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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 #15
August 23, 2006
1:00 – 2:30 p.m. EST

Calls will be held every other week, 1:00 - 3:00 PM ET. The schedule of remaining calls is: September 6th and 20th, October 4th (The October 4 call may be rescheduled due to the National Association of Clean Water Agencies (NACWA) National Pretreatment and Pollution Prevention Workshop scheduled October 4-6, 2006.) and 18th, November 1st, 15th and 29th.

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

Action Items

Welcome and Introductions

Facilitator Alice Shorett convened the conference call at 1:00 PM EST and called the roll of participants. She briefly outlined the agenda and objectives for the call and noted that the bulk of the time would be spent on the prescriptive/descriptive approach, and working toward getting a draft approach for the December FACDQ meeting. Other agenda items were:

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Meeting Summary Review and Approval

The draft summary of the Policy Work Group August 9 meeting was approved as drafted, with a recommended revision for clarification. The one-word clarification agreed upon was for page 4 (Schedule and Work Plan, next to last sentence of the paragraph), whereby the word "group" is changed to "committee", as follows: "It was agreed that there is limited time and that if agreements cannot be reached in December, the committee should move on."

Michael Murray also asked for clarification of what was meant by evaluating the cost associated with using matrices. Mary Smith replied that in some instances it is cost-prohibitive for EPA to account for matrix effects when validating methods.

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Review and Agree on Policy Work Group Schedule and Work Plan

It was agreed that the schedule and work plan would be revised to show the date where specific products need to be finished.

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Prescriptive and Descriptive Approaches

The group was advised to reference the Straw Proposal (June 1, 2006; page 6) as well as the approach circulated by David Kimbrough from the public utility caucus in its considerations for the prescriptive/descriptive approaches.

To begin the discussion, Mary Smith emphasized that EPA is looking for an approach that provides a level playing field and that clearly identifies the bar it is setting for compliance enforcement. From a regulatory standpoint at EPA, the descriptive approach has difficulties. It has inherent flexibilities that make permitting difficult, and it does not provide certainty to facilities for reaching compliance.

Dave Akers noted that EPA's approach to date generally has been prescriptive in setting compliance levels.

Nan Thomey described the needs of the laboratory community. Many of the laboratory clients are doing studies such as treatability in the design of wastewater treatment plants. The laboratories have a need to determine "how low they can go" to detect an analyte, in addition to achieving the regulated level. The reason is that many laboratory clients need the information for engineering studies. Whatever approach is recommended by the FACDQ, it needs to provide flexibility for the laboratories with a companion descriptive approach that can be used for quality assurance/quality control (QA/QC).

Michael Murray described the needs of the environmental community. He said the environmental community needs to go beyond the use in the engineering research studies. For those cases where the WQBEL's are below LQ, he would like to see a move to use the most sensitive methods and to provide incentives for laboratories to use the most sensitive methods.

Larry LaFleur stated that industry wants to have a prescriptive approach of a nationally promulgated quantitation level for use in compliance. He said he could see a descriptive approach for state QA/QC. In talking with his caucus, he said some of their stakeholders see a problem with a table published in a rule.

Alice Shorett asked the group if there was a way, given the needs that are described by representatives of the various caucuses, to craft a hybrid approach, to meet the laboratories' and environmental communities' needs for QA/QC (descriptive) and a nationally promulgated prescriptive approach for compliance thresholds that meets the regulators', industries', and public utilities' needs for a level playing field across the country (prescriptive).

The group discussed the relative merits of the prescriptive/descriptive approaches. Given the different concerns expressed by representatives from Environmental Labs, Environmental Community, Industry and Public Utilities, it was agreed that a hybrid prescriptive/descriptive approach might provide a solution.

Larry LaFleur volunteered to draft a hybrid proposal for discussion at the September 6 Policy Work Group meeting.

Tom Mugan described for the group his "vision" approach that would be carried out descriptively. Results received from individual labs would be fed into a central location and published in a table that would be updated periodically. Mr. Mugan will write up his vision concept for discussion at the Sept. 6 Policy Work Group Meeting. Mary Smith stated that given the legal issues about rule-making, she would consult with the EPA Office of General Counsel about the legalities and flexibilities of the proposed options. It was agreed that the information would be available for the September 6 conference call.

David Kimbrough described the prescriptive approach he circulated (see July 17, 2006, Version B). He stated that all methods would have the same LQ for a given analyte, a detection limit that all instruments and laboratories had to demonstrate they could meet. He noted there was a placeholder for a descriptive approach in his draft "Section 3 - Laboratory Evaluation and Comparison Procedures." This section would be filled in with whatever descriptive approach is decided upon by the FACDQ.

Alice Shorett asked if there were additional comments or questions about the draft circulated by David Kimbrough. Michael Murray requested that Table 1B (List of Approved Inorganic Test Procedures & Measurement Quality Objectives) be revised and simplified to distinguish between Lowest Water Quality Objectives (LWQOs) for the Clean Water Act and the Safe Water Drinking Act. Nan Thomey suggested that a provision be included that defines what to do if a matrix effect prevents a limit from being achieved.

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Uses

Alice Shorett requested the group compare two uses documents (Straw Proposal, June 1, 2006 and Alternate Uses Straw for 7-14 Discussion) for discussion purposes. She reminded the group that the objective is to refine a proposal for the committee to consider in December. Tom Mugan and Dave Akers started by discussing the alternative proposal as presented at the July committee meeting. Ms. Shorett asked that they explain how data would be reported and what it would be used for under each of the steps in the alternative proposal.

After Mr. Akers explained the alternative proposal, the group engaged in a discussion mainly focused on what gets reported on a Discharge Monitoring Report form and how the collection of data below LQ could be separated from compliance and enforcement actions (when the WQBEL is below or near LQ). Some members of the group questioned the notion in #3 of assigning "0" (zero) to detects less than LQ for either calculating averages or daily maximum limits. Dave Akers responded with an example to illustrate the use of zero. If the LQ= 10, and 5 samples were taken with one hit at LQ and 4 below LQ, the average would be 2 and the daily maximum would be 10 (Average: 10+0+0+0+0 / 5 = 2; Daily Max = 10).

With regard to #4, Chris Hornback suggested the words "on, or..." be removed from the first sentence so that information less than LQ would be reported on an attachment to the DMR.

At that point, the group discussed the difficulty in certifying numbers as "true and accurate" on the DMR below LQ, when there is uncertainty around the accuracy of the numbers. If numbers are certified below LQ, the person certifying those numbers cannot later take back the statement that they were "true and accurate." Nan Thomey asked whether it was in the committee's charter to recommend language revisions for certifying a DMR. Larry LaFleur responded that it could be and said that he has some draft language to offer if the committee were interested in pursuing this. The group then discussed the feasibility and logistics of reporting numbers less than LQ on something other than the DMR. There are some real practical database constraints to this approach from the regulators' perspective.

With regard to #5, the committee again discussed the implications this step has on prescriptive versus descriptive approaches. David Kimbrough said there is a concern with a hybrid method in having a prescribed LQ, but allowing for a descriptive LC, because it creates inequity. Larry LaFleur asked whether it was outside the scope of the committee's charter to recommend pollutant minimization programs since it is effectively not a detection or quantitation use. Other members of the group felt it was within the charter and that the states were trying to come up with a compromise approach, specifically in dealing with information reported below LQ (e.g. DNQ).

The group ultimately agreed that steps 4 and 5 in the alternative proposal should be re-written to further clarify the recommendation. Tom Mugan agreed to revise the alternative proposal based on the discussion.

Before closing the meeting, Bob Wheeler commented that the group did not discuss other uses. He asked Larry LaFleur, who had brought this issue up at a previous meeting whether that was still needed for consideration at the next Policy Work Group meeting. Mr. LaFleur suggested that the group did go there, in a sense, by discussing matrix effects and prescriptive/descriptive issues.

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Wrap-up and Closing

The next steps and assignments are outlined as Action Items on page 1 of the meeting summary. Alice Shorett thanked everyone for their participation and concluded the call at 2:30 PM (EDT).

Attendance

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