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Featured researches published by Sandra F. Snyder.


Journal of Environmental Radioactivity | 2015

Development of criteria used to establish a background environmental monitoring station.

Bradley G. Fritz; J. Matthew Barnett; Sandra F. Snyder; Lynn E. Bisping; Jeremy P. Rishel

It is generally considered necessary to measure concentrations of contaminants-of-concern at a background location when conducting atmospheric environmental surveillance. This is because it is recognized that measurements of background concentrations can enhance interpretation of environmental monitoring data. Despite the recognized need for background measurements, there is little published guidance available that describes how to identify an appropriate atmospheric background monitoring location. This paper develops generic criteria that can guide the decision making process for identifying suitable locations for background atmospheric monitoring station. Detailed methods for evaluating some of these criteria are also provided and a case study for establishment of an atmospheric background surveillance station as part of an environmental surveillance program is described. While the case study focuses on monitoring for radionuclides, the approach is equally valid for any airborne constituent being monitored. The case study shows that implementation of the developed criteria can result in a good, defensible choice for a background atmospheric monitoring location.


Archive | 2010

Data Quality Objectives Supporting Radiological Air Emissions Monitoring for the PNNL Site

J. Matthew Barnett; Kirsten M. Meier; Sandra F. Snyder; Brad G. Fritz; Ted M. Poston; Kathleen Rhoads

This document of Data Quality Objectives (DQOs) was prepared based on the U.S. Environmental Protection Agency (EPA) Guidance on Systematic Planning Using the Data Quality Objectives Process, EPA, QA/G4, 2/2006 (EPA 2006) as well as several other published DQOs. Pacific Northwest National Laboratory (PNNL) is in the process of developing a radiological air monitoring program for the PNNL Site that is distinct from that of the nearby Hanford Site. Radiological emissions at the PNNL Site result from Physical Sciences Facility (PSF) major emissions units. A team was established to determine how the PNNL Site would meet federal regulations and address guidelines developed to monitor and estimate offsite air emissions of radioactive materials. The result is a program that monitors the impact to the public from the PNNL Site.


Archive | 2013

Pacific Northwest National Laboratory Site Radionuclide Air Emissions Report for Calendar Year 2011

Sandra F. Snyder; J. Matthew Barnett; Lynn E. Bisping

This report documents radionuclide air emissions that result in the highest effective dose equivalent (EDE) to a member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations (CFR), Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants (NESHAP), Subpart H, National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities and Washington Administrative Code (WAC) Chapter 246-247, Radiation Protection Air Emissions. The dose to the PNNL Site MEI due to routine major and minor point source emissions in 2013 from PNNL Site sources is 2E-05 mrem (2E-07 mSv) EDE. The dose from fugitive emissions (i.e., unmonitored sources) is 2E-6 mrem (2E-8 mSv) EDE. The dose from radon emissions is 1E-11 mrem (1E-13 mSv) EDE. No nonroutine emissions occurred in 2013. The total radiological dose for 2013 to the MEI from all PNNL Site radionuclide emissions, including fugitive emissions and radon, is 2E-5 mrem (2E-7 mSv) EDE, or 100,000 times smaller than the federal and state standard of 10 mrem/yr, to which the PNNL Site is in compliance


Archive | 2012

Data Quality Objectives Supporting Radiological Air Emissions Monitoring for the Marine Sciences Laboratory, Sequim Site

J. Matthew Barnett; Kirsten M. Meier; Sandra F. Snyder; Ernest J. Antonio; Brad G. Fritz; Theodore M. Poston

This document of Data Quality Objectives (DQOs) was prepared based on the U.S. Environmental Protection Agency (EPA) Guidance on Systematic Planning Using the Data Quality Objectives Process, EPA, QA/G4, 2/2006 (EPA 2006), as well as several other published DQOs. The intent of this report is to determine the necessary steps required to ensure that radioactive emissions to the air from the Marine Sciences Laboratory (MSL) headquartered at the Pacific Northwest National Laboratory’s Sequim Marine Research Operations (Sequim Site) on Washington State’s Olympic Peninsula are managed in accordance with regulatory requirements and best practices. The Sequim Site was transitioned in October 2012 from private operation under Battelle Memorial Institute to an exclusive use contract with the U.S. Department of Energy, Office of Science, Pacific Northwest Site Office.


Archive | 2014

Establishment of a Background Environmental Monitoring Station for the PNNL Campus

Brad G. Fritz; Sandra F. Snyder; J. Matthew Barnett; Lynn E. Bisping; Jeremy P. Rishel

The environmental surveillance of background levels of radionuclides and, in particular, the siting of a background environmental surveillance (monitoring) station are examined. Many published works identify and stress the need for background monitoring; however, little definitive and comprehensive information for siting a station exists. A definition of an ideal background monitoring location and the generic criteria recommended for use in establishing such a background monitoring location are proposed. There are seven primary (mandatory) criteria described with two additional, optional criteria. The criteria are applied to the Richland, Washington (WA), Pacific Northwest National Laboratory (PNNL) Campus, which currently uses background monitoring data from the nearby Hanford Site. Eleven potential background monitoring sites were identified, with one location in Benton City, WA found to meet all of the mandatory and optional criteria. It is expected that the new sampler will be installed and operating by the end of June, 2015.


ASME 2009 International Mechanical Engineering Congress and Exposition | 2009

Scaled Experiments Evaluating Pulse Jet Mixing of Slurries

Judith Ann Bamberger; Perry A. Meyer; Carl W. Enderlin; James A. Fort; Beric E. Wells; Michael J. Minette; Carolyn A. Burns; Ellen Bk Baer; David E. Eakin; Monte R. Elmore; Sandra F. Snyder

Pulse jet mixing (PJM) tests with noncohesive solids in Newtonian liquid were conducted at three geometric scales to support the design of mixing systems for the Hanford Waste Treatment and Immobilization Plant. The test data will be used to develop mixing models. The models predict the cloud height (the height to which solids will be lifted by the PJM action) and the critical suspension velocity (the minimum velocity needed to ensure all solids have been lifted from the floor), two parameters measured during the tests. From the cloud height estimate, the concentration of solids near the vessel floor and the minimum velocity predicted to lift solids can be calculated. The test objective was to observe the influence of vertically downward-directed jets on noncohesive solids in a series of scaled tanks with several bottom shapes. The test tanks and bottom shapes included small- and large-scale tanks with elliptical bottoms, a mid-scale tank with a spherical bottom, and a large-scale tank with a flanged and dished bottom. During testing, the downward-directed jets were operated in either a steady flow condition or a pulsed (periodic) flow condition. The mobilization of the solids resulting from the jets was evaluated based on: the motion/agitation of the particulate on the tank floor and the elevation the solids reach within the tank; the height the solids material reaches in the tank is referred to as the cloud height (HC ).Copyright


Health Physics | 2017

Location Modification Factors for Potential Dose Estimation

Sandra F. Snyder; J. Matthew Barnett

Abstract A U.S. Department of Energy facility must comply with the National Emission Standard for Hazardous Air Pollutants for radioactive air emissions. The standard is an effective dose of less than 0.1 mSv y−1 to the maximum public receptor. Additionally, a lower dose level may be assigned to a specific emission point in a State issued permit. A method to efficiently estimate the expected dose for future emissions is described. This method is most appropriately applied to a research facility with several emission points with generally low emission levels of numerous isotopes.


Archive | 2013

Sequim Site Radionuclide Air Emissions Report for Calendar Year 2012

Sandra F. Snyder; J. Matthew Barnett; Todd L. Gervais

This report is prepared to document compliance with the Code of Federal Regulations (CFR), Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants (NESHAP), Subpart H, National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities and ashington Administrative Code (WAC) Chapter 246-247, Radiation Protection Air Emissions. This report meets the calendar year 2012 Sequim Site annual reporting requirement for its operations as a privately-owned facility as well as its federally-contracted status that began in October 2012. Compliance is indicated by comparing the estimated dose to the maximally exposed individual (MEI) with the 10 mrem/yr Environmental Protection Agency (EPA) standard. The MSL contains only sources classified as fugitive emissions. Despite the fact that the regulations are intended for application to point source emissions, fugitive emissions are included with regard to complying with the EPA standard. The dose to the Sequim Site MEI due to routine operations in 2012 was 9E-06 mrem (9E-08 mSv). No non-routine emissions occurred in 2012. The MSL is in compliance with the federal and state 10 mrem/yr standard.


Archive | 2011

Department of Energy – Office of Science Pacific Northwest Site Office Environmental Monitoring Plan for the DOE-SC PNNL Site

Sandra F. Snyder; Kirsten M. Meier; J. Matthew Barnett; Lynn E. Bisping; Ted M. Poston; Kathleen Rhoads

The Pacific Northwest Site Office (PNSO) manages the contract for operations at the U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest National Laboratory (PNNL) Site in Richland, Washington. Radiological operations at the DOE-SC PNNL Site expanded in 2010 with the completion of facilities at the Physical Sciences Facility. As a result of the expanded radiological work at the site, the Washington State Department of Health (WDOH) has required that offsite environmental surveillance be conducted as part of the PNNL Site Radioactive Air Emissions License. The environmental monitoring and surveillance requirements of various orders, regulations, and guidance documents consider emission levels and subsequent risk of negative human and environmental impacts. This Environmental Monitoring Plan (EMP) describes air surveillance activities at the DOE-SC PNNL Site. The determination of offsite environmental surveillance needs evolved out of a Data Quality Objectives process (Barnett et al. 2010) and Implementation Plan (Snyder et al. 2010). The entire EMP is a compilation of several documents, which include the Main Document (this text), Attachment 1: Sampling and Analysis Plan, Attachment 2: Data Management Plan, and Attachment 3: Dose Assessment Guidance.


Archive | 2009

Pulse Jet Mixing Tests With Noncohesive Solids

Perry A. Meyer; Judith Ann Bamberger; Carl W. Enderlin; James A. Fort; Beric E. Wells; S. K. Sundaram; Paul A. Scott; Michael J. Minette; Gary L. Smith; Carolyn A. Burns; Margaret S. Greenwood; Gerald P. Morgen; Ellen Bk Baer; Sandra F. Snyder; M. White; Gregory F. Piepel; Brett G. Amidan; Alejandro Heredia-Langner; Sharon A. Bailey; John C. Bower; Kayte M. Denslow; David E. Eakin; Monte R. Elmore; Phillip A. Gauglitz; Anthony D. Guzman; Brian K. Hatchell; Derek F. Hopkins; David E. Hurley; Michael D. Johnson; Leslie J. Kirihara

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J. Matthew Barnett

Pacific Northwest National Laboratory

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Lynn E. Bisping

Pacific Northwest National Laboratory

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Brad G. Fritz

Pacific Northwest National Laboratory

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Beric E. Wells

Pacific Northwest National Laboratory

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Carl W. Enderlin

Battelle Memorial Institute

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Carolyn A. Burns

Pacific Northwest National Laboratory

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David E. Eakin

Pacific Northwest National Laboratory

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Ellen Bk Baer

Pacific Northwest National Laboratory

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James A. Fort

Battelle Memorial Institute

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Jeremy P. Rishel

Pacific Northwest National Laboratory

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