The meeting was held at the CSSA Building One conference room, beginning at 1000 hours on April 7, 1997.  This meeting was attended by representatives of CSSA, AFCEE, and Parsons ES.  The following were in attendance (see attached sign-in sheet for TIM No. 6 meeting attendees):

Meeting Purpose

The purpose of the meeting was to discuss issues relative to the background metals study, review outstanding issues, and to update AFCEE and CSSA on the project status to date.

Meeting Agenda

The agenda was as follows:

·        Background metals study issues to be resolved (see attached list)

·        Comments on draft Field Effort 1 reports

·        Project status to date

Issues to be resolved

1.         Grouping of data: 

A.  Soil and rock types:  Brackett, Brackett-Tarrant, Glen Rose, etc. (9 total)

B.  Soil, Rock (2 total) (Comments G1, G4)

       The TNRCC is comfortable with the approach of grouping data.  Drew Rak and Beth Garland of AFCEE/ERC would like to see comparable data.  If the existing data sets can be combined, then we will leave the soil data as is.  If we cannot do this, then we will combine data as soil/rock.  A decision was made to stick with nine soil types and one rock type.

2.    Non-detect data values to be used: 

A.   Terra Lab’s MDLs

1) AFCEE PQLs for appropriate method (Chemistry comment G2)

2) Two times Terra’s MDLs

B.   Other lab’s SQLs

1) Actual SQLs

2) AFCEE PQLs

       A decision was made to use one-half the current AFCEE PQLs.  Drew Rak said to note in the report text that though SQLs are preferred, they are not available for all three data sets.

3.          Statistical approach: 

       A.  <50% Non-detect

1) Test for normality of each data set, determine 95% UTL of appropriate data set

2) Determine 95% UTL of log transformed data set (Comment G5)

       The group had a discussion regarding the approach for <50% NDs:  test for normality and then do 95% UTL on appropriate data set, or just assume lognormal distribution (use lognormal data for 95% UTL).  It was decided that AFCEE will provide justification to assume lognormal distribution, and Parsons ES is to revise the calculations accordingly.  Parsons will put together a draft letter to notify TNRCC that revisions to background report are coming.  Table 4.2 will be e-mailed to Drew Rak.

B.   Adjustments

1) Cohen’s adjustment (even with different SQLs)

2) Alternate adjustment? (Comment S6)

       Question is moot because all SQLs were the same.  Therefore, Cohen’s adjustment is appropriate.

C.   > 50% Non-detect (Comments G3, S9)

1) Remove NDs that had SQLs (greater than 2x the highest hit)

2) If all NDs, either:

a) Conclude that we can’t do a comparison because, without any hits, we don’t know background.

b) Identify highest ND value as background.

       For the submitted draft, if there were >50% NDs, we picked the highest hit as a conservative approach.  In light of a changed approach, we will review the results of the planned revisions to the statistical calculations.

4.    Drew Rak’s Comments 10 and 11:

       Questions were raised regarding higher MS/MSD results.  Data sample results SS-60 were requested to be sent to Beth Garland for review.  Another question raised was whether or to keep “outliers” in data set or remove them.  Drew Rak recommended to leave them in from a statistical viewpoint.  From a chemistry standpoint, Beth Garland needs to review data package pertaining to outliers. 

5.    Beth Garland’s Comment 3:

       A decision was made to use the “F” as values (rather than NDs).

Discussion of AFCEE Comments on Draft Field Effort 1 Reports

Comment 4:

       The comments recommended referencing the [field effort 1] ITIR.  We all agreed that the final field effort 1 ITIR is not correct regarding moisture correction and background numbers.  Jo Jean Mullen will wait to answer what to do with this comment until she reviews tables which Susan Roberts will fax to her.  Note:  tables should contain only “hits”.  However for several sites where there were no hits, e.g. explosives, metals should not be listed out, just indicate that metals = “Not detected.”

Comment 7:

       ITIR reference in the revised background report will be updated per Comment 4’s final outcome.

Comment 9:

       Jo Jean Mullen is interested in the fact that when using data to compare and using data from different labs, there is nothing in the report that there were data from three labs.  May be a moot point because background report will be revised.

Comment 12:

       A reference can be added that comes straight from the regulations.  The information is to be faxed to Jo Jean Mullen.  This had to do with the data we had, probably a comparison to background metals last summer prior to background report revisions.

Project Status

A handout was provided of the weekly update.  Further discussion of AMC RL17 status was not considered necessary.  Regarding AFCEE D.O. 0023, Brian Murphy requested that Susan Roberts contact David Laughlin of TNRCC to discuss any outstanding well upgrade questions.

Action Items

Parsons ES

1.         Provide a response to Andrew Rak’s comments (attached to this minutes).

2.         Prepare a draft letter to notify TNRCC that revisions to background report are coming, and submit as draft to AFCEE and CSSA.

3.         E-mail Table 4.2 of the draft revised background report to Drew Rak.

4.         Mail the data sample results SS-60 to Beth Garland for review.

5.         Submit updated draft background tables for AFCEE and CSSA review and approval by 14 April 97.

6.         Fax draft SWMU closure data tables to Jo Mullen for further discussion.

7.         Fax information regarding draft SWMU Closure Reports Comment 12 to Jo Jean Mullen.

8.         Set up a teleconference with AFCEE and CSSA to resolve any outstanding issues with the updated revisions to the background report and with the draft SWMU closure reports to be submitted after the background changes are approved.

AFCEE/BAH

1.      Review draft TIM No. 7 meeting minutes and provide comments as necessary.

2.      Drew Rak to provide information regarding justification for use of lognormal data sets as standard default.

3.      Participate in teleconference regarding response to draft closure reports, to be scheduled by Parsons ES for May 1997.

4.      Provide review comments as necessary for updated draft revisions to background metals study, to be submitted by Parsons ES on 14 April 97.

CSSA

1.      Review draft TIM No. 7 meeting minutes and provide comments as necessary.