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The Disposal of Activated Carbon from Chemical Agent Disposal Facilities (2009)
Board on Army Science and Technology (BAST)

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities

DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES

Committee to Examine the Disposal of Activated Carbon from the Heating, Ventilation, and Air Conditioning Systems at Chemical Agent Disposal Facilities

Board on Army Science and Technology

Division on Engineering and Physical Sciences

NATIONAL REASERCH COUNCIL OF THE NATIONAL ACADEMIES

THE NATIONAL ACADEMIES PRESS

Washington D.C.
www.nap.edu

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES Committee to Examine the Disposal of Activated Carbon from the Heating, Ventilation, and Air Conditioning Systems at Chemical Agent Disposal Facilities Board on Army Science and Technology Division on Engineering and Physical Sciences NATIONAL REASERCH COUNCIL OF THE NATIONAL ACADEMIES THE NATIONAL ACADEMIES PRESS Washington D.C. www.nap.edu

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This study was supported by Contract No. W911NF-08-C-0048 between the National Academy of Sciences and the U.S. Army. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project. International Standard Book Number-13: 978-0-309-13818-5 International Standard Book Number-10: 0-309-13818-3 Cover: The photograph on the cover shows part of a bank of activated carbon filter trays used for the HVAC systems at chemical agent disposal facilities. A detailed view of the structure and airflow through a filter tray can be seen in Figure 2-4. Courtesy of the U.S. Army Anniston Chemical Agent Disposal Facility, Anniston, Alabama. Limited copies of this report are available from Board on Army Science and Technology National Research Council 500 Fifth Street, N.W., Room 940 Washington, DC 20001 (202) 334-3118 Additional copies are available from The National Academies Press 500 Fifth Street, N.W. Lockbox 285 Washington, DC 20055 (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area) Internet, http://www.nap.edu Copyright 2009 by the National Academy of Sciences. All rights reserved. Printed in the United States of America

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities THE NATIONAL ACADEMIES Advisers to the Nation on Science, Engineering, and Medicine The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council. www.national-academies.org

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities COMMITTEE TO EXAMINE THE DISPOSAL OF ACTIVATED CARBON FROM THE HEATING, VENTILATION, AND AIR CONDITIONING SYSTEMS AT CHEMICAL AGENT DISPOSAL FACILITIES ROBERT A. BEAUDET, Chair, University of Southern California, Los Angeles TERESA J. BANDOSZ, City College of New York JOAN B. BERKOWITZ, Farkas Berkowitz and Company, Washington, D.C. HEREK L. CLACK, Illinois Institute of Technology, Chicago WILLARD C. GEKLER, ABS Consulting Inc., Los Alamitos, California LOREN D. KOLLER, Loren Koller and Associates, Corvallis, Oregon M. DOUGLAS LeVAN, Vanderbilt University, Nashville, Tennessee JOHN A. PENDERGRASS, Environmental Law Institute, Washington, D.C. KRISTA S. WALTON, Kansas State University, Manhattan WALTER J. WEBER, JR., University of Michigan, Ann Arbor YU-CHU YANG, Independent Consultant, Bel Air, Maryland Staff MARGARET N. NOVACK, Study Director HARRISON T. PANNELLA, Senior Program Officer NIA D. JOHNSON, Senior Research Associate JAMES C. MYSKA, Senior Research Associate ALICE V. WILLIAMS, Senior Program Assistant

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities BOARD ON ARMY SCIENCE AND TECHNOLOGY MALCOLM R. O’NEILL, Chair, Lockheed Martin Corporation (retired), Vienna, Virginia ALAN H. EPSTEIN, Vice-Chair, Pratt & Whitney, East Hartford, Connecticut DUANE ADAMS, Carnegie Mellon University (retired), Arlington, Virginia ILESANMI ADESIDA, University of Illinois at Urbana-Champaign RAJ AGGARWAL, Rockwell Collins, Cedar Rapids, Iowa SETH BONDER, The Bonder Group, Ann Arbor, Michigan JAMES CARAFANO, The Heritage Foundation, Washington, D.C. W. PETER CHERRY, Science Applications International Corporation, Ann Arbor, Michigan DARRELL W. COLLIER, U.S. Army Space and Missile Defense Command (retired), Leander, Texas JAY C. DAVIS, Lawrence Livermore National Laboratory (retired), Livermore, California PATRICIA K. FALCONE, Sandia National Laboratories, Livermore, California RONALD P. FUCHS, The Boeing Company, Seattle, Washington PETER F. GREEN, University of Michigan, Ann Arbor CARL GUERRERI, Electronic Warfare Associates, Inc., Herndon, Virginia JOHN J. HAMMOND, Lockheed Martin Corporation (retired), Fairfax, Virginia M. FREDERICK HAWTHORNE, University of Missouri, Columbia MARY JANE IRWIN, Pennsylvania State University, University Park ELLIOT D. KIEFF, Channing Laboratory, Harvard University, Boston, Massachusetts LARRY LEHOWICZ, Quantum Research International, Arlington, Virginia ROBIN MURPHY, Texas A&M University, College Station RICHARD R. PAUL, Consultant, Bellevue, Washington EDWARD K. REEDY, Georgia Tech Research Institute (retired), Atlanta DENNIS J. REIMER, DFI International (retired), Arlington, Virginia JONATHAN M. SMITH, University of Pennsylvania, Philadelphia MARK J.T. SMITH, Purdue University, West Lafayette, Indiana MICHAEL A. STROSCIO, University of Illinois, Chicago JUDITH L. SWAIN, University of California at San Diego, La Jolla WILLIAM R. SWARTOUT, Institute for Creative Technologies, Marina del Rey, California EDWIN L. THOMAS, Massachusetts Institute of Technology, Cambridge ELLEN D. WILLIAMS, University of Maryland, College Park JOSEPH YAKOVAC, JVM LLC, Hampton, Virginia Staff BRUCE A. BRAUN, Director CHRIS JONES, Financial Associate DEANNA P. SPARGER, Program Administrative Coordinator

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities Preface For more than two decades, the United States has been in the process of destroying its chemical agent and munitions stockpile. At this time, except for the nerve agent stored at a site where Congress has forbidden incineration and a few containers of legacy nerve agent GA (also known as tabun) at another site where they will soon be destroyed, the nation’s entire stockpile of nerve agents has been destroyed. The operating chemical agent disposal sites are in the process of destroying the remaining mustard agent munitions. The Army is now turning its attention to preparing for the closure of these facilities and the disposal of all the secondary wastes that have been stored on-site. One of the secondary wastes is an estimated total of more than 1,300 tons of activated carbon that has been used as an adsorptive medium to protect site personnel and adjacent communities from potential exposure to the agents. Some of this carbon (about 20 percent) has been exposed to chemical agents, although over time the adsorbed agents have reacted with the water also adsorbed on the carbon and formed hydrolysis products. In most cases, only trace amounts of agent remain on this carbon. The remaining carbon (about 80 percent) has not been exposed to agent but continues to be available for this purpose as one of the safety measures designed into the facilities. The U.S. Army’s Chemical Materials Agency (CMA) asked the National Research Council to convene a committee to study the disposal of all the carbon used at chemical agent disposal facilities. While this project seemed simple at first, it turned out to be complex. For one thing, the carbon is used in different kinds of filter units throughout the facility. Which of them are actually contaminated with agent? Most of the carbon is not contaminated and could be disposed of as ordinary hazardous waste. Another complication is that some of the mustard munitions contain high levels of mercury, a challenge for disposal. To address the mercury contamination requires changing the carbon in some filter units to sulfur-impregnated carbon, which will adsorb the mercury. Fortunately, the mercury-contaminated carbon is not expected to be exposed to agent unless there is a severe operational upset. Still another issue, already noted, is that the agents on the carbon degrade by reacting with the water adsorbed on the carbon and forming the usual hydrolysis products. But how much agent remains on the filters? Is this level below the waste control limits established by regulatory authorities? How can one measure the amounts of residual agent on the carbon given the very low parts-per-billion (ppb) level? How can one minimize or altogether prevent the re-formation of nerve agent GB (also known as sarin) during analysis? These are some of the issues that concerned the committee during this study, and they all have implications for how and where the activated carbon used in the course of destroying chemical agents can be disposed of. Fortunately, I believe the committee has “gotten its arms around this gorilla.” As its chair, I thank the members, who have worked as volunteers, for

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities their contributions to this report. They included traveling and attending meetings at various sites, followed by a series of virtual meetings to write the report. The committee is grateful to Timothy Garrett, who was the committee’s point of contact at CMA for the study. It was he who organized the presentations and hosted the meeting in Anniston, Alabama. Also, we thank all the Army participants, who gave up their time, traveled to meetings, and openly discussed their problems with us. Finally, we thank the staff of the Board on Army Science and Technology (BAST) for its support and logistical help. In particular we thank Margaret Novack, the program director for this project; Harrison Pannella, who reviewed the report for us in detail and provided sound advice; and Nia Johnson, who provided project research support. The BAST members, listed on page vi, were not asked to endorse the committee’s conclusions or recommendations, nor did they review the final draft of this report before its release, although board members with appropriate expertise may be nominated to serve as formal members of study committees or as report reviewers. The BAST was established in 1982 by the National Academy of Sciences at the request of the Army. It brings broad military, industrial, and academic experience and scientific, engineering, and management expertise to bear on Army technical challenges and other issues of importance to senior Army leaders. BAST also discusses potential studies of interest; develops and frames study tasks; ensures proper project planning; suggests potential committee members and reviewers for reports produced by fully independent, ad hoc study committees; and convenes meetings to examine strategic issues. Robert A. Beaudet, Chair Committee to Examine the Disposal of Activated Carbon from the Heating, Ventilation, and Air Conditioning Systems at Chemical Agent Disposal Facilities

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities Acknowledgment of Reviewers This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s (NRC’s) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report: Madan M. Bhasin, NAE, Dow Chemical Company (retired), Richard A. Conway, NAE, Union Carbide Corporation (retired), Gary S. Groenewold, Idaho National Laboratory, George W. Parshall, NAS, DuPont (retired), Danny Reible, NAE, University of Texas, William R. Rhyne, Consultant, William J. Walsh, Pepper Hamilton, LLP, and Calvin Willhite, State of California Environmental Protection Agency. Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by John R. Howell, NAE. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities Contents     SUMMARY   1 1   INTRODUCTION   8      Activated Carbon and Chemical Demilitarization,   8      Chemical Stockpile Disposal Program,   9      Overview,   9      Brief Description of the Chemical Agent Destruction Process,   10      Use of Carbon Filtration Systems at Chemical Agent Disposal Facilities,   11      Statement of Task,   11      Study Scope,   13      Organization of This Report,   13 2   USES AND MANAGEMENT OF ACTIVATED CARBON AT CHEMICAL AGENT DISPOSAL FACILITIES   15      Used Carbon Sources,   15      Management of Used Carbon,   20      References,   24 3   REGULATIONS GOVERNING CARBON DISPOSAL   25      Regulatory Framework and Considerations,   25      Overview of State-Specific Regulatory Requirements,   27      Alabama,   27      Arkansas,   28      Oregon,   28      Utah,   29      Commonalities and Differences Specific to Activated Carbon Practices and Permit Requirements,   29      Requirements Relating to Transportation,   31      General,   31      Existing Requirements for Transporting Carbon Off-site,   31      References,   32

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities 4   INTERACTIONS OF CHEMICAL AGENTS WITH ACTIVATED CARBON   33      Fundamentals of Adsorption,   33      Adsorption of Chemical Agents on Heating, Ventilation, and Air Conditioning Carbon,   35      Reactions of Chemical Agents on Activated Carbon,   37      GB Reactions,   37      VX Reactions,   39      Mustard Agent Reactions,   40      Summary of Studies of Agent Reactions on Carbon,   41      Methods for Determining Chemical Agent Loading on Activated Carbon,   42      References,   44 5   COMMERCIAL AND INDUSTRIAL PRACTICES FOR ACTIVATED CARBON MANAGEMENT   45      Commercial and Industrial Use of Activated Carbon,   45      Overview,   45      Mercury Removal as an Emerging Market for Activated Carbon,   45      Treatment and Disposal of Activated Carbon from Commercial and Industrial Applications,   46      References,   48 6   USE AND DISPOSAL OF SULFUR-IMPREGNATED CARBON FOR MERCURY ADSORPTION   49      Known Characteristics of Mustard Agent Stockpiles,   49      Fate of Mercury Within Thermal Destruction Processes at Chemical Agent Disposal Facilities,   50      References,   51 7   DISPOSAL OF CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES   52      Past Experience with Disposal of Used Activated Carbon,   52      Incineration of Used Carbon at JACADS,   52      Disposal of Used Carbon at ABCDF,   53      Disposal of Used Carbon at NECDF,   54      On-site Disposal of Exposed Carbon at Operating Disposal Facilities,   54      Current CMA Carbon Management Strategy,   55      Alternative Methods for Disposal of Carbon,   57      Use of Decontamination Solution for Off-site Disposal of Exposed Carbon,   57      Reactivation of Unexposed Carbon,   58      General Findings and Recommendations,   58      References,   60     APPENDIXES          A  Calgon Carbon Corporation General Carbon Acceptance Criteria for Reactivation   63      B  Committee Meetings, Site Visits, and Virtual Meetings   66      C  Biographical Sketches of Committee Members   68

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities Tables and Figures TABLES S-1   Summary of Sources and Estimated Inventories (in Pounds) of Carbon Exposed to Agent at CMA Incineration Sites During Operations and Closure,   2 S-2   Summary of Sources and Estimated Inventories (in Pounds) of Unexposed Carbon Used at CMA Incineration Sites During Operations and Closure,   3 S-3   Current Status of Permit Requirements for Shipping Carbon Off-site from Chemical Agent Disposal Facilities,   3 2-1   Uses of Activated Carbon Filters at Chemical Agent Disposal Facilities,   21 2-2   Estimated Carbon Waste Inventories (in Pounds) for CMA Chemical Agent Disposal Facilities as of September 29, 2008,   22 2-3   Summary of Sources and Estimated Inventories (in Pounds) of Carbon Exposed to Agent at CMA Incineration Sites During Operations and Closure,   22 2-4   Summary of Sources and Estimated Inventories (in Pounds) of Unexposed Carbon Used at CMA Incineration Sites During Operations and Closure,   22 2-5   Pertinent Physical Properties of the Chemical Agents and Mercury,   23 3-1   Current Status of Permit Requirements for Shipping Carbon Off-site from Chemical Agent Disposal Facilities,   31 4-1   Agent Loadings on Cocoanut Activated Carbon,   35 4-2   Analytical Results of HVAC and PFS Carbon Samples Collected from ANCDF in January 2007,   36 4-3   Chemical Formulas for Mustard Agent and Its Hydrolysis Products,   41 4-4   Analysis of GB and VX on Carbon and Method Detection Limits (MDLs),   43 7-1   Agent Mass Limits per Drum for Off-site Shipment of Secondary Waste,   57 FIGURES 1-1   Schematic of the baseline incineration system,   10 1-2   Sources of used carbon in a typical chemical agent disposal facility,   12

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities 2-1   The nine activated carbon filter units for the MDB HVAC system,   16 2-2   Schematic representation of airflow through the six filter banks that make up each MDB HVAC filter unit,   17 2-3   A filter tray,   17 2-4   Airflow path through a filter tray,   18 2-5   PFS filter unit,   18 2-6   Schematic of the PAS/PFS flow configuration including the PFS filter unit,   19 2-7   Schematic representation of the combustion gas flow path through the PFS,   19 2-8   An M-40 protective mask with the filter C-2 canister attached,   20 2-9   A 95-gallon drum for storage of used carbon filter trays,   23 2-10   Vestibule on the side of an MDB HVAC unit,   23 4-1   Mass transfer zone in a carbon adsorption bed,   34 4-2   Water adsorption isotherms on activated carbons made from different types of wood (W, W1, and W2) and coals (N, N1, and N2) at 25°C,   35 4-3   Phosphorus-31 magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of 10 weight percent sarin (GB) on humidified (13 weight percent water) activated carbon over time: initial and after 6, 13, and 16 days, left to right,   38 4-4   MAS NMR spectra for 10 weight percent nerve agent VX absorbed on humidified (13 weight percent water) carbon, left to right: initial and at 24 days showing heterogeneous autocatalytic hydrolysis of VX over 24 days, left to right,   39 5-1   General schematic of the fate of spent activated carbon from commercial and industrial sources,   48 5-2   Calgon Carbon’s process for reactivation of spent carbon,   48

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities Abbreviations and Acronyms ABCDF Aberdeen Chemical Agent Disposal Facility ACAMS automatic continuous air monitoring system ACS agent collection system ADEM Alabama Department of Environmental Management ADEQ Arkansas Department of Environmental Quality AEGL acute exposure guideline level ANCDF Anniston Chemical Agent Disposal Facility BGCAPP Blue Grass Chemical Agent Destruction Pilot Plant BTRA boundary transportation risk assessment CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CH mustard chlorohydrin CH-TG sulfonium ion CMA Chemical Materials Agency CMS carbon micronization system CWC Chemical Weapons Convention DAAMS depot area air monitoring system DFS deactivation furnace system DOT Department of Transportation DPE demilitarization protective ensemble ECBC U.S. Army Edgewood Chemical and Biological Center EMPA ethyl methylphosphonic acid EONCs enhanced on-site containers EPA U.S. Environmental Protection Agency GA nerve agent GAC granulated activated carbon GB nerve agent (sarin) GC gas chromatography GPL general population limit H mustard agent HCl hydrochloric acid HD distilled mustard agent HF hydrofluoric acid Hg mercury HT distilled mustard mixed with bis(2-chloroethylthioethyl) ether HVAC heating, ventilation, and air conditioning IMPA isopropyl methylphosphonic acid JACADS Johnston Atoll Chemical Agent Disposal System LDR land disposal restrictions LIC liquid incinerator

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Disposal of Activated Carbon from Chemical Agent Disposal Facilities MAS magic angle spinning MDB munitions demilitarization building MDL method detection limit MPF metal parts furnace MS mass spectrometry MWI municipal waste incinerator NaOH sodium hydroxide NECDF Newport Chemical Agent Disposal Facility NMR nuclear magnetic resonance NRC National Resource Council ODEQ Oregon Department of Environmental Quality ONCs on-site containers OTS off-gas treatment system PAC powdered activated carbon PAS pollution abatement system PBCDF Pine Bluff Chemical Agent Disposal Facility PCAPP Pueblo Chemical Agent Destruction Pilot Plant PCC permit compliance concentration PFS PAS filtration system ppb parts per billion ppm parts per million ppmw parts per million by weight RCRA Resource Conservation and Recovery Act STEL short-term exposure limit STL short-term limit (no time component specified) SwRI Southwest Research Institute TCLP toxic chemical leaching procedure TG thiodiglycol TOCDF Tooele Chemical Agent Disposal Facility TRA transportation risk assessment TSDF treatment, storage, and disposal facility UDEQ Utah Department of Environmental Quality UMCDF Umatilla Chemical Agent Disposal Facility VSL vapor screening level VX nerve agent VX-pyro diethyl dimethylpyrophosphonate WAP waste analysis plan WCL waste control limit