Jump to main content.

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 #11
October 19, 2005
1:00 – 3:00 p.m. EDT

The next Technical Work Group call is scheduled for Wednesday, November 9, from 1:00 - 3:00 PM EDT.

Action Items

Richard Reding will

Jim Pletl will further refine the description of characteristics based on comments from Technical Work Group members and redistribute a draft by middle of next week.

The Single Lab Subgroup (Richard Burrows - lead, Cliff Kirchmer, Ken Osborn, Brad Venner, David Kimbrough and John Philips) and the Multi Lab Subgroup (Larry LaFleur - lead, Bob Avery, Jim Pletl, and Steve Wendelken) will

Ken Osborn will distribute via email the Technical Work Group refinements he made tthe Osborn Lab QC procedure.

Triangle will:

Top of Page

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. Mr. Wheeler emphasized the purpose of the meeting was to check the progress of the two subgroups, discuss modifications to procedures that were identified at the October 5, 2005 Technical Work Group meeting as procedures needing refinement, and discuss revisions to the description of characteristics.

Richard Reding of EPA commented that while a pilot study is still budgeted, that budget amount would be somewhat less than expected. Mr. Reding asked members to keep in mind, among other logistical considerations, economical ways of testing procedures.

Mr. Wheeler briefly reviewed the assignment from the federal advisory committee tthe Technical Work Group.

Mr. Wheeler asked for comments on the October 5, 2005 draft Technical Work Group meeting summary. Jim Pletl asked for clarification on page 3, subtopic 5 (a) under purposes and objectives. Members discussed the necessity in setting the benchmark of achieving an intended purpose at or better than the MDL. The discussion concluded with members agreeing to delete the subtopics under #5 and adding a parenthetical statement to read:

Does the procedure achieve its intended purpose (i.e. does it implement the definitions adopted by the FACDQ)?

Committee members approved the October 5, 2005 summary with the suggested revision to page 3.

Top of Page

Report from Subgroups

Mr. Wheeler asked for progress reports from the two subgroups. Larry LaFleur reported for the Multi-Lab Subgroup saying that the subgroup had not yet met. He said he had circulated via email some concepts and an outline for discussion among the subgroup, but reiterated that those were his own thoughts and not a product of the subgroup.

Richard Burrows reported for the Single-Lab Subgroup saying that they also had not yet met, although the subgroup's first meeting was planned for this Friday, October 21. He also reported that the subgroup has one additional member: David Kimbrough. Mr. Burrows said that Mr. LaFleur's approach looked like a good one and that he was proposing the Single-Lab Subgroup discuss the issues in the same way.

Members of the Technical Work Group then moved into discussing the purposes and objectives of the pilot study, using as a starter list the five identified in the October 5, 2005 meeting summary. The group agreed that while the desired outcome of the pilot study is to have identified a procedure with which to move forward, the more likely scenario is that the pilot will identify a few of procedures that may need further refinement. Ultimately, the decision will be made by the federal advisory committee, but the hope is that the pilot test will do a good job of identifying the strengths and weaknesses of those procedures that are pilot tested.

In the course of discussing some concepts of a study design (i.e. use of existing data, written procedures, long-term vs. short-term, blank correction, spikes, performance measures) the following purposes and objectives were identified as a starter list for the two subgroups to work through in designing a pilot study:

  1. Is the procedure clearly written?
  2. Can the data be easily processed in the laboratory?
  3. Was the procedure correctly implemented?
  4. Does the experimental design unduly influence the outcome of the study?
  5. Does the procedure achieve its intended purpose (i.e. does it implement the definitions adopted by the FACDQ)?
  6. How can the procedures and analytically methods be narrowed to a smaller number to pilot test?

Mr. Wheeler summarized the discussion and reminded the subgroups that they would need to complete a product for discussion at the November 9 Technical Work Group meeting.

Top of Page

Discussion of Modifications to Procedures

Mr. Wheeler started the discussion by reminding the group that the federal advisory committee clearly articulated the need for a clear, written procedure. At the October 5 Technical Work Group meeting, the following procedures were identified as ones needing further refinement:

Cliff Kirchmer, representing the state caucus, said that he had contacted the Water Research Centre in England asking for a step-by-step written procedure, but they did not have one. In short, he edited a procedure he had previously drafted and sent out to the group, adding clarification around the assumptions, but did not add a step-by-step process for conducting the procedure. As the procedure stands to date, it is a good one for determining a detection limit where there is variability of a blank response.

Ken Osborn of the public utility caucus said that he also made revisions to the Osborn Lab QC procedure. He said he would circulate via email to the group the revised procedure.

Mr. Wheeler suggested the two subgroups look at the five procedures identified above and make a recommendation back to the full group on how to move forward. Keeping in mind that the federal advisory committee will ultimately want to narrow the list of procedures being pilot tested, the subgroups recommendations could help move this discussion forward.

In response to a question from Mr. Wheeler, the Technical Work Group members agreed that they were not charged with revising any of the other procedures at this time, although that need may exist after evaluating results of the pilot test.

Top of Page

Discussion of Revisions to Descriptions of Characteristics

Mr. Wheeler reminded the group that Jim Pletl sent suggested revisions to the document via email. He asked Mr. Pletl to walk the group through each of those suggested revisions and suggested the group reach conclusion on necessary revisions. In addition to general formatting corrections, Technical Work Group members agreed to the following revisions (which Jim Pletl will revise and send out for final consideration at the next Technical Work Group meeting):

Top of Page

Public Comment

There were no public comments.

Top of Page

Wrap-up and Closing

Mr. Wheeler 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, and said the agenda for the next call would focus on reports from the subgroups. He also said that Triangle was working with Mr. Reding to revise the glossary of terms and would circulate a revised document for discussion at the next meeting. He indicated that the two Pilot Study work Groups had three weeks to complete their assignments, but should aim to send their results out at least a few days ahead of the November 9th Technical Work Group meeting so members have time to review the recommendations. He thanked Technical Work Group members for their time and closed the meeting at 3:00 p.m. EDT.

Top of Page

Attendance

Technical Work Group Members

Triangle Associates: Derek Van Marter and Robert Wheeler

Observers

Top of Page

Local Navigation

Jump to main content.