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Procedures for Detection and Quantitation

Policy Workgroup

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

Summary of Policy Work Group Conference Call #18
September 28, 2006
1:00 – 3:00 p.m. EST

Calls will be held from 1:00 to 3:00 PM, Eastern Time, on the following dates: October 18 and 26, November 1, 9, 15 and 29.

The call in number is 1-866-299-3188, and the access code is 202-566-1000#.

Action Items

Dave Akers will distribute to the group the Colorado approach to account for matrix effects.

Larry LaFleur will transmit to the Technical Work Group at its next meeting the request from the Policy Work Group to investigate the feasibility of developing recommendations around the issue of matrix effects.

Triangle will work with Tom Mugan and Dave Akers to incorporate previously-stated concerns and issues with each of the three uses proposals currently being discussed. Triangle will then circulate the three proposals (in one document) to the Policy Work Group for discussion among constituents in preparation for discussion again at the October 26 group meeting.

Welcome and Introductions

Facilitator Alice Shorett convened the conference call at 1:00 PM ET and called the roll of participants. She briefly reviewed the agenda with participants, saying the primary focus of the meeting was the alternative uses proposals distributed by Tom Mugan prior to the call. She said the group would also discuss matrix effects and consider tasking the Technical Work Group with considering some approaches to address matrix effects.

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Meeting Summary Review and Approval

Ms. Shorett asked for comments to the draft summary from the September 20 Policy Work Group (PWG) meeting. David Kimbrough wanted to clarify that at the last meeting the group added two more items to discuss in the near future: a prescribed detection limit and verification. Ms. Shorett said those items were identified in the draft summary for future discussion. There were no other comments and the summary was approved as drafted.

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Revised Uses Straw Proposals

Tom Mugan summarized for the group the contents of two documents he distributed prior to the meeting. Both were revised versions of the State caucus "uses" proposal presented at the July FACDQ meeting. He said one of the proposals reflected the revisions from previous Policy Work Group discussions.

He developed the other proposal based on subsequent conversations, and he cautioned that this latter proposal had not been vetted within his own caucus. He said that states want the data, and it was most efficient to keep all the data in one database. This latter proposal was a way for states to get data between the QL and DL, and to use data in the calculations of a compliance evaluation threshold. Dave Akers added that values between the quantitation limit (QL) and the detection limit (DL) would be counted as zeroes for averaging purposes.

Ms. Shorett asked for comments from the group on each of the proposals.

Roger Claff asked for clarification whether Mr. Mugan's alternate proposal included reporting data below the QL on a discharge monitoring report (DMR), because that would be an issue for his constituents. Mr. Mugan responded that was true. David Kimbrough said that the Clean Water Act includes provisions for third party lawsuits. Allowing for the reporting of uncertain data below the QL opens the door for citizen suits. Mr. Mugan responded that the group would indeed need to be very careful about the wording of the certification statement on the DMR, as well as put into place a robust system for flagging data. Mr. Claff said the states will need to be explicit as to how data below the QL would be used.

The group then moved into a discussion of what states currently use for data in calculating monthly averages. Some states use zero while others have guidance suggesting the use of "less than [the value of the quantitation limit]." With regard to accuracy, some members of the group commented that the practice of using zero for averaging is no more accurate than the practice of using the actual values or some surrogate of the value. Others highlighted the issues of using uncertain data for regulatory decision-making. The group agreed that committee recommendations for setting policy should be based on what makes the most practical and technical sense and should not be encumbered by current practices.

Michael Murray suggested that no matter which direction the Policy Work Group decides to make its recommendation to the committee, the rationale for that choice must be completely transparent. He said the issue is what is done with reporting numbers below some level of certainty. Barry Sulkin agreed and said that his preference would be to use the actual numbers with a footnote that limits liability of those numbers below a certain point because of the uncertainty of the data.

Cary Jackson said the topic is one from which the lab caucus has generally abstained. However, the issue needs to be addressed and resolved in order for the committee to move forward. Nan Thomey agreed that the lab caucus has abstained from the issue so long as it does not create different tiers of reporting from the labs to their customers. She said she made the suggestion at the 4th committee meeting to report some flagging convention (e.g. detected but not quantified) with the upper and lower bounds as a way to reach consensus on the issue.

Roger Claff said that he had not had time to send the alternate proposal around to his members, but his first glance tells him that they would not be happy with the requirement to report data on a DMR below the QL. Larry LaFleur agreed with Mr. Murray that the group needs to be completely transparent with its rationale. He also said that while he does not want to discredit the effort Mr. Mugan put into trying to find compromise, the industry caucus has consistently said there are no good regulatory uses for numbers below the QL. This alternate approach proposed by Mr. Mugan effectively strips the flag from the value and treats it with the same stature as other numbers, when we know it is a much less certain number than those above the QL.

Barry Sulkin responded by saying the group is perhaps back to the original proposal to report "detected but not quantified" below the QL.

Mary Smith said that she did not have a lot to add to the discussion. It would appear as though all the proposals are on the table. Now the group needs to work on whether it can make a recommendation to the committee, and whether it will be a consensus recommendation.

Nan Thomey asked if everyone in the group was comfortable with labs reporting values with j-flags to their customers. Some responded that they were not really sure; others said they just wanted a way to get at that data, while others responded that what happens between the lab and its customer is not within the purview of the committee to discuss. Some participants supported this based on the notion that the more information the better, but that the intent was not to set up a dual system for lab reporting.

Ms. Thomey responded by asking whether regulating agencies and environmental groups knowing that the permittee has the data opens the door to negotiations on what is reported. For instance, this information could be available during regular annual inspections. David Kimbrough responded by saying the utilities are not opposed to sharing the information. However, they also do not want it used against them for compliance purposes. Ms. Thomey said if that is the case, then the group should recommend changing the certification statement on the DMR.

All caucuses agreed to move forward with discussing all three of the existing proposals within their caucuses and as a group. Ms. Shorett clarified that the three proposals currently on the table are:

  1. the state proposal at the July committee meeting;
  2. the revised state proposal; and
  3. an alternate proposal from Tom Mugan.

Ms. Shorett said Triangle will put all three proposals into one document. The facilitation team will then work with Mr. Mugan and Mr. Akers to incorporate all of the previously-stated issues and concerns into each proposal as a footnote for members of each caucus to circulate to their constituents. She asked the group to come prepared to the October 26 Policy Work Group meeting to discuss compromises and a way forward on a recommendation for the committee to consider in December.

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Matrix Effects

Ms. Shorett asked Larry LaFleur to begin a discussion on the topic. Mr. LaFleur reminded the group of his original document distributed a few weeks ago that laid out some options for the committee to explore with regard to matrix effects. He said that at the time, the facilitation team asked for comments on his discussion document. Representatives from two caucuses responded, including his.

David Kimbrough said that he understands all the issues. His concern is that it is such a big issue that he is worried the committee and workgroups are not going to have the time to address the issue. Dave Akers said that he had indicated in the past that Colorado does have a way to account for matrix effects. The group asked if Mr. Akers could distribute Colorado's approach to the group.

The group talked about the tendency to use matrix effects as an excuse for maintenance issues. From the laboratory standpoint, matrix effects occur on a site-by-site basis, which would make incorporating every possibility into one approach very difficult. Some in the group echoed Mr. Kimbrough on the concern of the current workload and the time remaining to seek consensus recommendations of the committee on procedures and uses.

On the other hand, many in the group recognized this as such a severe shortcoming of the current approach to method promulgation that it would be worth the committee's time to discuss the matter, even if it only resulted in general comments on the issue in the final report.

The group agreed to ask the Technical Work Group to consider whether this was an issue worth exploring. If so, Mr. LaFleur suggested the Technical Work Group be asked to:

  1. Develop a cost-effective procedure to demonstrate the existence of a matrix effect; and
  2. Make recommendations or develop procedures for developing matrix specific DLs and QLs.

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Wrap Up and Adjourn

Alice Shorett briefly reviewed the schedule of remaining calls and discussion topics with the group. She thanked all for their participation and concluded the call at 3:00 PM (ET).

Attendance

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