NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82. 

1608 SPRING HILL ROAD, SUITE 400 • VIENNA, VIRGINIA • 22182 • 703.893.6600 • FAX 703.821.8236 

MEMO 

TO: Weldon Spring Work Group 

FROM: Ron Buchanan, SC&A 

DATE: July 9, 2012 

SUBJECT: Potential Drying of Weldon Spring Pits 

 

During the recent June 2012 Weldon Spring Work Group meeting, the potential of the raffinate 

pits drying out and causing airborne contamination was discussed. The following is a summary 

of this issue. 

Two articles (May 27, 1988, Raffinate Pit Sampling Plan and September 1989 EPA 

Environmental Impact Statement) make reference to the fact that Pits #1 and #2 sometimes 

become dry in the hot summer months, while a report by National Lead Company of Ohio (NLO 

1977) states that even during prolonged dry periods, the inherent consistency of the raffinate 

residue preclude the drying out of the surfaces of the pits. If conditions did exist where the pit 

surfaces dried out and the dust became airborne, this could create an environmental intake of 

radioactive materials that would not be readily related to uranium bioassay, or air sample results, 

by using a ratio method. This would be of particular concern for Pits #1 and #2 for 

environmental Th-230, as Th-230 intake would be determined by using the uranium-to-thorium 

ratio. Because of the time period of use, Th-232 would be restricted to Pits #3 and #4, for which 

there were no indications that these pits dried out. 

Portions of the 1988 (4 pages included) and 1989 (3 pages included) articles are attached. 

Reference: 

NLO 1977. Study of Radioactive Waste Storage Areas at ERDA – Weldon Spring Site, NLCO1144 (Special). National Lead Company of Ohio under Contract No. EY-76-C-05-1156, United 

States Energy Research and Development Administration, Oak Ridge Operations Office. April 

25, 1977 (SRDB Ref ID #3583). Republished August, 1981 (SRDB Ref ID #3576).
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.
NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.