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Johnson, Jeremy

Publications and source records attributed to Johnson, Jeremy.

13 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

FRMAC Assessment Manual Volume 1 (Overview and Methods)

The Federal Radiological Monitoring and Assessment Center (FRMAC) Assessment Manual is the tool used to organize and guide activities of the FRMAC Assessment Division. The mission of the FRMAC Assessment Division in a radiological emergency is to interpret radiological data and predict worker and public doses. This information is used by Decision Makers to recommend protective actions in accordance with Protection Action Guides (PAGs) issued by government agencies. This manual integrates many health physics tools and techniques used to make these assessments.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Solver for hardware based computing

Full-AC load flow constitutes a core computation in power system analysis. A performance gain with a hardware implementation of a sparse-linear solver using a Field Programmable Gate Array (FPGA) is achieved by use of a DC network emulation of the power system bus. Analog Behavioral Models (ABMs) are used in an efficient strategy for designing analog emulation engines for large-scale power system computation. A generator model is also developed using analog circuits for load flow emulation for power system analysis to reduce computation time. The generator model includes reconfigurable parameters using operational transconductance amplifiers (OTAs). The circuit module is used with other reconfigurable circuits, i.e., transmission lines and loads.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

FRMAC Assessment Manual Volume 1: Overview and Methods

This Federal Radiological Monitoring and Assessment Center (FRMAC) Assessment Manual has been prepared by representatives of those Federal and State agencies that can be expected to play the major roles during a radiological emergency. Federal Agencies include: the National Nuclear Security Administration (NNSA), the Nuclear Regulatory Commission (NRC), the Environmental Protection Agency (EPA), the Department of Agriculture (USDA), the Food and Drug Administration (FDA), and the Centers for Disease Control (CDC). This final manual was reviewed by experts from across the community and their input has been incorporated.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2016

Hanford Single-Shell Tank and Double-Shell Tank Integrity Programs - 16390

Waste at Hanford is stored in 149 single-shell tanks and 28 double-shell tanks. Concerns related to aging radioactive waste storage facilities throughout the DOE complex led to Brookhaven National Laboratory (BNL) developing guidelines for structural integrity programs for tank systems. The committee of experts who developed these guidelines is commonly known as the Tank Structural Integrity Panel (TSIP). The DOE has subsequently adopted these guidelines, and requires site operators to have a program consistent with them. The Double-Shell Tank (DST) integrity is maintained with a variety of activities such as ultrasonic and visual inspections, chemistry controls, corrosion monitoring and structural analyses methods. In October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of 241-AY-102 was leaking. WRPS contracted a panel of experts from industry and academia to provide advice and recommendations for the DST Integrity Program. The panel focused on three concerns: - No Early warning - Determine why the existing DST Integrity Program did not predict a primary tank failure or provide early warning of the pending failure. - Program improvements - Recommend activities to either predict a primary tank failure or increase the probability of early warning. - Forensic recommendations - The panel provided additional recommendations regarding forensic assessment of Tank 241-AY-102 (AY-102) to facilitate a conclusion on why the leak occurred. WRPS has prepared a response to the concerns of the panel coupled with recommendations for project action to strengthen the DST Integrity Program [4]. The purpose of this DST Integrity Improvement Plan is to translate the recommendations to specific project activities that are technically and practically responsive. To improve the understanding of the Single-Shell Tank (SST) integrity, WRPS, the Department of Energy-Office of River Protection tank operations contractor, developed an enhanced Single-Shell Tank Integrity Project (SSTIP) in 2009. An expert panel on SST integrity, consisting of various subject matter experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration. In late 2010, seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for the Hanford Federal Agreement and Compliance Order, also known as the Tri-Party Agreement. The change package identified two phases of work for SST integrity. The initial phase, which was completed in 2015, was focused on efforts to envelope the integrity of the tanks. It was divided into two primary areas of investigation: structural integrity and leak integrity. If necessary, based on the outcome from the initial work, a second phase would be focused on further definition of the integrity of the tanks and liners. The two combined phases are designed to support the formal integrity assessment of the Hanford SSTs in 2018 by an Independent Qualified Registered Professional Engineer. This paper will summarize the current status of the DST and SST Integrity Programs and discuss the ongoing efforts to improve these programs. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Minimizing environmental risk through the use of evaporation - 15090

At the Hanford Site, work is being done to utilize a portable exhauster to reduce the remaining free liquid in the older underground storage tanks. Use of an exhauster allows the water in the free liquid to be evaporated reducing the possibility that mobile contaminants will leak into the soil and groundwater. Transferring the remaining liquid waste to newer tanks requires major infrastructure installation. Currently one set of tanks is undergoing the retrieval of solids and liquids. This retrieval requires substantial infrastructure in order to mobilize and pump the waste to newer tanks. Reducing the remaining liquid waste by pumping would require much of the same retrieval infrastructure and is cost prohibitive. The use of a portable exhauster will require minimal infrastructure and is much more efficient. Past results have demonstrated that this technology can be successfully used on various sizes of underground storage tanks. A portable exhauster is planned to be connected to the one tank believed to be leaking and will be used to evaporate the remaining free liquid, beginning in 2015. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Hanford double-shell tank testing program - 15341

The corrosion testing program and Hanford regularly tests waste chemistries to analyze threats and develop new corrosion chemistry guidelines. Over the past few years, the focus of testing has been on the threat of leaked wastes in Tank 241-AY-102 (AY-102). From the tests conducted to date, it appears that the potential waste compositions in the annulus of tank AY-102 do not show a propensity for localized corrosion or stress corrosion cracking. The threat of exterior corrosion from the liquid and moisture in the leak detection pit (LDP) is a potential concern that will continue to be evaluated in the coming year. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Hanford single-shell tanks 241-t-203 and 241-t-204 validation of level decrease evaluation - 15343

Hanford single-shell tanks (SSTs) 241-T-203 (T-203) and 242-T-204 (T-204) were two tanks that showed decreasing waste surface level trends. All factors that could impact each tank's level change rate were evaluated with the conclusion being the level decreases could be explained by evaporation. The evaporation estimates contained several assumptions, so a test was performed to determine if the estimates could be supported by data. The breather filter valves on these two tanks were closed for one year in order to shut off the primary means of tank air exchange to the atmosphere. The results for tank T-203 showed the net level change for the year was zero which supported the evaporation rate estimate (and provided further information that the tank was not leaking). The data for tank T-204 were very erratic and prevented conclusive results, but the waste level showed a significant reduction in level decrease rate and supported the tank evaporation rate estimate. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Progress of the enhanced Hanford single shell tank (SST) integrity project - 15497

To improve understanding of the single-shell tanks (SSTs) integrity, Washington River Protection Solutions, LLC (WRPS), the US DOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank Integrity Project (SSTIP) in 2009. An expert panel on SST integrity, consisting of various subject matter experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration. In late 2010, seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for the Hanford Federal Agreement and Compliance Order, which is also known as the Tri-Party Agreement. The change package identified two phases of work for SST integrity. The initial phase was focused on efforts to envelope the integrity of the tanks. The initial phase was divided into two primary areas of investigation: structural integrity and leak integrity. If necessary, based on the outcome from the initial work, second phase would be focused on further definition of the integrity of the tanks and liners. Combined these two phases are designed to support the formal integrity assessment of the Hanford SSTs in 2018 by an Independent Qualified Registered Engineer. As the initial phase of this work completes in early 2015, this paper summarizes the project formation and status the work of the past few years associated the implementation of the Phase one recommendations. Work in the initial phase to further define the DOE's understanding of the structural integrity SSTs involved preparing a modern Analysis of Record (AOR) using finite element analysis. Structural analyses of the SSTs have been conducted since 1957, but these analyses used analog calculations, less rigorous models, or focused on individual structures. As such, an integrated understanding of all of the SSTs has not been developed to modern expectations. In support of this effort, other activities addressed the visual inspection of tank internal conditions and the collection of concrete core samples from the tanks, including a full height tank sidewall core, for analysis of current mechanics properties. The work on the liner leak integrity has examined leaks from 25 tanks with known liner failures. Individual leak assessments were developed for each tank to identify the leak cause and location and estimate historic leak rates. A common cause/failure analysis study was performed to take data from individual tanks to look for trends in the causes of failure. A separate activity is being conducted to examine the propensity for corrosion in select SSTs with aggressive waste layers. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Hanford double-shell tank extent-of-condition construction review - 15498

During routine visual inspections of Hanford double-shell waste tank 241-AY-102 (AY-102), anomalies were identified on the annulus floor which resulted in further evaluations. Following a formal leak assessment in October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of AY-102 was leaking. A formal leak assessment, documented in RPP-ASMT-53793, Tank 241-AY-102 Leak Assessment Report, identified first-of-a-kind construction difficulties and trial-and-error repairs as major contributing factors to tank failure. To determine if improvements in double-shell tank (DST) construction occurred after construction of tank AY-102, a detailed review and evaluation of historical construction records was performed for Hanford's remaining twenty-seven DSTs. Review involved research of 241 boxes of historical project documentation to better understand the condition of the Hanford DST farms, noting similarities in construction difficulties/issues to tank AY-102. Information gathered provides valuable insight regarding construction difficulties, future tank operations decisions, and guidance of the current tank inspection program. Should new waste storage tanks be constructed in the future, these reviews also provide valuable lessons-learned.(authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Hanford single-shell tank sidewall coring Project - 15548

As part of an enhanced Single-Shell Tank (SST) integrity project, Washington River Protection Solutions, the US DOE Hanford site Tank Operations Contractor, established an expert panel to provide recommendations for implementation of the project. In one of the main areas of interest, structural integrity, the panel recommended obtaining and testing a vertical core from the entire depth of the sidewall for SSTs that have leaked and have been operated at high temperatures for extended periods. Due to concerns over handling contaminated samples, the panel later recommended that the evaluation focus only on thermal degradation. SST 241-A-106 was selected as the best choice for sidewall coring based on heat exposure and other factors. During site preparation activities, nondestructive testing and evaluation of the exposed tank dome and sidewall was performed using impact echo, spectral analysis of surface waves, and sonic echo/impulse response acoustic wave test methods. Good results were observed in the tests performed on the dome, but results were inconclusive for the full wall height due to signal damping. Results indicated that no cracking was predicted in the upper wall. Sidewall coring of tank A-106 was completed over two weeks in May 2014. Over 38 feet of concrete core was successfully removed, to a depth approximately halfway through the tank footing. Nondestructive and destructive physical testing of the concrete core specimens was successfully performed and included visual examination and determination of transverse and longitudinal resonant frequency and dynamic modulus of elasticity; pulse velocity; static modulus of elasticity; Poisson's ratio; and compressive strength. The testing indicated favorable results with values generally greater, and in many cases significantly greater, than expected in comparison with the values originally specified and those used in the current structural analysis of record. Petrographic analysis was performed to assess the quality and condition of the concrete and the extent of any deterioration or deleterious reactions occurring within the concrete, and determined that the concrete within the examined core segments is in overall good condition, with a minor amount of microcracking and minor evidence of deleterious mechanisms that do not appear to have significantly affected the overall quality and integrity of the concrete. The results of the testing performed on the concrete core removed from the sidewall of SST 241-A-106 do not reveal any deficiencies with the structural integrity of the tank. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2013

Advanced Caution and Warning System, Final Report - 2011

The work described in this report is a continuation of the ACAWS work funded in fiscal year (FY) 2010 under the Exploration Technology Development Program (ETDP), Integrated Systems Health Management (ISHM) project. In FY 2010, we developed requirements for an ACAWS system and vetted the requirements with potential users via a concept demonstration system. In FY 2011, we developed a working prototype of aspects of that concept, with placeholders for technologies to be fully developed in future phases of the project. The objective is to develop general capability to assist operators with system health monitoring and failure diagnosis. Moreover, ACAWS was integrated with the Discrete Controls (DC) task of the Autonomous Systems and Avionics (ASA) project. The primary objective of DC is to demonstrate an electronic and interactive procedure display environment and multiple levels of automation (automatic execution by computer, execution by computer if the operator consents, and manual execution by the operator).

Spirkovska, Lilly↗