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All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Radioactive Liquid Waste Treatment Facility Discharges in 2017

This report documents radioactive discharges from the TA50 Radioactive Liquid Waste Treatment Facility (RLWTF) during calendar year 2017. During 2017, all treated water was fed to the effluent evaporator. The evaporator was operated 3574 hours on 224 days, primarily in one-burner mode (63% of the time). A total of 3.42 million liters of treated water were fed to the evaporator, and 3.36 million liters were discharged to the environment as steam from the evaporator stack. Evaporator operation continued the single-tank feed mode that was begun in 2014. Specifically, when a Frac tank was filled with treated water, contents of the tank were mixed; a representative sample was collected; and the sample was analyzed to assess water quality. A total of 49 tanks of treated water were sampled, analyzed, and then fed to the evaporator during 2017. Tank samples were analyzed for gross alpha, gross beta, tritium, and a few inorganic parameters such as nitrate and dissolved solids. Frac tank samples of evaporator feed were held, then composited at the end of each month. Each monthly composite sample was then analyzed for gross alpha, gross beta, tritium, and 36 radioisotopes (eight alpha-emitting isotopes, 28 beta emitters). Samples were also collected of water drained from the evaporator. These samples, analyzed for alpha, beta, and tritium concentrations, were then used to estimate radioactive quantities present in evaporator drain water. The difference, rad fed less rad drained, yielded quantities of radioactivity discharged through the stack into the environment . Table 1 summarizes this information.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

2nd Quarter Transportation Report FY2016: Waste Shipments to and from the Nevada National Security Site (NNSS), Radioactive Waste Management Complex

This report satisfies the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office commitment to prepare a quarterly summary report of waste shipments to and from the Nevada National Security Site (NNSS) Radioactive Waste Management Complex at Area 5. This report summarizes the 2nd quarter of Fiscal Year (FY) 2016 low-level radioactive waste, mixed low-level radioactive waste, and classified non-radioactive shipments. There were no shipments sent for offsite treatment and returned to the NNSS this quarter of FY2016.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Waste Shipments To and From the Nevada National Security Site (NNSS), Radioactive Waste Management Complex (4th Quarter / Annual Transportation Report FY2015)

This report satisfies the National Nuclear Security Administration Nevada Field Office commitment to prepare a quarterly summary report of waste shipments to and from the Nevada National Security Site (NNSS) Radioactive Waste Management Complex at Area 5. This report summarizes the 4th quarter of Fiscal Year (FY) 2015 low-level radioactive waste, mixed low-level radioactive waste shipments and classified non-radioactive shipments. There were no shipments sent for offsite treatment and returned to the NNSS this quarter or during FY 2015.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

4 th Quarter / Annual Transportation Report FY16: Waste Shipments To and From the Nevada National Security Site (NNSS), Radioactive Waste Management Complex

This report satisfies the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office commitment to prepare a quarterly summary report of waste shipments to the Nevada National Security Site (NNSS) Radioactive Waste Management Complex at Area 5. This report summarizes both the 4th quarter and fiscal year (FY) 2016 low-level radioactive waste, mixed low-level radioactive waste, and classified non-radioactive shipments. There were no shipments sent for offsite treatment from a NNSS facility and returned to the NNSS this quarter of FY 2016.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

3rd Quarter Transportation Report FY16: Waste Shipments To and From the Nevada National Security Site (NNSS), Radioactive Waste Management Complex

This report satisfies the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office commitment to prepare a quarterly summary report of waste shipments to the Nevada National Security Site (NNSS) Radioactive Waste Management Complex at Area 5. This report summarizes the 3rd quarter of fiscal year (FY) 2016 low-level radioactive waste, mixed low-level radioactive waste, and classified non-radioactive shipments. There were no shipments sent for offsite treatment from a NNSS facility and returned to the NNSS this quarter of FY2016.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Radioactive Waste Management Basis (Rev.6)

This Radioactive Waste Management Basis (RWMB) documents radioactive waste management practices adopted at Lawrence Livermore National Laboratory (LLNL) pursuant to Department of Energy Order (DOE O) 435.1, Radioactive Waste Management. The purpose of this RWMB is to ensure that LLNL manages radioactive waste in a safe and environmentally-compliant manner, protective of worker and public safety.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Safe and Secure Management of Disused Radioactive Sealed Sources in Egypt - 19063

Radioactive sources offer many benefits in medicine, industry and education but the lack of appropriate long-term management when they eventually become disused has led to accidents, in some cases with serious consequences, and increased their vulnerability for use in a malicious act. This lack is evident in the absence of clearly defined policy and strategy, responsibilities and resources to meet those responsibilities for safe, secure and sustainable management of disused sources. The strengthening of national legislative and regulatory infrastructures globally has led to major improvements in the protection and control of radioactive sources. Nevertheless, in many countries, radioactive sources were in use before such infrastructures had been developed or adequately strengthened and were therefore not under regulatory control. The paper presents some aspects from Egyptian experience related to safe and secure measures for management of Cs-137, Ra-226 and Co-60 sealed sources. Data relating to the disused radioactive sealed sources, DSRS inventory as well as the arrangements made in order to prepare for conditioning of sources is presented. The efforts made by technical staff and radiation protection team for all arrangements and details such as conditioning set-up, working area, leakage test, certified stainless capsules, radiation protection measures and sources characterization in addition to all security measures for stored DSRS are also presented. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Realization of the National Disposal Facility for Radioactive Waste in Bulgaria - 16611

Radioactive waste is generated in the Republic of Bulgaria from the operation and decommissioning of the country's nuclear power plants and from other sources in research, medical applications, and the industry. The need for building a National Disposal Facility (NDF) is recognized by the Bulgarian government and described and justified in its Environment Impact Assessment Decision. The Bulgarian State Enterprise for Radioactive Waste Management (SERAW) is endeavoring to build a near-surface repository for short-lived low- and intermediate-level radioactive waste (SL-LILW) to discharge its statutory responsibilities in waste management is. The European Union (EU) finances the establishment of the NDF through the Kozloduy International Decommissioning Support Fund (KIDSF). After an international tendering procedure, SERAW placed a contract for the development of the design of the NDF to the Consortium of Westinghouse Electric Spain S.A.R and DBE Technology GmbH of Germany, with ENRESA, the Spanish National Waste Management Agency providing technical review and support. Two Bulgarian companies participate also in the project as subcontractors - EQE Bulgaria and to a lesser extent KK-Project. The repository project official name is 'Technical Design and ISAR Preparation for the National Disposal Facility at Bulgaria', usually abbreviated as 'R-Project 5'. After obtaining SERAW's approval for the preferred repository conceptual design variant, the R Project 5 focused on developing the Technical Design on the one hand, and on preparing the Intermediate Safety Analysis Report (ISAR) to demonstrate the safety and suitability of the proposed NDF design on the other. These documents were handed over to the Bulgarian Nuclear Regulatory Authority (BNRA) as well as to the different authorities involved in the comprehensive licensing process required for nuclear facilities in the country. The corresponding permits have mostly been received or are expected for early 2016. In the last quarter of 2015 the procurement procedure for repository construction as turn-key project was started with the pre-qualification of possible constructors for the Phase I repository realization on a lump sum contract basis. Repository construction is now expected to start in 2016, with the start of waste disposal now scheduled for around 2020. With the realization of the Bulgarian National Disposal Facility an important milestone for waste disposal in the European Union is about to be achieved. This paper is a sequel of previously presented papers on the NDF construction, now including details of the complex licensing process that this disposal facility underwent, now in its final stages. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

A Decade of Innovative Approaches to Treating and Dispositioning Radioactive Waste at the Savannah River Site - 20620

This year marks the 70. anniversary of the U.S. Department of Energy's (DOE) Savannah River Site (SRS), located near Aiken, South Carolina. SRS is a key industrial complex responsible for environmental stewardship, environmental cleanup, waste management, and disposition of nuclear materials. SRS also continues to have a role in critical defense-related activities and the reprocessing of used reactor fuel. The SRS encompasses 803 square kilometers (310 square miles) in parts of Aiken, Barnwell, and Allendale counties. The Liquid Waste Mission starts with the safe receipt and storage of radioactive liquid waste in the waste tanks, which principally includes Cold War legacy waste, but also waste from support of National Aeronautics Space Administration missions, medical isotope production, and research activities. This 133,000 cubic meters (m{sup 3}) (35 million gallons [Mgal]) of high-level radioactive waste (HLW) is currently held in 43 large underground waste tanks. The capacity of each of these tanks range from 2,800 m{sup 3} to 5,000 m{sup 3} (0.75 to 1.33 Mgal) and were placed in operation between 1954 and 1986. In July 2009, the DOE awarded a stand-alone contract to execute the Liquid Waste Mission at SRS. The Liquid Waste Contractor selected was Savannah River Remediation LLC1 (SRR), which is responsible for receipt, storage, retrieval and treatment of all HLW, disposal of the decontaminated low-activity waste fraction, as well as operationally closing cleaned HLW tanks. Since July 2009, SRR has successfully grouted and operationally closed six large underground tanks, poured 1,476 canisters of vitrified HLW (a stable glass waste form), treated approximately 34,200 m{sup 3} (9.0 Mgal) of HLW, and dispositioned over 41,200 m{sup 3} (10.9 Mgal) of decontaminated salt solution as low-level waste (LLW) into the Saltstone Disposal Units (SDUs) being constructed by SRR on site. The innovative work performed by SRR in the LLW portion of its mission has earned it the Richard S. Hodes Award. The work conducted by SRR is the same work championed by the late Richard S. Hodes, a respected physician, statesmen, and Chairman of the Southeast Compact Commission for Low-Level Radioactive Waste Management. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Life cycle Management of 324 Project High-Activity, Mixed/Low-Level Radioactive Waste - 20506

U.S. DOE contractor CH2M Hill Plateau Remediation Company (CHPRC) manages the 324 Building and is preparing to remotely excavate and disposition the radioactive soil beneath the building to allow further deactivation of the building. The 324 Building is a non-reactor Category 2 Nuclear Facility located in the 300 Area of the Hanford Site. Records indicate that in October 1986, approximately 516 liters of a concentrated liquid waste stream containing cesium-137 ({sup 137}Cs) and strontium-90 ({sup 90}Sr) spilled onto the floor of a hot cell, B-Cell, in the 324 Building. The spill contained an estimated 1.3 million curies (Ci) of radioactivity. A breach in the sump of B-Cell was discovered in November 2009 during characterization of the soil under the building. Exposure rates in excess of 10,000 R/hr were detected through a system of access pipes installed under the hot cell, and an estimated 1.557 E+05 Ci of {sup 137}Cs and 6.842 E+04 Ci of {sup 90}Sr are in the soil beneath B-Cell. The magnitude of the soil contamination below B-Cell represents one of the most challenging remediation activities in the DOE complex. The objective of CHPRC's 324 Project is to remotely excavate and disposition the highly contaminated soil under the hot cell so building deactivation and stabilization activities can resume. Depending on the volume and radioactivity of contaminated soil under B-Cell, the material will be dispositioned either at the Hanford Site's Environmental Restoration Disposal Facility (ERDF) or in grout monoliths that will be created in the hot cells (A, C and D) next to B-Cell during future building demolition activities. The current project scope includes installing structural supports under the walls of B-Cell and using remotely operated equipment to remove debris from the hot cell, remove debris mixed with grout on the floor, saw through and remove the cell floor and liner, and excavate contaminated soil under B-Cell to a depth of up to 3.66 meters (12 feet). Addition or removal of debris in A-Cell may be required to support B-Cell cleanout and excavation activities. The base approach is to disposition debris and soil bins in the Radiochemical Engineering Cell (REC) monoliths, and subsequently disposition the monoliths during building demolition. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Total Mercury Analysis of Radioactive Waste Containing Multiple Mercury Species

In this work, a direct mercury analyzer (DMA) was used to analyze total mercury in radioactive waste samples containing methylmercury and other forms of mercury including Hg o (elemental) together with inorganic ionic mercury species and complexes. These samples were also analyzed using Cold Vapor Atomic Absorption Spectroscopy (CVAAS) and/or Inductively Coupled Plasma Mass Spectroscopy (ICMS). Comparative statistical evaluation of the results from spike solutions/simulants, liquid radioactive waste samples, and interlaboratory performance test samples demonstrated that the various methods generated accurate and/or equivalent total mercury data and equivalent precision (2σ ± < 20%). Triplicate total mercury analysis of an exemplar radioactive waste resulted in an average value of 54.1 mg/L (as Hg) using CVAAS, 55.1 mg/L using ICPMS and 56.0 mg/L using DMA. A primary advantage of the DMA in a radioactive environment is avoiding multi-step, labor-intensive, time-consuming and waste-producing sample preparation protocols needed for CVAAS and ICPMS. DMA was determined to be the preferred method for measuring total mercury in the Savannah River National Laboratory (SRNL) radioanalytical laboratory based on analytical performance combined with ease of use in a radiological containment unit.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2023

Investigating radioactive negative ion production via double electron capture

The relative cross sections for radioactive negative ion production via double electron capture have been measured for collisions between a 40 keV projectile beam of uranium-238 and potassium vapor. This was performed at the collinear resonance ionization spectroscopy (CRIS) experiment at CERN-ISOLDE and is a step towards measuring the electron affinities (EAs) of elements that cannot be efficiently produced in negative ion sources at radioactive ion beam (RIB) facilities. This includes short-lived radioactive isotopes that have low production quantities and heavy and superheavy elements that systematically have smaller EAs than work functions of available ion source materials. Negative ions are particularly sensitive to electron–electron correlation effects, which make such studies ideal for benchmarking atomic structure models that go beyond the independent particle model. While the EAs of most light elements have been measured, experimental investigations on heavier elements, namely the actinides, remain scarce due to their radioactive nature and production difficulty. By developing negative ion production by charge exchange, we aim to make these studies feasible at RIB facilities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2013

Review of Monte Carlo simulations for backgrounds from radioactivity

For all experiments dealing with the rare event searches (neutrino, dark matter, neutrino-less double-beta decay), the reduction of the radioactive background is one of the most important and difficult tasks. There are basically two types of background, electron recoils and nuclear recoils. The electron recoil background is mostly from the gamma rays through the radioactive decay. The nuclear recoil background is from neutrons from spontaneous fission, (α, n) reactions and muoninduced interactions (spallations, photo-nuclear and hadronic interaction). The external gammas and neutrons from the muons and laboratory environment, can be reduced by operating the detector at deep underground laboratories and by placing active or passive shield materials around the detector. The radioactivity of the detector materials also contributes to the background; in order to reduce it a careful screening campaign is mandatory to select highly radio-pure materials. In this review I present the status of current Monte Carlo simulations aimed to estimate and reproduce the background induced by gamma and neutron radioactivity of the materials and the shield of rare event search experiment. For the electromagnetic background a good level of agreement between the data and the MC simulation has been reached by the XENON100 and EDELWEISS experiments, using the GEANT4 toolkit. For the neutron background, a comparison between the yield of neutrons from spontaneous fission and (α, n) obtained with two dedicated softwares, SOURCES-4A and the one developed by Mei-Zhang-Hime, show a good overall agreement, with total yields within a factor 2 difference. The energy spectra from SOURCES-4A are in general smoother, while those from MZH presents sharp peaks. The neutron propagation through various materials has been studied with two MC codes, GEANT4 and MCNPX, showing a reasonably good agreement, inside 50% discrepancy.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO{sub 3}){sub 4} ⋅ 5H{sub 2}O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

Biochemical process of low level radioactive liquid simulation waste containing detergent

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10{sup −5} Ci/m{sup 3}. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour{sup −1}.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Measurement of natural and {sup 137}Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring {sup 238}U, {sup 232}Th and {sup 40}K isotopes and also that of an artificial isotope {sup 137}Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of {sup 238}U and {sup 232}Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the {sup 40}K are higher than the average worldwide value. A small amount of {sup 137}Cs contamination, which might be caused by the Chernobyl accident, was also detected.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2020

Niche Partitioning of Microbial Communities at an Ancient Vitrified Hillfort: Implications for Vitrified Radioactive Waste Disposal

A pre-Viking era vitrified hillfort, Broborg, provides a habitat analogue for disposed radioactive waste glass and shows strong niche partitioning among the organisms involved in glass alteration. Microbes cannot be eliminated from radioactive waste disposal facilities and the consequences of bio-colonization must be understood. We use Broborg as a model system to inform what microbial processes might influence long-term radioactive waste glass durability by examining anthropogenic glass that has been subjected to bio-colonization for over 1,500 years. Scanning electron microscopy (SEM) images reveal the surficial biofilm structure, and chemical/mineralogy analysis in combination with deoxyribonucleic acid (DNA) sequencing of samples from the vitrified substrate, the adjacent soil, and the general topsoil provide insight into niche partitioning. The ancient glass niche supports a unique microbial community of bacteria, fungi, and protists that manifests the species response to local geochemical and mineralogical conditions. Communities from the geochemical niche associated with the glass are distinct and less diverse than soil communities. The microbiome of the glass and adjacent soil are dominated by lichens, lichen-associated microorganisms, and other epilithic, endolithic, and epigeic organisms. Pseudomonads dominate the prokaryotic communities on the vitrified material, but not the adjacent soil. In contrast, the general topsoil communities are enriched in plant rhizosphere organisms. Taxa associated with vitrification have bio-corrosive properties that could be detrimental to glass durability, including silicate mineral dissolution, extraction of essential elements, secretion of geochemically reactive organic acids, and dissolution induced by improved water retention. However, these stable long-term biofilms also possess a homeostatic function that could limit glass alteration. Overall, this study demonstrates the potential impacts that microbial colonization and niche partitioning can have on glass alteration and subsequent release of radionuclides from a disposal facility for vitrified radioactive waste.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2017

Production of negatively charged radioactive ion beams

Beams of short-lived radioactive nuclei are needed for frontier experimental research in nuclear structure, reactions, and astrophysics. Negatively charged radioactive ion beams have unique advantages and allow for the use of a tandem accelerator for post-acceleration, which can provide the highest beam quality and continuously variable energies. Negative ion beams can be obtained with high intensity and some unique beam purification techniques based on differences in electronegativity and chemical reactivity can be used to provide beams with high purity. This article describes the production of negative radioactive ion beams at the former holifield radioactive ion beam facility at Oak Ridge National Laboratory and at the CERN ISOLDE facility with emphasis on the development of the negative ion sources employed at these two facilities.

07 ISOTOPE AND RADIATION SOURCES↗