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Procedures for Detection and Quantitation
Federal Advisory Committee on Detection and Quantitation Approaches and Uses in Clean Water Act (CWA) Programs
Summary of Technical Work Group Conference Call #22
March 8, 2006
1:00 – 3:00 p.m. EST
- Future Meeting Dates
- Action Items
- Welcome and Introductions
- Approval of Draft March 1 Meeting Summary Rescheduled for March 10
- Agenda Review
- Report of Policy Work Group Activities and Decisions
- Single-Lab Subgroup Report
- Regression-based Subgroup Report
- Estimated Costs for Pilot Testing Various Procedures
- Proposed Procedures for the Pilot Test
- Discussion of the paper, Consequences of the Omission of L D Determinations for Censored Methods
- Draft Questions to the FACDQ and Possible Assignments from the March Meeting
- Wrap-up
- Attendance
- Back to Technical Workgroup home page
The next Technical Work Group call is scheduled for Friday, March 10, from 1:00 – 3:00 PM EST . The call-in number is 866-299-3188; access code is 202 566 1045#.
Future Meeting Dates
The remaining Technical Work Group call before the March 29-30 advisory committee meeting is scheduled for Wednesday, March 15, at 1:00 PM EST .
Action Items
The Technical Work Group agreed to the following action items during the conference call:
- Cliff Kirchmer will take the lead in revising the paper, Consequences of the Omission of L D Determinations for Censored Methods, to add and show in bold type his proposed changes as well as those hereceives from Technical Work Group members and distribute it to the Technical Work Group no later than Thursday at 4 PM PST so it can be discussed on the Friday (March 10) call.
- Larry LaFleur will distribute the draft Assessment of the Value of Existing Data for Regression-Based Design.
- Ken Miller will distribute his work, Single Lab Existing Data Evaluation.
- Dick Reding will revise the list of proposed procedures to reflect today’s discussions.
- Triangle is to send the draft summary of the March 1 Technical Work Group call to participants for review and approval on the March 10 call.
Welcome and Introductions
At 1:00 PM Bob Wheeler, facilitator, welcomed participants to the call, conducted a roll call of Technical Work Group members and observers, and briefly reviewed the agenda for the meeting.
Approval of Draft March 1 Meeting Summary Rescheduled for March 10
Mr. Wheeler noted that review and approval of the draft summary of the 1 March 2006 Technical Work Group meeting would occur on Friday, March 10. The draft was to be sent in advance of the call.
Agenda Review
The purposes of the meeting were to review Technical Work Group products to see if they were ready to send to the advisory committee or if additional work was needed to finalize them, to review draft Technical Work Group questions to the advisory committee and to review possible assignments from that meeting to the Technical Work Group.
Report of Policy Work Group Activities and Decisions
Mr. Wheeler briefly reported on the activities and decisions of the Policy Work Group, including its response to the Technical Work Group’s recommendation to set MQO’s before conducting the pilot test and to test procedures rather than a data-gathering pilot.
He said that the Technical Work Group’s recommendation had led the Policy Work Group to reconsider and to reverse its tentative decision to conduct a data-gathering pilot without setting MQOs in advance. Instead, the Policy Work Group now favored conducting a procedural pilot test with MQOs defined in advance. The MQO Subgroup which had agreed on a proposal for false positives on a February 14 call had scheduled another call on March 10 to develop a straw proposal on the three remaining high priority MQOs (false negatives, bias and precision) to take to the March 29-30 advisory committee meeting. This proposal would be drafted in light of identified uses (so all would be using the same assumptions) and using real data. The goal would be to have the advisory committee reach agreement on MQOs at the March meeting or, at the latest, at the July meeting. He added that the MQOs were to be for the pilot as well as for final procedure(s).
He also reported that Jim Pletl had aligned the high priority characteristics (which the Policy Work Group agreed to by consensus on February 27) with the objectives in “what we need procedures to do” and that Mr. Pletl would revise the resulting document based on comments he received from the Policy Work Group before it would be distributed with other pre-meeting materials.
He noted that the group had also worked on the document presenting and comparing prescriptive/descriptive approaches and that revised versions would be distributed in advance of the March meeting.
In response to a question about whether or not the Policy Work Group had developed questions for the advisory committee, Mr. Wheeler said that the group had not but that the decision trees and “uses” document had questions imbedded in them that would be discussed at the March meeting.
Single-Lab Subgroup Report
Richard Burrows reported for the subgroup. After considering the time and budget constraints that EPA had described on the previous Technical Work Group call, the subgroup had concluded that it was infeasible to conduct a data-gathering pilot to be followed by a procedural pilot and that the latter was more important. For a procedural pilot, he said they needed MQOs (false positives and negatives for the detection limit and bias and precision for the quantitation limit. Once the group had them, they could modify procedures to target those MQOs. It would be ideal to get the MQO’s at the March meeting, he said. He said they could then better reduced the number of procedures recommended to tested.
He then briefly reported on Ken Miller’s work on testing existing datasets and noted that the 524.2 dataset was “well-behaved” while the 502.2 was not, for reasons that were not yet clear. Mr. Miller then briefly described the work he was doing to determine limits to the data and the report he expected to produce.
Mr. Wheeler noted that Mr. Miller’s work would be the Single-Lab Subgroup’s product: a user-friendly report that explained his results, with the more detailed, technical information attached for those who wanted to go into greater depth. He said the goal was to have it by Friday. Larry LaFleur commented that the report on existing data needed to present an evaluation of how accurate the data are and how closely data align with what the method was intended to do. Mr. Miller said he would include that information.
Jim Pletl expressed a concern that Mr. Miller’s analysis was using analytical performance and the availability of tools to set MQOs rather than basing them on uses and the needs of the user. Instead, he argued, one should describe the desired outcome and then test the procedures to see if they can achieve it.
After discussion by a number of participants, it was agreed that the advisory committee would need to discuss the issue at its March meeting.
Regression-based Subgroup Report
Larry LaFleur reported for the subgroup. He said that the constraints EPA had described had made the regression-based/multi-lab approach obsolete but, since the advisory committee had requested the product, he wanted to finalize the report of what existing data could be used for and present it to the committee. He added that the subgroup had wrestled with how to confirm the estimates. The subgroup felt it needed to keep L D in the equation but that confirming L D would require additional resources. It was agreed that the Technical Work Group would review and sign-off on the document during the Friday (March 10) call so it could be distributed with other pre-meeting materials.
Estimated Costs for Pilot Testing Various Procedures
Richard Reding provided cost estimates for the five procedures proposed for testing in the pilot study. They ranged between $100 and $250.
Proposed Procedures for the Pilot Test
The Technical Work Group reviewed a draft table that identified proposed procedures and analytes for the pilot test. Changes made included the following:
Presenting a choice between 200.7 and 200.8 (rather than selecting either one)
- Adding total phosphorus to total cyanide as a choice for the analytes to be tested in 335.3
- Correcting the “subtype” for procedure 300 from GC/IC to IC
With these changes, the Technical Work Group agreed to send this document to the advisory committee with the other pre-meeting materials.
Discussion of the paper, Consequences of the Omission of L D Determinations for Censored Methods
Lengthy discussion of this draft resulted in a decision that Cliff Kirchmer would take the lead in revising the paper, Consequences of the Omission of L D Determinations for Censored Methods. It was agreed that he would add his proposed changes as well as those he received from other Technical Work Group members and show them in bold type and distribute the revised document to the Technical Work Group no later than Thursday (March 9) at 4 PM PST so it could be discussed on the Friday (March 10) call.
Draft Questions to the FACDQ and Possible Assignments from the March Meeting
Mr. Wheeler reviewed the draft questions the Technical Work group had identified as it developed products for the March meeting. During discussion of the draft, the following changes were agreed to:
All of the questions should be under the heading, “Questions from the Whole Technical Work Group” rather than associating some questions with either pilot study design.
- Richard Reding was to consolidate questions 2, 6 and 7 which were similar.
- Under #2, Richard Reding was to insert a list of pre-qualification criteria for contracting for pilot test services, for the FACDQ to review.
- A question was added to #9, as follows: Does the FACDQ authorize the Technical Work Group to modify procedures to meet specific MQOs?
It was agreed to review and finalize the document on the Friday call.
The Technical Work Group also reviewed and approved the list of possible assignments from the March FACDQ meeting.
Wrap-up
Mr. Wheeler summarized the action items from the discussion and reviewed the agenda items for the Friday call, as follows:
- Approval of Proposed Regression Pilot Study Design and Analysis of Existing Data Report
- Approval of Single-Lab: Report on Evaluation of Existing Data
- Approval of Consequences of the Omission of Ld Determinations for Censored Methods Report
- Final Questions and Assignments for the March meeting of the FACDQ
Mr. Wheeler thanked members for their hard work and reminded members that the next meeting was scheduled for Friday, March 10, 2006 at 1 PM EST. He adjourned the meeting at 2:55 PM EST.
Attendance
Technical Work Group Members
- States: Bob Avery, Cliff Kirchmer and Tim Fitzpatrick
- Environmental Laboratories: Richard Burrows
- Environmental Community: Richard Rediske
- POTWs: David Kimbrough, Ken Osborn and Jim Pletl
- Industry: Larry LaFleur and John Phillips
- US EPA: Richard Reding (Office of Water) and Brad Venner ( Office of Enforcement and Compliance Assurance)
- Other Federal: Bill Ingersoll, US Navy
Triangle Associates
- Robert Wheeler and Vicki King
Observers
- Tom Georgian (US Army Corps of Engineers)
- Ken Miller (Consultant to EPA Office of Water)
- Nicole Shao (Office of Research and Development)
- Steve Wendelken (Office of Drinking Water)