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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Trace Contaminant Control During the International Space Station's On-Orbit Assembly and Outfitting

During the International Space Station’s (ISS’s) on-orbit assembly and outfitting, a series of engineering analyses was conducted to evaluate how effective the passive trace contaminant control (TCC) methods were relative to providing adequate operational margin for the active TCC equipment’s capabilities aboard the ISS. These analyses were based on habitable module and cargo vehicle offgassing test results. The offgassing test for the fully assembled module or cargo vehicle is an important preflight spacecraft evaluation method that has been used successfully during all crewed spacecraft programs to provide insight into how effectively the passive contamination control methods limit the equipment offgassing component of the overall trace contaminant generation load. The progression of TCC assessments beginning in 1998 with the ISS’s first habitable element launch and continuing through the final pressurized element’s arrival in 2010 are presented. Early cargo vehicle flight assessments between 2008 and 2011 are also presented as well as a discussion on predictive methods for assessing cargo via a purely analytical technique.

Contamination control↗
NASA NTRSDate not supplied

Study of Fallout Metrics for Contamination Analysis

A challenge present in assessing contamination accumulation on many missions is predicting fallout during ground processing given the multiple and various orientations possible for surfaces such as optics and instruments. The best practice assumption has been to quantify particle build up on vertical surfaces as approximately 1/10 that of horizontal surfaces. This fractional relation is important when considering contamination allocations necessary to meet cleanliness requirements since spacecraft can be in many orientations during integration and testing. There is insufficient data to provide confidence in the 1/10 approximation, yet its use can have a significant effect on mission end of life contamination level predictions, leading to expenditures of precious resources to meet mission requirements. A study was conducted to compare and analyze the fallout in horizontal and vertical orientations. Silicon wafers were deployed in four different facilities. Data sets from a long term deployment of wafers were analyzed from a cleanroom facility housing integration of the James Webb Space Telescope (JWST) as well as from a shorter term deployment of wafers in three cleanroom facilities at Goddard Space Flight Center with lower activity. There are many variables influencing the relationship between fallout on vertical and horizontal wafers, including wafer position with respect to air flow, air changes in the facility, duration of exposure, and activity workload. The goal of this continuing study is to develop a tool to inform particulate accumulation predictions for future projects.

Contamination↗
NASA NTRS2019

Automated Classification of Transient Contamination in Stationary Acoustic Data

An automated procedure for the classification of transient contamination of stationary acoustic data is proposed and analyzed. The procedure requires the assumption that the stationary acoustic data of interest can be modeled as a band-limited, Gaussian random process. It also requires that the transient contamination be of higher variance than the acoustic data of interest. When these assumptions are satisfied, it is a blind separation procedure, aside from the initial input specifying how to subdivide the time series of interest. No a priori threshold criterion is required. Simulation results show that for a sufficient number of blocks, the method performs well, as long as the occasional false positive or false negative is acceptable. The effectiveness of the procedure is demonstrated with an application to experimental wind tunnel acoustic test data which are contaminated by hydrodynamic gusts.

binary classification↗
NASA NTRSDate not supplied

Propulsive Trajectory Optimization to Minimize Surface Contamination

Descent retroburns using hydrazine thrusters will generate contaminants in their exhaust that can alter underlying samples, such as water-rich surfaces coinciding with possible life signatures or other science measurements of interest. We present an optimization technique that aims to autonomously minimize contamination during surface approach and landing for propulsive vehicles. In addition to short-range hoppers, the optimization technique is also fully applicable to traditional orbit-to-surface landers. This study addresses scenarios where surface alterations from propulsion events are counterproductive or hazardous to the mission objectives. This is of interest for landers (whether human or robotic), that may rely on pristine soils collected in the immediate vicinity of landing sites to accomplish science investigations, mining, or In Situ Resource Utilization (ISRU) surface operations. Such missions are averse to various surface-plume interactions such as thermal scoring, physical agitation, and contamination. The capability can be applied with minimal impact to the baseline concept.

Plume↗
NASA NTRS2022

Environmental Testing of Contamination Sensitive Instruments and Optics in Non-Cleanliness Controlled Facilities

The James Webb Space Telescope (JWST) Optical Telescope Element + Integrated Science Instrument Module (OTIS) went through environmental testing at the Goddard Space Flight Center. The vibration and acoustic tests occurred outside of cleanrooms. These areas are typically around ISO Class 8, far out of specifications for JWST. Through collaboration between the OTIS Mechanical and Contamination Engineering teams, a portable clean enclosure was designed, built, and verified to prevent contamination of the sensitive OTIS assembly. This manuscript describes the process of designing and building this enclosure, including materials selection and High Efficiency Particle Air (HEPA) filtration. This enclosure also provided environmental control with a portable air conditioning unit to control the relative humidity level enabling personnel to work within it. The manuscript emphasizes working in a systematic order to maintain cleanliness and integrity. “Clean as you go” during construction was a top priority to ensure that this critical Ground Support Equipment (GSE) was acceptable. The process of installing the walls and then sealing their internal and external surfaces with approved films was critical to maintaining OTIS integrity. This proved important because OTIS was in the enclosure for months longer than originally planned. This manuscript concludes by reviewing the process used to verify that the OTIS clean enclosure could achieve acceptable contamination level fallout accumulation for use during the vibration and acoustic testing and then verifying that the predicted performance was achieved after testing was complete.

Contamination Control, James Webb Space Telescope,↗
NASA NTRS2022

NASA Engineering and Safety Center Technical Bulletin No. 22-08; Contaminant Reduction in High Purity Hydrazine

Hydrazine and its derivatives are used ubiquitously in liquid propulsion systems. In smaller thruster systems, contaminant build up has historically caused flow decay and consequently performance losses. Many of these contaminants are not controlled by the current revision of MIL-PRF-26536 [1], the High Purity Hydrazine (HPH) procurement specification, yet have been observed to be present in HPH at variable concentration and, often exceed potentially problematic levels for small thrusters. This technical bulletin outlines recent work aimed at identifying appropriate separation processes to remove specific target elemental and carbonaceous contamination in HPH.

Technical Bulletin No. 22-08↗
DOE OSTI2018

3D Time-Lapse Geophysical Imaging Evaluation of Contaminant Migration at the Hanford BY Cribs Site

Changes in bulk electrical conductivity are governed in large part by two diagnostic parameters concerning the state of vadose zone contamination: saturation and pore fluid conductivity. As a robust, remote, non-invasive, three-dimensional, and scalable imaging tool, time-lapse electrical resistivity tomography (ERT) can provide extensive diagnostic information concerning vadose zone contaminant distribution and migration by imaging changes in bulk electrical conductivity. We demonstrate long-term surface ERT monitoring of a ~70-m-thick contaminated vadose zone to investigate whether rising groundwater nitrate levels are caused by unanticipated vadose zone flux. A three-dimensional time-lapse image spanning 10 years (2007-2017) reveals the impacts of meteoric surface infiltration events, but ultimately supports the adequacy of current conceptual understanding by indicating that rising nitrate levels are not sourced in the vadose zone.

resisitivity, geophysics, contamination, monitorin↗
DOE OSTI2017

Integrated Wash-Aid, Treatment, and Emergency Reuse System (IWATERS) for Strontium Contaminations - 17390

The Integrated Wash-Aid, Treatment, and Emergency Reuse System (IWATERS) is being developed to mitigate the release of radioactivity to the urban environment by disseminating, collecting, and processing decontamination wash water. Previously, IWATERS was designed for the treatment of surfaces contaminated with radioactive cesium. Experiments were performed to investigate the expansion of IWATERS for strontium contamination. Bench-scale tests were performed to investigate various counter-ions and chelators to promote ion exchange of strontium from building surfaces. Desorption results for Cs, Sr, and Eu from concrete aggregate and concrete, brick, and asphalt coupons using low- and high-pressure flow with Ca{sup 2+} and Ba{sup 2+} rich wash water are reported along with those from non-porous surfaces such as glass and vinyl siding. Several sorbents were tested for their ability to specifically separate Sr{sup 2+} from these high ionic strength wash waters. Alkali metal and alkaline earth salts were found to be effective counter-ions for decontamination of Sr{sup 2+}, which may facilitate the use of common sorbents, even if their K{sub d} values are <100 mL/g. In practice, low K{sub d} values require the use of large quantities of sorbent. Computer simulations were run using the GoldSim Contaminant Fate Module software package to optimize the efficiency of IWATERS for strontium and account for the technical limitations of the sorbents. This modeling allows greater flexibility to design the wash water recycling system for various end-user specifications including options from rain barrel designs for treating runoff from roofs and facades to larger options like drainage basins for larger-scale wash down activities. (authors)

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DOE OSTI2017

Defining Nature and Extent of Contamination for the Waste Management Area C RCRA Corrective Action Process at the Hanford Site in Southeast Washington - 17403

Determination of the nature and extent of contamination is a critical task in any Resource Conservation and Recovery Act of 1976 (RCRA) Facility Investigation. Nature and extent are typically defined through field investigation results. In some cases, however, physical and/or programmatic limitations on field work can impede efforts to define nature and extent based on field work alone. Both physical and programmatic restrictions affected efforts to characterize soil contamination at Waste Management Area C, on the U.S. Department of Energy's Hanford Site. As a result, fate and transport modeling was undertaken to enhance the definition of the nature and extent of soil contamination at Waste Management Area C. (authors)

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DOE OSTI2016

Low-Altitude Unmanned Aerial Vehicles as a Tool for the Remediation of Radiologically Contaminated Environments - 16257

Following the events at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011, significant quantities of radioactive material were released into the local Japanese as well as the wider global environment. At the fifth anniversary of the incident, much work and expense is still being dedicated to the remediation of a large area of eastern Japan, contaminated primarily with radio-caesium. Due to the complex topography of the geographical area of Japan effected, it is important to understand contaminant evolution/migration at the greatest possible resolution - previous methods have lacked this. An increase in the spatial resolution of radiation mapping over other previous methods has been achieved through the deployment of an unmanned aerial vehicle (UAV). The platform used during this work combined a low-altitude multi-rotor UAV with a lightweight radiation mapping system to achieve sub-meter resolution. Using this system it was possible to measure the distribution of radionuclide contamination at a number of sites within the Fukushima Prefecture region of Japan. Unlike ground-based surveys conducted on foot by humans that attain a comparable resolution, such a system eliminates the potentially significant dose that would otherwise be received, as well as the influence of shielding on results. In addition to providing a rapid and high resolution response to radiological incidents, such monitoring technology has the potential to be a powerful tool in post-operational clean-out (POCO) at nuclear sites undergoing decommissioning worldwide. (authors)

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

Utilization and Application of Kurion Mobile Processing System in Remediation of Radioactively Contaminated Water - 16370

Kurion{sup R} Mobile Processing Systems (KMPS) were deployed in Fukushima as first-of-a- kind at-tank isotope removal systems to remediate Sr from reverse osmosis concentrated salt water. The systems were successful in their efforts and achieved their decontamination and availability goals. The use of KMPS has been considered for other applications where a modular system is of benefit. The use of different Kurion Ion Specific Media (ISM) allows for precision removal of hazardous ions from a variety of waste streams. This paper describes a range of projects in which KMPS modularity will benefit the nuclear industry. The KMPS is a flexible system that can be deployed quickly and efficiently. One treatment system option being considered is the utilization of a KMPS for the removal of contamination from groundwater. Similar to its use in Japan, the KMPS can be sent to remote locations for the direct treatment of ground water. In particular, there are several sites across the world where uranium contamination is a problem. Uranium treatability testing was performed on collected groundwater samples from a radiologically contaminated site. The tests were used to help provide designs for KMPS modifications. These designs included the addition of chemical treatment module for the control of pH and other chemistry, the addition of an ultraviolet module for the destruction of biological material, among others. The tests determined the loading capacities of uranium capture resins (UCR) and media (UCM) for this specific waste stream. Based on uranium loading capacities of 37.3 mg/L (end of test C/C{sub 0} = 0.5) and 54.6 mg/L (extrapolated to C/C{sub 0} = 0.98), and the longevity of the resin (45,911 BV for C/C{sub 0} = 0.5, and 80,556 BV for C/C{sub 0} = 0.98) UCR-1 was selected as the media/resin to be proposed for a uranium treatment system. (authors)

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

NitroJet{sup R}'s Verification Test of Contaminated Water Storage Tank Decontamination in Fukushima Daiichi Nuclear Power Plant - 16489

After the Fukushima Daiichi nuclear disaster, much radioactively contaminated water has generated and has been stored into tanks in the site. Therefore, these contaminated water storage tanks (flange-type) are severely required to be decontaminated in order to be dismantled or to be reused to store cleaner water with less radioactive liquid waste and exposure of workers. Then, IHI Corporation (hereinafter, IHI) have verified that NitroJet{sup R} had capability to decontaminate these tanks under governmental grant (the Validation of technologies for contaminated water management project in the FY2013 Supplementary Budget). For this verification, IHI achieved acquiring DF (decontamination factor) by fabricating radioactive partial mock-ups with Rb-86. Moreover, IHI have demonstrated remote operation of decontamination work by using tank's partially full-scale mock up. (authors)

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DOE OSTI2018

Autonomous Radiation Survey Inside Contaminated Buildings at Fukushima Daiichi with the Riser UAV - 18299

Nuclear decommissioning is constrained and defined by radiation and radioactive contamination. Where radiation is high and its distribution is unknown simply gathering the data needed for project planning can become a challenge. Fukushima Daiichi epitomises this challenge. The complex sequence of events at the plant following the March 2011 earthquake and tsunami has resulted in extensive physical damage and an essentially unpredictable distribution of contamination. TEPCO have applied a range of manual and robotics techniques to map the status of the plant, but many significant areas have remained no-go zones due to a combination of high radiation, physical hazards and obstacles. Further, even in areas where manual survey is feasible, there is strong desire to minimise human exposure to radiation by deploying robots where possible. Riser is a fully autonomous UAV equipped with an infrastructure-free 3D navigation and mapping system, inspection cameras and a CZT spectrometric measurement capability. The system has been custom designed specifically to meet the needs of the nuclear inspection. Riser is capable of accessing areas with dose rates of hundreds of milli-sievert per hour and producing 3D models and radiation surveys with accurately located data points. The data from Riser can subsequently be fused using Createc's N-Visage engine to produce three-dimensional contamination maps which can be used for predictive modelling of future D and D activity. Riser has been deployed at Fukushima Daiichi since March 2017. We present examples of data and analysis outputs, as well as general learning about deploying autonomous robots at a nuclear site. (authors)

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DOE OSTI2018

Design of Ad Hoc Filtration Beds for Treating Contaminated Waste Waters - 18385

We employed the GoldSim Contaminant Transport model to design a system of reactive filtration beds that may be used to selectively remove radioactive cesium and other radionuclides from contaminated waters. These filtration beds can be rapidly constructed ad hoc by using common materials that permit timely, in-field treatment of incoming contaminated waters generated during the response and recovery phase of a radioactive release event. Sensitivity analyses on the system parameters revealed simple relationships between the bed design and the expected breakthrough of cesium, allowing us to generate a concise set of look-up tables to aid the early responders. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Addressing Excess Contaminated Facilities and Mercury Cleanup At the Department of Energy's Oak Ridge Reservation - 18408

The U.S. Department of Energy's Oak Ridge Office of Environmental Management (OREM) and its prime cleanup contractor, URS | CH2M Oak Ridge LLC (UCOR) are executing an aggressive program of cleanup and risk reduction in excess contaminated facilities on the Oak Ridge Reservation (ORR). Across the complex, DOE has designated more than 2,300 of its facilities 'excess'. Excess means 'nonoperational' and refers to a facility for which DOE no longer has a mission need. Many of these facilities pose high risk to workers and/or the environment. Delayed cleanup increases risk as well as cost. OREM and UCOR initiated a Working Group on Excess Facilities to identify and prioritize activities that are needed to enhance worker safety, minimize further degradation of the facilities, and reduce the environmental risk. Six Excess Contaminated Facilities projects on the ORR were identified as priorities. Three of the projects are located at ORNL - the Building 7500 Homogenous Reactor Experiment, the Building 3026 Radioisotope Development Laboratory and Buildings 3028/3029 Isotope Facilities. At Y-12, priority excess facilities include the Column Exchange Equipment (COLEX), the Alpha-4 Lithium Enrichment Facility and the Biology Complex Research Facilities. Work on these projects is aimed at stabilization of degraded higher risk facilities, characterization of conditions and hazards, removal of hazardous materials and placement of the facility in the lowest risk condition possible pending demolition. At the same time, DOE and UCOR are preparing to undertake a comprehensive program to remediate the presence of mercury in the water stemming from historical operations at the Y-12 National Security Complex. Over decades of operations, mercury migrated into the environment. Deteriorating conditions of large post-operation mercury-use buildings may be contributing to additional releases. Mercury cleanup is a high priority for Y-12 and the Oak Ridge Reservation. UCOR is completing the final design on a new Mercury Treatment Facility with construction expected to begin in late 2017. When constructed the treatment facility will reduce the amount of mercury in local waters, lower environmental contamination levels and serve as a guard against future releases. (author)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

3D Time-Lapse Geophysical Imaging Evaluation of Contaminant Migration at the Hanford BY Cribs Site - 18504

Changes in bulk electrical conductivity are governed in large part by two diagnostic parameters concerning the state of vadose zone contamination: saturation and pore fluid conductivity. As a robust, remote, non-invasive, three-dimensional, and scalable imaging tool, time-lapse electrical resistivity tomography (ERT) can provide extensive diagnostic information concerning vadose zone contaminant distribution and migration by imaging changes in bulk electrical conductivity. We demonstrate long-term surface ERT monitoring of a ∼70-m-thick contaminated vadose zone to investigate whether rising groundwater nitrate levels are caused by unanticipated vadose zone flux. A three-dimensional time-lapse image spanning 10 years (2007-2017) reveals the impacts of meteoric surface infiltration events, but ultimately supports the adequacy of current conceptual understanding by indicating that rising nitrate levels are not sourced in the vadose zone. (authors)

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

Panel Session 11: Featured Country Canada - Remediation of Contaminated Sites

Canada has several unique sites requiring environmental remediation of radiological contaminants. This panel was designed to outline the remediation of contaminated sites across Canada from several perspectives. Remote legacy uranium mining operations, small scale residential locations, and large impacted soil sites all pose different challenges, however there are some common solutions and keys to success. This panel addressed several of those challenges and provided lessons learned on how to successfully plan and execute large scale environmental remediation in both remote and residential locations. This panel focused on the cleaning up several contaminated sites in Canada and monitoring the long-term performance of sites that have already been remediated. Panelists addressed the technical and social challenges associated with various cleanup initiatives North of the 49. Parallel and the solutions that have been adopted to enable these projects to move forward. The panel offered the perspectives of owners, contractors and regulators on current projects and how they are leveraging past experience and learning from others to ensure future undertakings are successful. Presentations proposed include: 1 - Regulating Environmental Remediation in Canada (Michael Rinker, Canadian Nuclear Safety Commission (Canada)); 2 - Integration of Local Knowledge and Engagement/Capacity Building Legacy Uranium Mine Sites (Joe Muldoon, Saskatchewan Research Council (Canada)); 3 - The Path to Institutional Control - Safe, Secure and Stable (R. Liam Mooney, Cameco Corporation (Canada)); 4 - Port Hope Area Initiative: Project Challenges (Scott Parnell, Canadian Nuclear Laboratories (Canada))

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

Occurrence of Radiological Contamination in Urban Parks Established over Former Landfill Sites - 19433

In 2005, the National Park Service was notified that elevated radiation levels were detected at Great Kills Park during a baseline radiological mapping effort conducted by the Counter Terrorism Bureau of the New York City Police Department and the United States Department of Energy. Great Kills Park is in the Staten Island Unit of Gateway National Recreation Area. A records search determined that approximately 1.1 x 10{sup 6} square meters (280 acres) of the park was established over an area in which the New York City Department of Sanitation placed approximately 1.2 x 10{sup 7} cubic meters (15.1 million cubic yards) of waste fill from 1944 to 1948. Since 2005, a series of response actions and investigations were conducted on behalf of the National Park Service to mitigate risk to human health and the environment and to determine the nature of radiological contamination at Great Kills Park. The findings support that radiological contamination is related to certain components of waste fill, including incinerator residue from both on and offsite incinerators, coal ash from the historical use of coal-fired boilers for heating, and incidental radiological artifacts in the waste fill due to their historical use and subsequent disposal. A majority of the radiological artifacts were determined to contain Ra-226 and included radioluminescent markers, radium buttons, radium paint containers, and brachytherapy devices. The National Park Service is currently performing a Remedial Investigation for the waste-filled area of Great Kills Park under the Comprehensive Environmental Response, Compensation and Liability Act. Several other Parks in Gateway National Recreation Area were established in areas with a similar history to Great Kills Park, and overlie waste fill historically placed during landfilling operations. Recently, radiological surveys were performed over limited portions of Spring Creek Park in the Jamaica Bay Unit of Gateway National Recreation Area. These surveys identified several locations with gamma radiation levels above the ambient level, several of which were attributable to radiological artifacts similar in nature to those recovered at Great Kills Park. Ongoing investigations at Great Kills Park and the recent findings at Spring Creek Park suggest that radiological contamination may be associated with historical landfilling practices that were common prior to the regulation and control of radioactive materials. (authors)

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