Corrosion of Candidate Container Materials in Air-Steam Mixtures

1987 ◽  
Vol 112 ◽  
Author(s):  
James M. Lutton ◽  
D. A. Dewees ◽  
C. G. Robinson ◽  
W. F. Brehm ◽  
R. P. Anantatmula
Keyword(s):  
Carbon Steel ◽  
Nuclear Waste Repository ◽  
Corrosion Mechanism ◽  
Ferritic Alloy ◽  
Corrosion Rates ◽  
Air Atmosphere ◽  
Base Materials ◽  
High Level Nuclear Waste ◽  
High Level ◽  
Corrosion Of Iron

AbstractThe environment during the operating period of a high-level nuclear waste repository in basalt is expected to be air saturated with steam. Liquid groundwater is not expected to be in contact with the container surface during that time.The report presents corrosion findings from tests conducted for one to twenty-five months in an air-steam environment. Tests were carried out with bare metal specimens exposed to an air atmosphere containing 12% moisture in chambers maintained at temperatures between 150°C and 300°C. Cast carbon steel exhibited total penetrations less than 0.002 mm for exposures up to 25 months. A ferritic alloy steel, Fe9CrlMo, showed corrosion results very similar to cast carbon steel. Unalloyed copper materials showed essentially linear corrosion rates, with total penetrations between 0.002 mm at 150°C and 0.14 mm at 300°C in 25 months. Cupronickel 90−10 exhibited total penetrations between 0.001 mm at 150°C and 0.05 mm at 300°C in 25 months. There was a tendency for the corrosion rate to increase with time for cupronickel at 250°C and 300°C possibly because of a mid-test change in the corrosion mechanism. Limited testing of specimens surrounded with bentonite/basalt packing material indicated that the presence of packing has no strong effect on the corrosion of iron-base materials; however, copper-base and cupronickel materials corroded at higher rates in the presence of packing, with a possible shift towards the lower bare specimen corrosion rates with increasing time.

Mcc Corrosion Tests at Reference Testing Conditions for A27 Cast steel in Hanford Ground Water

1986 ◽  
Vol 84 ◽  
Author(s):  
M.D. Merz ◽  
F. Gerber ◽  
R. Wang
Keyword(s):  
Pacific Northwest ◽  
Pressure Vessel ◽  
Static Pressure ◽  
Cast Steel ◽  
Statistical Treatment ◽  
Testing Conditions ◽  
Corrosion Tests ◽  
Corrosion Rates ◽  
High Level Nuclear Waste ◽  
High Level

AbstractThe Materials Characterization Center (MCC) at Pacific Northwest Lab- oratory is performing three kinds of corrosion tests for the Basalt Waste Isolation Project (BWIP) to establish the interlaboratory reproducibility and uncertainty of corrosion rates of container materials for high-level nuclear waste. The three types of corrosion tests were selected to address two distinct conditions that are expected in a repository constructed in basalt. An air/steam test is designed to address corrosion during the operational period and static pressure vessel and flowby tests are designed to address corrosion under conditions that bound the condi ring the post-closure period of the repository.The results of tests at reference testing conditions, which were defined to facilitate interlaboratory comparison of data, are presented. Data are reported for the BWIP/MCC-105.5 Air/Steam Test, BWIP/MCC-105.1 Static Pressure Vessel, and BWIP/MC-105.4 Flowby Test. In those cases where data are available from a second laboratory, a statistical analysis of interlaboratory results is reported and expected confidence intervals for mean corrosion rates are given. Other statistical treatment of data include analyses of the effects of vessel-to-vessel variations, test capsule variations for the flowby test, and oven-to-oven variations for air/steam tests.

Conductivity Behavior of Salt Deposits on the Surface of Engineered Barrier Materials for the Potential High-Level Nuclear Waste Repository at Yucca Mountain, Nevada

2004 ◽  
Vol 824 ◽  
Author(s):  
Lietai Yang ◽  
Miriam R. Juckett ◽  
Roberto T. Pabalan
Keyword(s):  
Electrical Conductance ◽  
Yucca Mountain ◽  
Nuclear Waste Repository ◽  
Conductivity Measurements ◽  
Barrier Materials ◽  
Salt Mixtures ◽  
High Level Nuclear Waste ◽  
Waste Repository ◽  
High Level ◽  
Conductivity Behavior

AbstractThe electrical conductance or conductivity of three salt mixtures, Na-K-Cl-NO3, Ca-K-Cl and Ca-Na-Cl, were measured at 25, 50 and 70°C [77, 122, and 158 °F] as a function of relative humidity (RH). Mutual deliquescence and efflorescence RH (MDRH and MERH) values were determined based on the conductivity measurements. It was found that the conductivity of the three salt mixtures started to increase at RH values that are approximately 40 % of their MDRH and increased by 1to 2 orders of magnitude just before reaching the MDRH. At the MDRH, a significant increase in conductivity was observed. The MDRH and MERH for the Ca-K-Cl and Ca-Na-Cl mixtures were found to be approximately 15 % in the temperature range of 50 to 70 °C [122 to 158 °F]. The MDRH and MERH for the Na-K-Cl-NO3system were found to be approximately 54 % at 50 °C [122 °F] and decreased significantly with an increase in temperature.

Microearthquakes at Yucca Mountain, Nevada

1992 ◽  
Vol 82 (1) ◽  
pp. 164-174
Author(s):  
James N. Brune ◽  
Walter Nicks ◽  
Arturo Aburto
Keyword(s):  
Great Basin ◽  
Narrow Band ◽  
High Gain ◽  
Yucca Mountain ◽  
Continuous Operation ◽  
Nuclear Waste Repository ◽  
High Level Nuclear Waste ◽  
Waste Repository ◽  
High Level ◽  
Approximate Magnitude

Abstract We operated a microearthquake array in the neighborhood of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada. The array consists of four high-gain (up to 34 million), narrow band (25 Hz) telemetered stations. Based on approximate magnitude calibration of the array we expect during quiet periods, for distances less than 15 km, complete recording of events at Yucca Mt. for M ≧ −1. We have operated the four stations for 12-hour periods overnight between August and October 1990 and intermittently afterward, until April 1991, when we began more or less continuous operation. The pattern of microearthquake activity confirms the existence of a zone of seismic quiescence in the vicinity of proposed repository. We recorded only about 10 events with S-P times of less than 3 sec (D < 24 km). Most events had S-P times between 3 and 6.5 sec, consistent with the higher seismic activity at distances between 24 and 52 km observed by Rogers et al. (1987) and Gomberg (1991). Oliver et al. (1966) found, contrary to what has been observed by us for Yucca Mountain, that in seismically active areas most of the events had S-P times of less than 3 sec. We confirmed this expectation for four microearthquake stations near Mammoth Lakes, where we observed microearthquake rates of over 100 per day, most with S-P times of less than 3 sec. Extrapolation of seismicity data from the Southern Great Basin Seismic Network confirms the low microearthquake activity in the immediate vicinity of Yucca Mountain.

Total System Performance Assessment Model for the Final Environmental Impact Statement for the Potential High-Level Nuclear Waste Repository at Yucca Mountain

2002 ◽  
Author(s):  
George J. Saulnier ◽  
K. Patrick Lee ◽  
Donald A. Kalinich ◽  
S. David Sevougian ◽  
Jerry A. McNeish
Keyword(s):  
System Performance ◽  
Transport Model ◽  
Yucca Mountain ◽  
Nuclear Waste Repository ◽  
Total System ◽  
Operating Modes ◽  
Final Rule ◽  
High Level Nuclear Waste ◽  
High Level ◽  
Component Models

The total-system performance assessment (TSPA) model for the final environmental impact statement (FEIS) for the potential high-level nuclear-waste repository at Yucca Mountain, Nevada was developed from a series of analyses and model studies of the Yucca Mountain site. The U.S. Department of Energy (DOE) has recommended the Yucca Mountain, Nevada site for the potential development of a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. In May 2001, the DOE released the Yucca Mountain Science and Engineering Report (S&ER) for public review and comment. The S&ER summarizes more than 20 years of scientific and engineering studies supporting the site recommendation (SR). Following internal reviews of the S&ER and other documents, the DOE performed supplemental analyses of uncertainty in support of the SR as summarized in the Supplemental Science and Performance Analysis (SSPA) reports [2, 3]. The SSPA (1) provided insights into the impact of new scientific data and improved models and (2) evaluated a range of thermal operating modes and their effect on the predicted performance of a potential repository. The various updated component models for the SSPA resulted in a modified TSPA model, referred to as the supplemental TSPA model or SSPA TSPA model capturing the combined effects of the alternative model representations on system performance. The SSPA TSPA model was the basis for analyses for the FEIS for the Yucca Mountain site. However, after completion of the SSPA, the U.S. Environmental Protection Agency (EPA) released its final radiation-protection standards for the potential repository at Yucca Mountain (40 CFR Part 197). Compliance with the regulation required modification of several of the component models (e.g., the biosphere transport model and the saturated-zone transport model) in order to evaluate repository performance against the new standards. These changes were incorporated into the SSPA TSPA model. The resulting FEIS TSPA model, known as the “integrated TSPA model,” was used to perform the calculations presented in this report. The results of calculations using the FEIS TSPA model under a non-disruptive scenario, show that the potential disposal of commercial and DOE waste at a Yucca Mountain repository would not produce releases to the environment that would exceed the regulatory standards promulgated in the EPA Final Rule 10 CFR 197 and the NRC Final Rule 10 CFR 63 for both individual protection and groundwater protection. The analyses also show that both the high and low-temperature operating modes result in similar mean annual dose to the reasonably maximally exposed individual (RMEI). Further, the analyses show that consideration of intrusive and extrusive igneous events, human intrusion, or inclusion of the potential inventory of all radioactive material in the commercial and DOE inventory would not exceed those published standards.

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