Date:  January 19, 1999
To:     LBNL Tritium Issues Workgroup
Subject:  Status report: Ambient air monitoring split sampling results for 10/6/97 to 9/1/98

Please note that the work reported here is performed as part of the EPA NESHAP program and does not reflect the concurrence of the Tritium Issues Workgroup.

The two attached pages contain the results to date of the analyses of the split silica gel samples EPA has been collecting from the ambient air tritium monitors at the Lawrence Hall of Science (LHS), stations ENV-LHS and ENV-13D. The second column from the right, "Total pCi", indicates the tritium activity in that split sample. We have not yet divided those values by the volumetric air flow through the sample, to calculate an actual air concentration. However, for reference purposes, if one assumed a 100 milliliter/minute flow through the monitor for 30 days, 100 pCi/m3 would correspond to a "total pCi" of 216.0. The NESHAP Table 2 value for "Concentration Levels for Environmental Compliance" that demonstrates compliance with the NESHAP 10mrem/year standard is 1,500 pCi/m3 which would correspond with a "total pCi" of 3,240. This is summarized in the table:

The data indicate that ambient air concentrations have been far below the NESHAP standard, in accordance with the CAP-88 computer modelling results. Preliminary comparisons (not presented here) with the results from LBNL’s contractor indicate reasonable agreement.

This report is preliminary. A "final" status report will contain the EPA calculated ambient air concentration and a discussion of the data as it relates to work performed during the collection periods.

Our split sampling is continuing and we expect to report results quarterly.

Sincerely,

Shelly Rosenblum

attachment
(note made 3/9/99: attachment not available in digital form)