TO: Dr. Jairus D. Flora and Other Interested Parties

FROM: Curt D. Johnson, Chairperson National Work Group on Leak Detection Evaluations (NWGLDE)

SUBJECT: NWGLDE's June 13, 1996 Memo

The National Work Group on Leak Detection Evaluations officially rescinded the subject June 13, 1996 memo during our September 11 and 12, 1997 meeting. Midwest Research Institute's "Evaluation Protocol for Continous In-Tank Leak Detection Methods" dated April 7, 1995 is currently listed as an "Acceptable Test Protocol" on our third edition "List of Leak Detection Evaluations for Underground Storage Tank (UST) Systems" dated April 18, 1997.

Methods that have been, or are going to be evaluated using this protocol will not need to perform third party tests in accordance with the NWGLDE field testing provisions outlined in our June 13, 1996 memo. Instead, third party evaluations may be performed in strict accordance with the MRI or other acceptable protocols and submitted to the NWGLDE for review. If the method is properly evaluated and the test results indicate that the method will meet EPA performance standards, the method will be placed on the NWGLDE list.

The NWGLDE's mission is to review procedures. The NWGLDE now believes that the course of action taken on June 13, 1996 exceeded the Work Group's mission. The NWGLDE's proper course of action should have been to consider only the following four alternatives:

1. Convince the author of the protocol to add the NWGLDE field testing requirements to the protocol.
2. Allow a modification of the proposed NWGLDE field testing to be added to the protocol.

3. Determine the protocol to be unacceptable due to inadequate field testing requirements.
4. Allow the protocol author an oppotunity to convince the NWGLDE that the field testing proposed by the Work Group is not necessary to adequately challenge the methods evaluated.

The NWGLDE decision to rescind our June 13,1996 memo is based on the fourth course of action listed above.