Publications

Results 1–25 of 30

Search results

Jump to search filters

Evaluating T2 Conversion to Tritiated Water under Ambient Conditions - Case Study

Takahashi, Lynelle K.; Jarek, Russell L.

In 2015, an incident released approximately 40 Ci of T2 gas directly into the Tritium Exhaust System. Data from a bubbler system that monitored the stack effluent during the time period encompassing the accident, from 9 days prior through approximately 26 hours following the release, indicated that approximately 0.25% of the total accumulated tritium gas was in the form of tritiated water; however this value does not account for sources of tritium exhaust from other building operations and processes during the 9 days prior to this incident. Further analysis of the bubbler data around this time period considered the 9-day background contributions and shows that the actual fraction of the tritium that was released as tritiated water vapor (during and within 26 hours after the release) was likely lower than 0.1%.

More Details
TYPE Other Report YEAR 2020
DOIOSTI

Analysis of Gas Samples Taken from the High Burnup Demonstration Cask

Bryan, Charles R.; Jarek, Russell L.; Flores, Christopher; Leonard, Elliott J.

The High Burn-Up Demonstration Project was recently initiated by the Department of Energy (DOE) to evaluate the effects of fuel drying and long term dry storage on high burn-up spent nuclear fuel. As part of the project, samples of the He backfill gas were collected 5 hours, 5 days, and 12 days after completion of drying. The samples provide information on the state of the fuel at closure, and on the environment within the cask. At Sandia National Laboratories, the samples were analyzed by gamma-ray spectroscopy to quantify fission product gases and by gas mass spectrometry to quantify bulk and trace gases; water content was measured via humidity probe. Gamma-ray spectroscopy results indicated no detectible 85Kr, indicating no failed fuel rods were present after drying. Mass spectrometry indicated build-up of CO2 to 930 ppmv over two weeks, attributed to oxidation of organic compounds (possibly vacuum grease or vacuum pump oil) within the cask. H2, generated by either radiolysis or metal corrosion, also increased up to —500 ppmv. Water contents in the cask were higher than anticipated, increasing to —17,400 ppmv ±10% after 12 days. Measuring water content proved challenging, and possible improvements to the method for future analyses are proposed.

More Details
TYPE SAND Report YEAR 2019
DOIOSTI

Analysis of gas samples collected from the DOE high burn-up demonstration cask

International High-Level Radioactive Waste Management 2019, IHLRWM 2019

Bryan, Charles R.; Jarek, Russell L.; Flores, Christopher; Leonard, Elliott J.

The DOE and industry collaborators have initiated the high burn-up demonstration project to evaluate the effects of drying and long-term dry storage on high burn-up fuel. Fuel was transferred to a dry storage cask, which was then dried using standard industry vacuum-drying techniques and placed on a storage pad to be opened and the fuel examined in 10 years. Helium fill gas samples were collected 5 hours, 5 days, and 12 days after closure. The samples were analyzed for fission gases (85Kr) as an indicator of damaged or leaking rods, and then analyzed to determine water content and concentrations of other trace gases. Gamma-ray spectroscopy found no detectible 85Kr. Sample water contents proved difficult to measure, requiring heating to desorb water from the inner surface of the sampling bottles. Final results indicated that water in the cask gas phase built up over 12 days to 17,400 ppmv ±10%, equivalent to ∼100 ml of water within the cask gas phase. Trace gases were measured by direct gas mass spectrometry. Carbon dioxide built up over two weeks to 930 ppmv, likely due to breakdown of hydrocarbon contaminants (possibly vacuum pump oil) in the cask. Hydrogen built up to nearly 500 ppmv. and may be attributable to water radiolysis and/or to metal corrosion in the cask.

More Details
TYPE Conference Poster YEAR 2019
OSTIScopus

Overview of Total System Model Used for the 2008 Performance Assessment for the Proposed High-Level Radioactive Waste Repository at Yucca Mountain Nevada

Proposed for publication in Reliability Engineering and System Safety.

Hansen, Clifford H.; Olszewska-Wasiolek, Maryla A.; Bryan, Charles R.; Hardin, Ernest H.; Jarek, Russell L.; Mariner, Paul M.; Mattie, Patrick D.; Sassani, David C.; Sevougian, Stephen D.; Stein, Joshua S.

Abstract not provided.

More Details
TYPE Journal Article YEAR 2013
OSTI
Results 1–25 of 30
Results 1–25 of 30