EPA 402-R-06-007 www.epa.gov October 2006 Inventory of Radiological Methodologies For Sites Contaminated With Radioactive Materials U.S. Environmental Protection Agency Office of Air and Radiation Office of Radiation and Indoor Air National Air and Radiation Environmental Laboratory Montgomery, AL 36115 Inventory of Radiological Methodologies This report was prepared for the National Air and Radiation Environmental Laboratory of the Office of Radiation and Indoor Air, United States Environmental Protection Agency. It was prepared by Environmental Management Support, Inc., of Silver Spring, Maryland, under contract 68-W-00-084, work assignment 46, and contract 68-W-03-038, work assignments 10 and 26, all managed by David Garman. Mention of trade names or specific applications does not imply endorsement or acceptance by EPA. For further information, contact Dr. John Griggs, U.S. EPA, Office of Radiation and Indoor Air, National Air and Radiation Environmental Laboratory, 540 South Morris Avenue, Montgomery, AL 36115-2601. Inventory of Radiological Methodologies Preface This compendium is part of a continuing effort by the Office of Radiation and Indoor Air and the Office of Superfund Remediation and Technology Innovation to provide guidance to engineers and scientists responsible for managing the cleanup of sites contaminated with radioactive materials. The document focuses on the radionuclides likely to be found in soil and water at cleanup sites contaminated with radioactive materials. However, its general principles apply also to other media that require analysis to support cleanup activities. It is not a complete catalog of analytical method­ ologies, but rather is intended to assist project managers in understanding the concepts, require­ ments, practices, and limitations of radioanalytical laboratory analyses of environmental samples. As with any technical endeavor, actual radioanalytical projects may require particular methods or techniques to meet specific analytical protocol specifications and data quality objectives. Detailed guidance on recommended radioanalytical practices may be found in current editions of the Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP) and the Multi- Agency Radiation Survey and Site Investigation Manual (MARSSIM), both referenced in this document. Comments on this document, or suggestions for future editions, should be addressed to: Dr. John Griggs U.S. Environmental Protection Agency Office of Radiation and Indoor Air National Air and Radiation Environmental Laboratory 540 South Morris Avenue Montgomery, AL 36115-2601 (334) 270-3450 [email protected] Inventory of Radiological Methodologies Acknowledgments This manual was developed by the National Air and Radiation Environmental Laboratory (NAREL) of EPA’s Office of Radiation and Indoor Air (ORIA) in collaboration with ORIA’s Radiation Protection Division’s Site Cleanup Center and with support from the Office of Superfund Remediation and Technology Innovation. Dr. John Griggs served as project lead for this document. Several individuals provided valuable support and input to this document throughout its development. Special acknowledgment and appreciation are extended to Mr. Stuart Walker, Office of Superfund Remediation and Technology Innovation; Mr. Ronald Wilhelm, Office of Radiation and Indoor Air; Ms. Schatzi Fitz-James, Office of Emergency Management, Homeland Security Laboratory Response Center; and Mr. David Garman, Office of Radiation and Indoor Air, NAREL. Numerous individuals both inside and outside of EPA provided peer review of this document, and their suggestions contributed greatly to the quality and consistency of the final document. Technical support was provided by Dr. N. Jay Bassin, Dr. Robert Litman, Dr. David McCurdy, and Mr. Robert Shannon of Environmental Management Support, Inc. Inventory of Radiological Methodologies Contents List of Figures .............................................................. vii List of Tables ............................................................... vii Acronyms and Abbreviations ................................................... ix Radiometric Unit Conversions .................................................. xii 1 Introduction ...............................................................1 1.1Scope and Purpose .......................................................2 1.2Principles of Radioactivity.................................................3 1.3 Radioactive Decay Chains .................................................5 1.4 Radionuclides Covered in this Document .....................................5 2 Overview of a Cleanup Process and Radiological Methodologies .....................7 2.1 Laboratory and Field Screening Methodologies ................................7 2.1.1 Gross Alpha and Gross Beta Methods ..................................7 2.1.2 Gamma Analysis ..................................................9 2.2 Routine Methodologies ..................................................10 2.2.1 Gross Alpha and Gross Beta Methods .................................10 2.2.2 Spectrometric Methods ............................................10 2.3 Specialized Methodologies ...............................................11 2.3.1 Mass Spectrometric Methods ........................................11 2.3.2 Kinetic Phosphorimetry Analysis ....................................11 2.4 Measurement Quality Objectives and Methodologies ...........................12 3 General Analytical Considerations ............................................12 3.1Site Source Term .......................................................13 3.1.1 DOE Site Cleanup ................................................13 3.1.2 Naturally Occurring Radioactive Materials Waste .......................14 3.2Sample Preservation and Transport .........................................16 3.2.1 Water ..........................................................17 3.2.2 Soil ............................................................19 3.3 Parameters Affecting Quantification Using Radioactive Decay Counting Techniques . 19 3.4Negative Results .......................................................20 3.5Measurement Uncertainty ................................................21 3.6 Sample Analysis Turnaround Time .........................................22 3.6.1 Sample Receipt by the Laboratory ....................................23 3.6.2 Sample Preparation Before Analysis ..................................23 3.6.3 Homogeneity and Adequate Sample Preparation ........................24 3.6.4 Sample Digestion .................................................25 3.6.5 Oxidation State and Speciation of Radionuclides in Environmental Samples . 25 3.6.6 Addition of Radiotracers or Carriers ..................................27 3.7Chemical Separation Process..............................................27 3.8Sample Counting .......................................................28 3.9Data Review and Report Generation ........................................28 v Inventory of Radiological Methodologies 3.10 Units Used in Radioactivity Measurements ................................29 3.11 Measurement Quality Objectives and Performance Testing ...................29 3.12 Selecting a Method ..................................................30 3.12.1 Performance-Based Method Selection .................................30 3.12.2 Sources for Specific Method Information Available to the General Public ....31 4 Radioanalytical Methodologies ...............................................31 4.1 Radioactive Decay Emissions Measurements .................................32 4.1.1 Gas Proportional Counting .........................................32 4.1.2 Liquid Scintillation ...............................................32 4.1.2.1 Routine LSC Analysis ..........................................33 4.1.2.2 Photon-Electron Rejecting Alpha Liquid Scintillation .................33 4.1.2.3 Cerenkov Counting ............................................34 4.1.3 Gamma Spectrometry .............................................34 4.1.4 Alpha Spectrometry ...............................................36 4.2 Atom-Counting Methods .................................................37 4.2.1 Kinetic Phosphorimetry Analysis ....................................37 4.2.2 Mass Spectrometry ...............................................38 4.2.2.1 Inductively Coupled Plasma-Mass Spectrometry .....................39 4.2.2.2 Thermal Ionization Mass Spectrometry .............................40 4.2.2.3 Accelerator Mass Spectrometry ...................................40 4.2.3 Summary of Analytical Methodologies, Minimum Detectable Concentrations, and Instrument Types .................................................41 5 Chemical and Physical Properties for Selected Radionuclides .......................43 5.1Americium ............................................................43 5.2Bismuth ..............................................................44 5.3Carbon ...............................................................44 5.4Cesium ...............................................................45 5.5Cobalt................................................................45 5.6 Hydrogen (Tritium) .....................................................46 5.7Iodine ................................................................47 5.8Iridium ...............................................................47 5.9Lead .................................................................48