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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 #19
October 18, 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 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

A subgroup (composed of David Kimbrough, an Environmental Lab caucus member, and other members) will prepare a summary of issues in verification.

Mary Smith will send Triangle, for Policy Work Group distribution, a few summary spreadsheets of MQOs for current methods.

David Kimbrough will review 40 CFR Part 122 to assess whether this would be a better fit for his idea of a table of limits.

Triangle will call Policy Work Group members Nan Thomey and Carey Jackson of the Environmental Lab caucus to discuss and confirm their support of decisions reached on the call. Triangle will also ask Cary Jackson to review Note 1 in the merged hybrid approaches document.

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 to discuss and approve the merged hybrid document from Tom Mugan and Larry LaFleur.

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Meeting Summary Review and Approval

Ms. Shorett asked for comments to the draft summary from the September 28 Policy Work Group (PWG) meeting. The Policy Work Group requested no changes to the summary and approved it as drafted.

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Merged Hybrid Approaches

Alice Shorett opened the discussion and said there were 4 key issues the group needed to discuss:

Tom Mugan summarized the revised version of the merged hybrid approach. He identified the notes added to the document based on the group's discussion at its last meeting.

Ms. Shorett then asked the group to discuss each of the issues in order. Mr. LaFleur added for clarification that where the uses document (to be discussed at the next PWG meeting) references a QL, it is the same as the nationally-promulgated QL described in the merged hybrid approaches document.

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Recommendation for a prescriptive QL and a prescriptive/descriptive DL

All Policy Work Group members support a nationally-promulgated QL. Michael Murray repeated concerns he had previously expressed about keeping current a nationally-promulgated limit. He also reiterated his concerns that a prescriptively-set limit may be higher than a descriptively-set limit.

With regard to Note #1 in the "Merged Hybrid," all Policy Work Group members agreed that the representatives from the Environmental Lab Caucus, who were absent from the meeting, needed to review this note for accuracy and add more detail as appropriate. Bob Wheeler from Triangle agreed to contact both members of the caucus via telephone and explain to them the request from the group.

Ms. Shorett then asked the group to express their support for or against the recommendation to nationally promulgate a DL.

Tom Mugan introduced the discussion by saying he originally envisioned the "Merged Hybrid Approach" as a prescriptive QL and a descriptive DL. That type of hybrid approach led to the idea that labs would generate the lowest levels they could and then supply that information to EPA for future updates; an idea that was incorporated into the proposal. However, that approach has raised concern of not providing a level playing field for labs or the regulated community, particularly for data in the region between QL and DL.

Mr. LaFleur added that the committee also has not identified a use for DL. When it does, he suggested it will be clearer how DL is handled and set. Mr. LaFleur described a possible scenario with a prescribed QL for setting compliance, a prescribed DL for lab demonstration of proficiency (QA/QC), and a descriptive approach to be used by labs for their clients. Mr. LaFleur said the questions were whether a prescribed DL was needed and why it was needed.

David Kimbrough reiterated his position that if anything is to be reported below QL, the DL must also be prescribed to achieve the level playing field previously discussed. Conversely, he said, if nothing is reported below the QL for compliance purposes, it makes no difference if the DL is nationally-promulgated. Mr. Kimbrough added that under the Safe Drinking Water Act, the nationally-promulgated QL is treated as a ceiling. Individual labs are allowed to pursue lower limits through descriptive, individual lab processes. At a minimum, the labs must demonstrate they can meet the ceiling.

Michael Murray said he was unsure what incentives exist for labs to demonstrate a capability to achieve results lower than a prescriptively-set QL. Mr LaFluer added that from what has been heard from the labs, there is substantial competition among the lab community so that demonstration of lower levels should occur.

If a DL is prescriptively set, Mr. Murray indicated his concern about how DL levels would be set. However, he said he could see the benefit in allowing for a proficiency demonstration for a lower DL. Mr. Murray said he can accept the notion of a prescriptively set DL and QL for the purpose of moving a recommendation forward to the committee, if his concerns about setting QL and DL levels are registered.

Mary Smith said it sounded as though the group was open to the idea of nationally-promulgated limits (DL and QL) and a descriptive approach to meet individual lab needs.

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Publication of a table of limits in a promulgated rule

Ms. Shorett turned the group to a discussion of a table in a rule. She summarized the two types of tables that have been put before the group as follows: Both approaches list the analytes and the analytical methods available for each analyte. One approach includes a QL and DL for each method. For one analyte, there would be different QL's and DL's depending upon the method's capabilities. A second approach would list one DL and one QL for each analyte, no matter what method is used. In addition, this approach would identify MQO's for each analyte. She asked Larry LaFleur and David Kimbrough to further describe for the group the differences in the two approaches.

David Kimbrough said the table he has in mind includes one limit for QL and one limit for DL for all methods available to test each analyte. Identifying one limit creates a level playing field. Mr. Kimbrough said that for those situations where the WQBEL is below the QL, there is often only one approved method. This diminishes the need to distinguish from the use of the most sensitive method. In other cases where there is more than one approved method for an analyte, there are so many factors to consider that he challenges the idea that one method can be more sensitive than another in all situations.

Larry LaFleur described another option that would be published in 40 CRF Part 136, and that would list for each analyte the limits associated with each approved method for that analyte. For instances where the WQBEL is below the QL, the most sensitive method would be used to set the permit limit. Mr. LaFleur said that the committee would need to define what it means by the most sensitive method, to avoid any future confusion. Tom Mugan added that he had distributed the language from the Great Lakes Initiative that shows how a WQBEL that is below the QL is handled in an existing regulation.

The group then discussed the notion of using the most sensitive method to determine a permit limit. Some members believe that there are so many factors that affect analytical methods that there cannot possibly be a most sensitive method for every situation all the time. Other members believe that a tendency towards the most sensitive method in situations where the WQBEL is below QL will result in the lowest limit achievable by those methods approved for a particular analyte.

The group also discussed an appropriate location for a table and which type of table would be appropriate for that location (i.e. Part 136 or Part 122). Most of the group felt that the table would be appropriate in CFR Part 136 but not appropriate for CFR Part 122. It was agreed, however, that David Kimbrough would assess whether the table he envisions would better fit in CFR Part 122. David also agreed to provide a narrative description of what he is intending that could fit into the "Modified Hybrid" document.

After considerable discussion on the use of a table, the group agreed that a table should be published in a final rule. However, the group did not agree on the specifics of how a table would be sorted and populated pending further development and discussion of the issues.

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Process for verification

On the issue of verification, Larry LaFleur said the question the committee needs to discuss is what level of verification is needed. He said his caucus talked about a more frequent verification process than what is currently required in the ACIL or MDL procedures. The decision is a balance between costs versus the value of the information the verification process returns. He suggested that it would be useful for a small group to get together to outline the details for the Policy Work Group to consider.

David Kimbrough indicated that his idea is to verify batch-by-batch. Chris Hornback said that the Public Utilities caucus has not talked about the specifics of verification (i.e. frequency), but he agreed it was an important issue to his caucus. He said he has heard other caucuses suggest that the batch-by-batch frequency would not work, but he admitted that he needed to understand more of the issue before being able to decide.

The group agreed that a sub group could synthesize the verification issue in an effort to develop a recommendation to the Policy Work Group for discussion in December. David Kimbrough offered to participate in the subgroup. Alice Shorett said that Triangle would ask for participation from the Environmental Lab caucus when the facilitation team talks with them about the topics from this meeting.

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Wrap Up and Adjourn

Alice Shorett briefly reviewed the schedule of remaining calls and discussion topics with the group. She said that the group, in coming meetings, will need to work through uses and MQOs. She also said she would be sending materials out to the group in preparation for these discussions. Mary Smith said she had her staff pull together some summary spreadsheets of MQOs for a few existing methods that she would share with the group. Ms. Shorett thanked all for their participation and concluded the call at 3:05 PM (ET).

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