Search NASA⌕ Search

Engineering topics

Kennedy, Chris

Publications and source records attributed to Kennedy, Chris.

Assessment of Rare Earth Element Fingerprints for Distinguishing Between Site-Related Wastes and Background - 19441

Actinides such as uranium, thorium and radium are known to be present in sites associated with various phases of the cold war weapons research, development and production. Remediation of these sites as well as others associated with chemical plants that may have generated radioactive actinide-containing wastes have been the focus of the Formerly Utilized Sites Remedial Action Program (FUSRAP) for the past 20 years. The goal is to remediate a site to established cleanup standards as efficiently and cost-effectively as possible. For radiologically-contaminated sites, one potential challenge is the presence of non-FUSRAP media such as naturally-occurring radioactive material (NORM) or technologically-enhanced naturally-occurring radioactive material (TENORM), from non-FUSRAP sources, at concentrations exceeding site cleanup standards. Such NORM and TENORM, and even byproduct radionuclides from other unrelated activities on or near the site, can be mistaken for project waste and thus incur significant additional excavation and waste transport and disposal costs. Past studies have provided examples of NORM and non-FUSRAP waste and described strategies to distinguish them from FUSRAP waste. This paper describes various sources of NORM, summarizes the types of project-related waste at some active FUSRAP sites, and identifies TENORM sites from which radionuclides could possibly migrate via various environmental pathways to nearby FUSRAP sites. The authors also examine two Case Studies that calculate distinctive elemental ratios and are examples of tools which may be used for distinguishing FUSRAP waste from other radionuclides present in natural or other man-made contributors to background. Case Study I examines two bodies of data and calculates distinctive elemental ratios between pairs of rare earth elements (REE) to see if significant differences may exist between such ratios in unregulated coal ash residue, common in fill in well-established towns and cities, and FUSRAP waste. The first group of data, consisting of eighteen sample results, was obtained from the FUSRAP Maywood Superfund Site's historical data while the second was obtained from a paper which provided extensive data (more than 100 samples) on the REE content in fly ash residues from three major coal-producing areas in the United States. This example illustrates statistically significant differences in five of six REE ratios and thus provides a potential tool for distinguishing FUSRAP waste from coal ash-based NORM. Case Study II examines differences in the mean REE:Actinide and REE:REE ratios in Welsbach-impacted sample results to distinguish project waste from background. While the purpose of this study was to distinguish project waste from background levels of the radionuclides of concern (ROC), it provides a good example of how one or more ratios could potentially be used to distinguish FUSRAP waste from NORM. Lastly, the authors recommend that future projects ensure robust characterization, that considers all potential radionuclide contributors from both FUSRAP activities as well as from other contributors to background for the region during the Planning Phase of the Data Life Cycle described within the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). It is expected that the incremental characterization sampling and analysis costs will be dwarfed by potential savings from efforts to better delineate and limit remediation to FUSRAP wastes rather than other potentially unregulated contributors to regional background. Other agencies or commercial entities with radiological environmental liabilities similar to FUSRAP would benefit from similar considerations of REEs and other radionuclides that could contribute to regional background. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

FUSRAP Case Study - Benefits and Lessons Learned from Implementation of a Modern Data Solution at Maywood - 18399

This paper focuses on data production and management practices dating back to 1999 that continue to evolve to support the project today. In 2000, the FUSRAP Maywood Project began using a software environmental data management system and laboratory information management system, developed by a single database administrator (DA) and authored in Microsoft Access{sup TM} (MS Access). The original databases included basic functionality including sample number assignment and label generation, tracking of LIMS gamma spec QC and assignment of basic qualifiers and basic database queries. The DA continued over the next fifteen years to refine the EDMS/LIMS by integrating project-specific data evaluation guidance document processes and Quality Assurance/Quality Control (QA/QC) charting and excursion warning tools. With the retirement of the original DA, the U.S. Army Corps of Engineers (USACE)-Cabrera Team procured and implemented a commercial-leaning solution using modern database tools and an established EDMS vendor. For the database transition process, the project team established and configured the new EDMS/LIMS with basic architecture and accessibility; evaluated existing workflows; established/revised LIMS and EDMS-related documentation (manuals and procedures); and conducted dry runs and validation testing. The overall team coordinated closely to facilitate a seamless transition from initial assessment and authoring, to data migration, and finally to resumption of normal ongoing operations. Key features of the new EDMS Subcontractor's software included lookup tables, an import wizard, data checking options and unique indexes. Since the database systems became operational, the technical staff gathered useful feedback from end users (e.g., lab staff, field engineers, task managers, and the third-party data validator) to refine the EDMS/LIMS operation. This feedback triggered improvements in the performance of onsite laboratory qualification forms, promoted consistency in sample ID numbers between the database sample planning screens and field chain-of-custodies, corrected bugs in the LIMS Duplicate Evaluation Report, eliminated data import issues such as blank, inconsistent or missing data from key fields. One of the advantages of the commercial database solution was that it allowed the project to cut cost over time due to the lower cost of database maintenance provided by the commercial database vendor versus the cost of an on-staff DA. Cost savings are estimated at $40,000 per year. There were also indirect cost savings resulting from implementation of the new database since it allowed better integration of the LIMS and EDMS. While there will always be challenges associated with long term records/data management for any old remediation site, the Maywood Team's approach to an upgraded EDMS/LIMS implementation serves as one element of the overall effort to enhance the integrity and reproducibility of critical data that supports the remediation program while at the same time, more effectively using available resources. These lessons-learned will enhance implementation of cost-effective solutions for similar environmental remediation sites. (authors)

97 MATHEMATICS AND COMPUTING↗

Maintenance of Maywood Laboratory Operations Support During Contractor Transition and Replacement of the Project Databases - 16329

In December 2013, Cabrera Services (Cabrera) executed transition of the FUSRAP Maywood Superfund Site remediation project operations, including an on-site accredited environmental lab, from a large business that had established technology infrastructure in place for over a decade which required updating to support the expected remediation scope and client needs. As of November 2015, Cabrera has shipped over 116,000 yd{sup 3} of contaminated soil to disposal facilities. During the transition, the USACE FUSRAP Maywood Laboratory (UFML) continued to support project operations, providing the expected timely and reliable results and maintaining their New Jersey Department of Environmental Protection certification for all parameters of concern, while having to cope with new challenges and additional tasks having the potential to disrupt the laboratory's ability to support project operations. This case study examines the challenges with maintaining a certified radiochemistry laboratory and an aggressive remediation schedule during a period of prime contractor transition which included a complete IT infrastructure overhaul, and conversion of the existing Microsoft Access laboratory database and project Electronic Data Management System (EDMS) to a customized commercial solution. Challenges: I. Procurement of a new database subcontractor and working closely with them to achieve the following: a. Migration of all environmental (including radiological, chemical, and quality control), health and safety, and spatial data as well as reports, queries, and analytical instrument software processes from a MS Access data management system to a SQL server system; and b. Verification that the functionality and data integrity of the databases remained intact. II. The onsite laboratory was changed over to a new onsite network and the following tasks were completed with little or no interruption to site operations by January 10, 2014: i. Installation of new instrument personal computers (PCs) and making them fully operational; ii. Configuration of the lab domain and server to host the LIMS (replaced all servers/domain/workstations with Windows 7 and Server 2012 machines). iii. Networking of the laboratory building into the rest of the project site via fiber optic cabling across the site. iv. Upgrade of the wide area network (WAN) data connection to high-speed Fiber Optic service; v. Upgrade of the telephones into voice over internet protocol (VOIP) phones. vi. Splitting of the database into front ends and a centralized back-end hosted on the new server to allow simultaneous access for fixes and improvements. III. Phone service interruption; phone systems were operational by January 10, 2014. Additional Tasks: I. Revision of the USACE FUSRAP Maywood Laboratory (UFML) Quality Systems Manual Rev. 1 Submitted 01/16/14; II. Writing of the Uniform Federal Policy Quality Assurance Project Plan Rev. 1 (UFP-QAPP) submitted 1/21/14. This document replaced the prior project data quality plan, the Chemical Data Quality Management Plan. III. Support of USACE communications to the New Jersey Department of Environmental Protection (NJDEP) on lab management and personnel transition to Cabrera. This work was important since it ensured a smooth transition and shows how critical project records infrastructure such as databases, can be upgraded with minimal interruption of project support. Such work may provide benefit to other similar projects, especially long term projects where database infrastructure upgrades may be beneficial in terms of improved efficiencies in data recording and transfer, and improved security in data storage. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Generalized Perturbation Theory-Free Sensitivity Analysis for Eigenvalue Problems

Generalized perturbation theory (GPT) has been recognized as the most computationally efficient approach for performing sensitivity analysis for models with many input parameters, which renders forward sensitivity analysis computationally overwhelming. In critical systems, GPT involves the solution of the adjoint form of the eigenvalue problem with a response-dependent fixed source. Although conceptually simple to implement, most neutronics codes that can solve the adjoint eigenvalue problem do not have a GPT capability unless envisioned during code development. We introduce in this manuscript a reduced-order modeling approach based on subspace methods that requires the solution of the fundamental adjoint equations but allows the generation of response sensitivities without the need to set up GPT equations, and that provides an estimate of the error resulting from the reduction. Moreover, the new approach solves the eigenvalue problem independently of the number or type of responses. This allows for an efficient computation of sensitivities when many responses are required. This paper introduces the theory and implementation details of the GPT-free approach and describes how the errors could be estimated as part of the analysis. The applicability is demonstrated by estimating the variations in the flux distribution everywhere in the phase space of a fast critical sphere and a high-temperature gas-cooled reactor prismatic lattice. The variations generated by the GPT-free approach are benchmarked to the exact variations generated by direct forward perturbations.

99 GENERAL AND MISCELLANEOUS↗