scholarly journals Review of the Scientific Understanding of Radioactive Waste at the U.S. DOE Hanford Site

2018 ◽  
Vol 52 (2) ◽  
pp. 381-396 ◽  
Author(s):  
Reid A. Peterson ◽  
Edgar C. Buck ◽  
Jaehun Chun ◽  
Richard C. Daniel ◽  
Daniel L. Herting ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
Scientific Understanding ◽  
Hanford Site ◽  
The U.S

Spiritual Atheist Scientists

2021 ◽  
pp. 76-93
Author(s):  
Elaine Howard Ecklund ◽  
David R. Johnson
Keyword(s):  
Scientific Work ◽  
Scientific Understanding ◽  
Value Systems ◽  
Spiritual Practices ◽  
Religious Traditions ◽  
Personal Wellness ◽  
The World ◽  
The U.S

Spiritual atheists comprise the smallest subset of atheist scientists in the U.S. and U.K. Unlike modernists (who are not spiritual) and culturally religious atheists (who participate in religion), spiritual atheist scientists construct alternative value systems without affiliating with religious traditions. Many cast spirituality in emotional terms of awe and wonder provoked through scientific understanding of the world, while others frame their spirituality in terms of the dimensions of life that cannot be explained through science. Such constructions of spirituality are consequential for secular spiritual practices. For scientists, these involve scientific work itself, morality in relationships, personal wellness practices, and resources for coping with adversity.

Lessons Learned Siting and Successfully Processing U.S. DOE Radioactive Wastes Using a High Throughput Vitrification Process

2003 ◽  
Author(s):  
Robert E. Prince ◽  
Bradley W. Bowan
Keyword(s):  
The United States ◽  
Lessons Learned ◽  
Volume Reduction ◽  
Waste Form ◽  
High Level Waste ◽  
Hanford Site ◽  
High Level ◽  
Low Activity ◽  
The U.S ◽  
Ceramic Melter

This paper describes actual experience applying a technology to achieve volume reduction while producing a stable waste form for low and intermediate level liquid (L/ILW) wastes, and the L/ILW fraction produced from pre-processing of high level wastes. The chief process addressed will be vitrification. The joule-heated ceramic melter vitrification process has been used successfully on a number of waste streams produced by the U.S. Department of Energy (DOE). This paper will address lessons learned in achieving dramatic improvements in process throughput, based on actual pilot and full-scale waste processing experience. Since 1991, Duratek, Inc., and its long-term research partner, the Vitreous State Laboratory of The Catholic University of America, have worked to continuously improve joule heated ceramic melter vitrification technology in support of waste stabilization and disposition in the United States. From 1993 to 1998, under contact to the DOE, the team designed, built, and operated a joule-heated melter (the DuraMelterTM) to process liquid mixed (hazardous/low activity) waste material at the Savannah River Site (SRS) in South Carolina. This melter produced 1,000,000 kilograms of vitrified waste, achieving a volume reduction of approximately 70 percent and ultimately producing a waste form that the U.S. Environmental Protection Agency (EPA) delisted for its hazardous classification. The team built upon its SRS M Area experience to produce state-of-the-art melter technology that will be used at the DOE’s Hanford site in Richland, Washington. Since 1998, the DuraMelterTM has been the reference vitrification technology for processing both the high level waste (HLW) and low activity waste (LAW) fractions of liquid HLW waste from the U.S. DOE’s Hanford site. Process innovations have doubled the throughput and enhanced the ability to handle problem constituents in LAW. This paper provides lessons learned from the operation and testing of two facilities that provide the technology for a vitrification system that will be used in the stabilization of the low level fraction of Hanford’s high level tank wastes.

Justification for Elevated Hydrogen Limits in Risk-Based Radioactive Waste Packages

2005 ◽  
Author(s):  
Russell Wagner
Keyword(s):  
Nuclear Regulatory Commission ◽  
Department Of Energy ◽  
Radioactive Material ◽  
Transportation Safety ◽  
Elevated Concentration ◽  
Type B ◽  
Hanford Site ◽  
Regulatory Commission ◽  
Concentration Limits ◽  
The U.S

The U.S. Nuclear Regulatory Commission (NRC) has provided set guidance that hydrogen concentrations in radioactive material packages be limited to 5 vol% unless the package is designed to withstand a bounding hydrogen deflagration or detonation. The NRC guidance further specifies that the expected shipping time for a package be limited to one-half the time to reach 5 vol% hydrogen. This guidance has presented logistical problems for transport of retrieved legacy waste packages on the Department of Energy (DOE) Hanford Site that frequently contain greater than 5 vol% hydrogen due to their age and the lack of venting requirements at the time they were generated. Such packages do not meet the performance-based criteria for Type B packaging, and are considered risk-based packages. Duratek Technical Services (Duratek) has researched the true risk of hydrogen deflagration and detonation with closed packages, and has developed technical justification for elevated concentration limits of up to 15 vol% hydrogen in risk-based packages when transport is limited to the confines of the Hanford Site. Duratek has presented elevated hydrogen limit justification to the DOE Richland Operations Office and is awaiting approval for incorporation into the Hanford Site Transportation Safety Document. This paper details the technical justification methodology for the elevated hydrogen limits.

Comparative Assessment of Low-Level Radioactive Waste Life-Cycle Disposal Costs of U.S. Commercial Facilities

2001 ◽  
Author(s):  
E. J. Bentz ◽  
C. B. Bentz ◽  
T. D. O’Hora
Keyword(s):  
Life Cycle ◽  
Radioactive Waste ◽  
Life Cycle Cost ◽  
Regulatory Compliance ◽  
Comparative Assessment ◽  
Life Cycle Costs ◽  
Low Level ◽  
Low Level Radioactive Waste ◽  
The U.S ◽  
Total Life

Abstract This paper provides a comparative assessment of low-level radioactive waste (LLW) life-cycle costs for U.S. commercial disposal facilities. This assessment includes both currently operational facilities and planned commercial facilities. After identifying the individual facility’s operational period, current or planned capacity, and historical disposal volumes (where applicable), the paper describes the respective facilities’ waste acceptance criteria, anticipated waste characteristics, and disposal technologies employed. A brief identification of key components of cost categories that constitute life-cycle cost for the disposal facilities is provided, as well as an identification of factors that affect life-cycle cost. A more specific comparison of certain life-cycle cost components for the disposal facilities is provided, with regard to U.S. LLW disposal volumes and characteristics. Similarities and differences in total life-cycle cost and life-cycle category-specific costs among the U.S. facilities are presented and discussed. The data presented reveals that: • No new LLW commercial disposal facilities have been sited in the U.S. since 1988, and that siting of LLW disposal facilities in the U.S. has become increasingly difficult and contentious, necessitating long lead times and significant up-front costs — without any certainty of success. • Overall, life-cycle costs for LLW disposal at U.S. commercial facilities have increased significantly over time, reflecting increased regulatory compliance requirements, state-imposed access fees and taxes, local community hosting incentive costs, and cost escalation inherent in delays in establishing facilities or modifying existing licensed facilities. • Life-cycle costs are also significantly affected by the nature of the engineered isolation technology employed, reflecting the geologic characteristics of the siting location and the activity levels of the wastes accepted. • Since many of the newly-planned facilities anticipate receiving lower total volumes with an increasingly greater percentage of higher activity wastes (than historical volumes disposed) and are to be sited in more ecologically sensitive geologic regions, they will require more comprehensive — and hence more expensive — engineered isolation technologies. As a result, currently planned facilities are anticipated to experience significantly higher total life-cycle costs than existing operational facilities.

Development of a Mechanical Based System for Dry Retrieval of Single-Shell Tank Waste at Hanford

2013 ◽  
Author(s):  
Ximena Prugue
Keyword(s):  
Radioactive Waste ◽  
Gas Release ◽  
Storage Space ◽  
Hanford Site ◽  
The Past ◽  
Waste Storage ◽  
Air Lift ◽  
Surrounding Soil ◽  
Single Shell ◽  
Tank Waste

This study explores the development of a mechanical based system to retrieve single-shell tank waste at the Hanford site, located in Richland, Washington, without the addition of water. Out of 177 tanks at Hanford, there are 149 single-shell tanks (SST) and 28 double-shell tanks (DST). There are currently 67 SSTs that have leaked radioactive waste to the surrounding groundwater in the past or assumed to have questionable tank integrity. Leaking tanks continue to be a major concern as it was recently announced in February 2013 that six SSTs are leaking, even though they were believed to have been stabilized back in 2005. There are also several tanks with significant in-tank obstructions, such as air-lift circulators, where an arm-based retrieval would not be possible. All current methods of waste retrieval deployed involve the addition of significant amounts of water to generate a slurry that can be pumped out of the tank. This water, however, can exacerbate the leak and risk the potential of leaking more waste into the surrounding soil, subsequently contaminating the groundwater. It also reduces available waste storage space in DSTs, and increases the risk of dangerous buoyant displacement gas release events (BDGRE) in the headspace of DSTs. Focusing on leaking tanks, tanks with significant in-tank obstructions, and utilizing existing risers in Hanford’s tanks, this study evaluates commercially available dry technologies, such as augers and high-powered vacuums, for feasibility, safety, and efficiency of waste retrieval at Hanford.

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