meeting.

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Meeting Summary Approval

Mr. Wheeler asked for comments on the draft August 16 meeting summary. Larry LaFleur asked for clarification in the discussion of the matrix effects. He understood that he was simply preparing something for discussion at the Policy Work Group and would keep the Technical Work Group apprised of the discussion. There were no other comments, and the summary was approved as revised.

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TWG and Pilot Design Team Schedule

Mr. Wheeler referred to the Technical Work Group and Pilot Design Team Schedules document and focused on three items for the next meeting on September 13. Mr. Wheeler suggested that one item on the schedule for the next meeting (considering ongoing verification) is not currently tied to a specific effort by an individual or subgroup of the Technical Work Group. Larry LaFleur said that he is working on developing two documents for the Policy Work Group discussion (matrix effects and a prescriptive-descriptive hybrid approach) that may aid in these discussions at the Technical Work Group level. Mr. LaFleur said that on-going verification is ultimately a policy call, so he suggested the Technical Work Group not spend a lot of time discussing the issue at this time. Mr. Wheeler said he would leave the item on the agenda for now to see how it plays out at the next Policy Work Group meeting on September 6.

Bob Wheeler circled back to a conversation that occurred at the last Technical Work Group meeting and subsequent to that regarding comments from EPA's Office of Research and Development (ORD) regarding its evaluation of the IDE procedure. He asked Nicole Shao, EPA ORD, if she wanted to follow-up with the group. Ms. Shao said that ORD and others conducted a teleconference on this subject and came to the conclusion that since ORD was not at this time recommending any changes to the IDE procedure, it would be more appropriate to spend time evaluating the other procedures as the pilot study moves forward. Therefore, Larry Wymer will not be discussing the assessment of the IDE procedure at the September 13 Technical Work Group call as previously planned.

Tim Fitzpatrick asked whether the subgroup addressing intermittent blank contamination should be discussing the issue with regard to the pilot study or more broadly. Bob Wheeler said his understanding was to look at the issue in a broad sense. Other Technical Work Group Members agreed.

Bob Wheeler asked whether there were any thoughts on how to develop guidance for not meeting qualitative criteria, which is on the Technical Work Group schedule in late September and beyond. There were no specific recommendations, but the group did discuss how this issue came up and clarified what was needed for this task.

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Status Updates: FACDQ Extension and Pilot Study

Bob Wheeler said that EPA is planning to start the paperwork for an extension of the FACA charter.

An RFP for contractor preparation of samples has been released for the pilot study. The study as a whole is on schedule, but solicitation for contractors is about two weeks behind schedule. Ken Miller said he has already started getting the historic blank data from participating labs as well.

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Procedures 101 Presentation

Bob Wheeler thanked Tim Fitzpatrick for putting together a template for reporting on each of the procedures. He explained to the group that two procedures had been prepared using the template: IDE from John Phillips and Lab QC from Ken Osborn. The following assignments are still outstanding.

  1. MDL - EPA
  2. ACIL (D/Q) - Richard Burrows
  3. Consensus Group (D/Q) - John Phillips (w/ Ken Osborn)
  4. LCMRL and Hubaux-Vos - Steve Wendelken

Technical Work Group members made a few minor modifications to the template and asked Triangle to redistribute the template for use. The group also asked those developing the presentations to include their notes or any clarifications needed (particularly with respect to a characteristic that was answered as "maybe").

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MMA Data Discussion

Bob Wheeler asked Ken Miller if he had anything to report. Mr. Miller said he created data sets based on the decision at the last conference call to look at the misidentified data two ways. Mr. Miller asked if it would be helpful to see sample graphs that come out of the automated software. Members agreed that it would be helpful to see those graphs.

Bob Wheeler asked if Nicole Shao wanted to add anything as follow-up to the discussion of data analysis and calculations that occurred at the last meeting. Ms. Shao said that ORD was asked at the last conference call to expand upon why direct comparisons of procedures might not be feasible. She worked with Larry Wymer to draft the one-page document distributed to members prior to this conference call.

Larry LaFleur said he was thinking of seeing all of the reasons why side-by-side comparisons could not be made of the procedures. He also said he was thinking the discussion would get into the limitations of the procedures, which may come out in the "features of the pilot study" document. Larry LaFleur said he would work with Nicole Shao and Larry Wymer to see if there are ways to further the document that ORD prepared.

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Rationale for Definitions

Bob Wheeler said Triangle had sent to EPA various Technical Work Group and committee meeting summaries where definitions are discussed. Larry LaFleur suggested that the discussions about blank subtraction that occurred outside the context of definitions also be captured. The main point is to reconstruct how or why the group decided to deviate from the IUPAC definitions.

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Public Comment

There were no public comments.

Wrap-up and Closing

Mr. Wheeler summarized the items coming forward for the September 13 meeting:

  1. Status of FACDQ extension
  2. Update on Pilot Study
  3. Concerns with comparing pilot study determined limits by procedure
  4. Consider intermittent method blank contamination and make recommendation(s)
  5. Procedures 101

Richard Burrows gave a brief overview of the National Environmental Monitoring Conference that he was attending. He said there were some very good presentations and discussions of detection and quantitation going on at the conference. He said the materials would go on the website in the near future (www.nemc.us).

Mr. Wheeler reminded everyone that at the September 13 meeting, the group will go back to the 2-hour schedule (1:00 - 3:00 PM, ET).

Mr. Wheeler thanked everyone for their time and adjourned the meeting at 2:15 PM ET.

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Attendance

Technical Work Group Members

Triangle Associates: Robert Wheeler and Derek Van Marter

Observers

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