skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An experimental approach to determining subsurface leakage from a surface impoundment using a radioisotope tracer

Conference ·
OSTI ID:6001245

Bromine-82, a 35.3-h half-life radionuclide, was used as a tracer to determine the paths and rates of leakage from an unlined, 1,000,000-gal (3,785,000 L), surface impoundment at the Oak Ridge National Laboratory. Since the impoundment is underlain and surrounded by storm sewer and sanitary sewer lines (most of them predating the impoundment), known and suspected leak sites in storm drain catch basins and sanitary sewer manholes were sampled periodically and analyzed for /sup 82/Br. A series of four ground water monitoring wells - three downgradient and one upgradient from the impoundment - were also sampled for /sup 82/Br. Although the catch basin and manhole samples picked up /sup 82/Br in leakage from the impoundment less than 5 h after application of the tracer, the monitoring well samples did not contain detectable levels of the radionuclide. It was concluded that the monitoring wells were sampling groundwater moving through the formation, whereas the storm drains and manholes were sampling water leading rapidly through secondary porosity and along preferred pathways. The decline in tracer concentration as a function of time was used to determine the residence time of water in the pond and hence the flow rate through the pond. This flow rate, when compared with the known outflow rate, indicated that the leakage flow was small. Hence, the main value of the test was to identify rapid leakage pathways. The experiment demonstrates the need for sampling subsurface drain systems as part of an integrated monitoring system for leak detection. The effectiveness of /sup 82/Br as a tracer for rapid leaks was also shown.

Research Organization:
Oak Ridge National Lab., TN (USA)
DOE Contract Number:
AC05-84OR21400
OSTI ID:
6001245
Report Number(s):
CONF-8709141-1; ON: DE87014784; TRN: 87-039074
Resource Relation:
Conference: International Atomic Energy Agency research coordination meeting, Oak Ridge, TN, USA, 7 Sep 1987; Other Information: Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English