Stephen P. LaMont

Bio: Stephen P. LaMont is an academic researcher from Los Alamos National Laboratory. The author has contributed to research in topics: Uranium & Chemistry. The author has an hindex of 7, co-authored 34 publications receiving 203 citations. Previous affiliations of Stephen P. LaMont include University of Cincinnati & United States Department of Energy.

The urgent requirement for new radioanalytical certified reference materials for nuclear safeguards, forensics, and consequence management

Abstract: A multi-agency workshop was held from 25 to 27 August 2009, at the National Institute of Standards and Technology (NIST), to identify and prioritize the development of radioanalytical Certified Reference Materials (CRMs, generally provided by National Metrology Institutes; Standard Reference Materials, a CRM issued by NIST) for field and laboratory nuclear measurement methods to be used to assess the consequences of a domestic or international nuclear event. Without these CRMs, policy makers concerned with detecting proliferation and trafficking of nuclear materials, attribution and retribution following a nuclear event, and public health consequences of a nuclear event would have difficulty making decisions based on analytical data that would stand up to scientific, public, and judicial scrutiny. The workshop concentrated on three areas: post-incident Improvised Nuclear Device (IND) nuclear forensics, safeguard materials characterization, and consequence management for an IND or a Radiological Dispersion Device detonation scenario. The workshop identified specific CRM requirements to fulfill the needs for these three measurement communities. Of highest priority are: (1) isotope dilution mass spectrometry standards, specifically 233U, 236gNp, 244Pu, and 243Am, used for quantitative analysis of the respective elements that are in critically short supply and in urgent need of replenishment and certification; (2) CRMs that are urgently needed for post-detonation debris analysis of actinides and fission fragments, and (3) CRMs used for destructive and nondestructive analyses for safeguards measurements, and radioisotopes of interest in environmental matrices.

Nuclear, chemical, and physical characterization of nuclear materials

Abstract: The goal of nuclear forensics is to establish an unambiguous link between illicitly trafficked nuclear material and its origin The Los Alamos National Laboratory (LANL) Nuclear Materials Signatures Program has implemented a graded “conduct of operations” type analysis flow path approach for determining the key nuclear, chemical, and physical signatures needed to identify the manufacturing process, intended use, and origin of interdicted nuclear material This analysis flow path includes both destructive and non-destructive characterization techniques and has been exercized against different nuclear materials from LANL’s special nuclear materials archive Results obtained from the case study will be presented to highlight analytical techniques that offer the critical attribution information

Nuclear forensics—metrological basis for legal defensibility

Abstract: The admissibility of nuclear forensics measurements and opinions derived from them in US Federal and State courts are based on criteria established by the US Supreme Court in the case of Daubert v. Merrell Dow and the 2000 Amendment of Rule 702 of the Federal Rules of Evidence. These criteria are being addressed by new efforts that include the development of certified reference materials (CRMs) to provide the basis for analytical method development, optimization, calibration, validation, quality control, testing, readiness, and declaration of measurement uncertainties. Quality data is crucial for all stages of the program, from R&D, and database development, to actual casework. Weakness at any point in the program can propagate to reduce the confidence of final conclusions. The new certified reference materials will provide the necessary means to demonstrate a high level of metrological rigor for nuclear forensics evidence and will form a foundation for legally defensible nuclear chemical analysis. The CRMs will allow scientists to devise validated analytical methods, which can be corroborated by independent analytical laboratories. CRMs are required for ISO accreditation of many different analytical techniques which may be employed in the analysis of interdicted nuclear materials.

Plutonium determination in bioassay samples using radiochemical thermal ionization mass spectrometry

Abstract: A new high-sensitivity plutonium bioassay program employing thermal ionization mass spectrometry (TIMS) has been developed to monitor Savannah River Site employees for intakes of PuO2. The U.S. Department of Energy requires bioassay laboratories which have the ability to detect a 100 mRem, 50-year committed effective dose equivalent (CEDE) intake of radioactive material. For PuO2, traditional alpha-spectrometry methods are not sensitive enough to meet this specification. To comply with this requirement, a radiochemical TIMS method was developed to determine Pu in urine bioassay samples. Four radiochemical separation steps were used to purify Pu from urine to ensure samples were free from matrix effects that interfere with TIMS analysis. These included precipitation, ion-extraction chromatography, electrodeposition, and ion-exchange chromatography. A batch of reagent blanks determined the detection limit for this method was 0.59 fg 239Pu/l (1.3 µBq 239Pu/l). The 239Pu concentration was also measured in 20 urine blank samples to determine the minimum 239Pu concentration that would indicate an occupational intake. A Probit plot was constructed for the results and the 99 th percentile of the urine blanks showed that the minimum 239Pu concentration that would indicate an uptake was 2.4 fg/l (5.5 µBq/l).

The Environmental Protection Agency

Abstract: The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

Nondestructive sampling of living systems using in vivo solid-phase microextraction.

Abstract: Nondestructive Sampling of Living Systems Using in Vivo Solid-Phase Microextraction Gangfeng Ouyang,* Dajana Vuckovic, and Janusz Pawliszyn* MOEKeyLaboratory of Aquatic Product Safety/KLGHEI of Environment andEnergyChemistry, School ofChemistry andChemical Engineering, Sun Yat-sen University, Guangzhou 510275, China Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada