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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
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1
Introduction

DESCRIPTION OF THE CHEMICAL AGENT AND MUNITIONS STOCKPILE

For more than 50 years, the United States has maintained a stockpile of chemical agents and munitions distributed among eight sites in the continental United States and at Johnston Atoll in the Pacific Ocean. Two basic types of chemical agents comprise the stockpile: neurotoxic (nerve) agents and mustard (blister) agents. Both types are frequently, and erroneously, referred to as "gases" even though they are liquids at normal temperature and pressure.1

The nerve agents include organic phosphorus compounds designated as VX, GB (sarin), and GA (tabun). These chemicals present a significant toxic hazard because of their action on the nervous systems of humans and animals through inhibition of the acetylcholinesterase enzyme. VX is more acutely toxic than GB, but the latter represents a greater potential hazard because of its higher volatility (about the same as water) and, thus, the greater likelihood of being inhaled. Chronic health effects and cancer from low-level exposures have not been associated with nerve agents or with chemically (and toxicologically) similar commercially available organic phosphorus insecticides (Leffingwell, 1993). Only short-term symptoms have been documented in individuals who have survived exposure to nerve agents.

The mustards (designated H [nondistilled mustard], HD [distilled mustard], and HT [thickened mustard]) do not present significant acute lethal hazards. Their principal effect is severe blistering of the skin and mucous membranes. They have been implicated as possible carcinogens, however, and may present a cancer hazard to individuals suffering acute exposure (Leffingwell, 1993; IOM, 1993). Estimates of induced cancers from accidental agent exposures only apply to mustard agents.

Once chemical agents are fully dispersed, they do not tend to persist in the environment because of their high chemical reactivity, particularly with water. However, in extremely dry desert climates, they can persist for a considerable period of time (U.S. Army, 1988).

The chemical agents in the U.S. stockpile are stored in a variety of containers, including bulk (ton) containers, rockets, projectiles, mines, bombs, cartridges, and spray tanks. Figure 1-1 summarizes the stockpile configuration for the eight continental U.S. sites by agent, munition, and containment system prior to the start of agent destruction operations at the Tooele Chemical Agent Disposal Facility (TOCDF) (NRC, 1997).

CALL FOR DISPOSAL

Chemical Stockpile Disposal Program

Because of the age of the stockpiled chemical weapons, their lack of utility as effective weapons or deterrents, the continuing costs of maintenance, and the potential for accidental release, the United States and other countries have strong incentives to dispose of them. In 1985, Congress enacted Public Law 99-145 to initiate the process of eliminating the U.S. chemical weapons stockpile with an expedited program to dispose of

1  

 The stockpile (the subject of the Army's Chemical Stockpile Disposal Program) consists of both bulk containers of nerve and blister agents and munitions, including rockets, mines, bombs, cartridges, projectiles, and spray tanks loaded with nerve or blister agents. Buried chemical warfare material, recovered chemical warfare material, binary weapons (in which two nonlethal components are mixed after firing to yield a lethal nerve agent), former production facilities, and miscellaneous chemical warfare material are not included in the stockpile. The disposition of these five classes of materials is the subject of the separate Non-Stockpile Chemical Material Program. Information on the Army's overall chemical material disposal programs is available at http://www-pmcd.apgea.army.mil/

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

Figure 1-1 Location and size (percentage of original stockpile) of eight continental U.S. storage sites.

Source: OTA, 1992; NRC, 1997.

M55 rockets. These munitions raise special concerns because they are aging and because they contain agent, explosives, and propellants in an integrated configuration (as propellants age, stabilizer components degrade—increasing the potential for autoignition). In 1992, Congress enacted Public Law 104–484, which directed the Army to dispose of the entire unitary2 chemical agent and munitions stockpile by December 31, 2004. Congress also directed that the Chemical Stockpile Disposal Program (CSDP) be implemented in a manner that ensured maximum protection of workers, the public, and the environment.

Chemical Weapons Convention

The CSDP has evolved in parallel with worldwide efforts to establish international control of chemical agent precursors and eliminate chemical agents and munitions. Over the course of several decades, a broad and complex agreement known as the Chemical Weapons Convention (CWC) was negotiated. Since 1993, the CWC has been signed by 165 countries and ratified by more than 100. The convention went into effect on April 29, 1997, six months after 65 countries had ratified it. Since then, the United States, which was actively involved in negotiating the CWC agreement, and Russia, the world's largest holder of chemical agents and munitions, have also ratified it.

The CWC prohibits the development, production, acquisition, stockpiling, retention, transfer, or use of chemical weapons. Article IV requires that signatories destroy chemical weapons and any special facilities for their manufacture within 10 years, (by April 29, 2007). Destruction of chemical weapons is defined as "a process by which chemicals are converted in an essentially

2

The term unitary refers to a single chemical loaded in munitions or stored as a lethal material. More recently binary munitions have been produced, in which two relatively safe chemicals are loaded into separate compartments to be mixed to form a lethal agent after the munition is fired or released. The components of binary munitions are stockpiled separately, in separate states They are not included in the present Chemical Stockpile Disposal Program. However, under the Chemical Weapons Convention of 1993, they are included in the munitions that will be destroyed.

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

irreversible way to a form unsuitable for production of chemical weapons, and which, in an irreversible manner, renders munitions and other devices unusable as such" (Smithson, 1993). The method of destruction is to be determined by each country, but the manner of destruction must ensure public safety and protect the environment.

Selection and Development of the Baseline Incineration System

In the early 1980s, the Army investigated a number of strategies and technologies for the destruction or disposal of chemical weapons. Among these were chemical destruction ("neutralization"), ocean disposal (now banned by federal law), stockpile consolidation with subsequent destruction, and disassembly followed by component incineration. The Army then selected incineration as the preferred technology for stockpile disposal. The National Research Council (NRC) Committee on Demilitarizing Chemical Munitions and Agents was formed in August 1983 to review the status of the stockpile and to assess the available disposal technologies. In that committee's final report in 1984, incineration was endorsed as an adequate technology for the safe disposal of chemical warfare agents and munitions (NRC, 1984).

Pursuant to the enactment of Public Law 99–145, the Army began the development of components of the baseline incineration system at the Chemical Agent Munitions Disposal System (CAMDS) facility at Deseret Chemical Depot (DCD), formerly Tooele Army Depot, Utah. Construction and systemization of the first fully integrated baseline incineration system, the Johnston Atoll Chemical Agent Disposal System (JACADS), was completed in July 1990 on Johnston Island, located in the Pacific Ocean approximately 700 miles southwest of Hawaii. The JACADS facility has a two-fold mission:

  • to destroy the chemical agents and munitions stored there

  • to serve as a demonstration facility for the baseline incineration system

INCINERATION SYSTEM AT THE TOOELE CHEMICAL AGENT DISPOSAL FACILITY

The incineration system at the TOCDF represents a second-generation baseline system that incorporates improvements based on operating experience at the JACADS facility, advances in technology, and recommendations by the Committee on the Review and Evaluation of the Army Chemical Stockpile Disposal Program (Stockpile Committee), the successor to the Committee on Demilitarizing Chemical Munitions and Agents. The design was also based on the concept that the performance and safety of disposal are greatly enhanced if stockpile feed materials are separated into distinct streams of agent, energetic materials, metal parts, and dunnage (packing, activated carbon, and other waste material) prior to disposal treatment. A schematic drawing of the TOCDF incineration system is shown in Figure 1–2 (see Appendix A for a description of specific features of the TOCDF incineration system). Systemization (preoperational) testing at TOCDF began in August 1993, and agent operations began on August 22, 1996. Prior to the start of agent operations, a quantitative risk assessment (QRA) and a health risk assessment (HRA) were conducted (U.S. Army, 1996a; Utah DSHW, 1996). 3

In the TOCDF baseline system, feed materials are separated inside a building that has areas capable of withstanding explosions. The atmospheric pressure in these and other areas where agent may potentially be present is controlled to be lower than the ambient atmospheric pressure to prevent leakage from the building to the outside atmosphere. Agents are removed from munitions and containers via remote control by two methods. Most containers are simply mechanically punched open and drained. Munitions, which also contain energetics (explosives/propellants), are mechanically disassembled and drained. These processes yield three material streams: agent, energetics, and metal parts. Energetics and metal parts may be

3  

 The TOCDF QRA estimates the risk to the public and to workers from accidental releases of chemical agent associated with all activities during storage at DCD and throughout the disposal process at the TOCDF The HRA, which was conducted by the Utah Division of Solid and Hazardous Waste (Department of Environmental Quality), was a screening analysis to estimate possible off-site human health risks associated with exposure to airborne emissions from the TOCDF under normal and upset conditions. The HRA also estimates risks to wildlife and the environment

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

Figure 1-2 Schematic drawing of the TOCDF incineration system.

Source: U.S. Army, 1988; NRC, 1994b, 1994c.

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

contaminated by residual agent, but the vast majority of agent (95 percent or more) is usually recovered during the draining procedure. This material separation is a major safety feature of the TOCDF baseline system, which has parallel disposal systems for the treatment of these very different material streams.

At the TOCDF, agents are pumped to and destroyed in one of two specially designed liquid incinerators (LICs). Each LIC consists of a primary and secondary combustion chamber, and is followed by a pollution abatement system (PAS) consisting of a quick quench that saturates the gas stream, a venturi scrubber to control particulates, a tower scrubber to remove gaseous contaminants, and a demister to minimize water droplet carryover to the stack. Agent flow is stopped if the combustion chamber temperature drops below 2,550°F. Energetics are burned in a rotary kiln deactivation furnace system (DFS); exhaust gases are sent to an afterburner and then treated by a PAS before release to the atmosphere. Metal parts are decontaminated by heating in a metal parts furnace (MPF) to 1,000°F for a minimum of 15 minutes to vaporize and burn any residual agent; exhaust gases are sent to an afterburner and then to a PAS.

Agent compounds contain various inorganic elements that result in significant acid gas incineration products. Acidic gases in the discharge streams are scrubbed in the PAS of each furnace with alkali solutions to form salts. In the original plan, these wet salts, or brine, were to be processed in a brine reduction area (BRA) and the resultant dry salts stored for later disposal in hazardous-waste landfills. However, brine from the TOCDF is now shipped off site to a hazardous-waste disposal facility.

According to the original plan, contaminated and uncontaminated packing materials and miscellaneous waste, or dunnage, were to be burned in a dunnage furnace (DUN) and the exhaust gases discharged through a separate stack without acid gas scrubbing because only trace amounts of agent or other acid-producing species were expected to be present. Current practice at the TOCDF is to dispose of dunnage that is not contaminated with agent off site through normal waste-handling processes. Some agent-contaminated materials are decontaminated and disposed of as hazardous waste. Used activated carbon from the facility's air filtration system is a major waste component originally slated to be disposed of in the DUN. An alternate procedure for incinerating this material in the DFS is scheduled for testing in 2001.

Two auxiliary material streams are also processed: decontamination fluids are incinerated in the secondary combustion chamber of the LIC; and ventilation air is passed through banks of activated carbon filters to remove any trace contaminants.

Baseline monitoring systems are used to detect agent release and to monitor adherence to environmental requirements. The agent monitoring system consists of a combination of the automatic continuous air monitoring system (ACAMS) and the depot area air monitoring system (DAAMS). The ACAMS detects immediate threats with a three- to eight-minute response time for agent levels at 20 percent of the permissible eight-hour exposure concentration for workers. The DAAMS, which provide a much more sensitive and definitive measurement, has a slower response time because it requires transporting collection tubes to a central laboratory for analysis. An ACAMS alarm from monitoring the exhaust flow through the PAS results in an immediate shutoff of agent feed. Because the less selective ACAMS field monitors sometimes produce false alarms for certain nonagent emissions, DAAMS laboratory analyses are used to confirm or disprove ACAMS alarms and to document environmental compliance.

ROLE OF THE COMMITTEE ON REVIEW AND EVALUATION OF THE ARMY CHEMICAL STOCKPILE DISPOSAL PROGRAM

Concurrent with the beginning of construction of the baseline incineration facility at JACADS in 1987, the Army requested that the NRC review and evaluate the CSDP in order to provide advice and counsel. The NRC established the standing Stockpile Committee at that time to perform these tasks, beginning with a study of operational verification testing at JACADS, which was completed in March 1993. Several reports issued by the committee (e.g., Recommendations for the Disposal of Chemical Agents and Munitions [NRC, 1994a] and Review of Systemization of the Tooele Chemical Agent Disposal Facility [NRC, 1996a]) concluded that the baseline incineration system was an adequate and safe means of disposing of the chemical weapons stockpile (see Appendix B for a complete list of Stockpile Committee reports).

Composition of the Stockpile Committee

Since its inception in 1987, the Stockpile Committee has exercised an advisory and oversight role over the Army's CSDP. Over the years, the Stockpile Committee has adjusted the composition of its membership to

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

maintain a balance of disciplines necessary to meet the task at hand. Current members have expertise in analytical chemistry; biochemical engineering; chemistry; chemical engineering; chemical industry management; combustion engineering; community health and urban studies; environmental health policy; environmental restoration; health risk assessment and environmental toxicology; mechanical engineering; monitoring and instrumentation; risk assessment, management, and communication; statistics and incinerator performance analysis; toxicology; and waste treatment and minimization.

OVERVIEW OF RELEVANT NRC RECOMMENDATIONS

Table 1-1 is a summary of recommendations from past NRC reports that are relevant to the present study. In the 1994 NRC report, Recommendations for the Disposal of Chemical Agents and Munitions (Recommendations report), the Stockpile Committee established its general criterion for evaluating CSDP activities. This criterion is included in the first recommendation (subsequently referred to as [RC-1]: ''The Chemical Stockpile Disposal Program should proceed expeditiously and with technology that will minimize total risk to the public at each site" (NRC, 1994a).

Although the minimization of public risk continues to be the committee's major concern, the total risk is dependent on a number of factors:

  • integrity of facility design, construction, operation, and maintenance

  • a safety culture throughout the organization

  • qualified, well trained, highly motivated managers and workers

  • current, detailed safety analyses

  • positive working interactions with regulatory agencies, emergency response services, community groups, and the general public

The 1996 NRC report, Review of Systemization of the Tooele Chemical Agent Disposal Facility (Systemization report), which was published several months before the start of agent operations at the TOCDF, contained 18 specific recommendations organized by the timing of the start of agent operations (NRC, 1996a). However, for the purposes of the present report, they are considered topically. A 1996 letter report, Public Involvement and the Army Chemical Stockpile Disposal Program, contained two recommendations (NRC, 1996b). In the 1997 NRC report, Risk Assessment and Management at Deseret Chemical Depot and the Tooele Chemical Agent Disposal Facility (Risk Assessment and Management report), 10 additional recommendations were made (NRC, 1997). In Table 1-1, the Recommendations report is designated [RC]; the Systemization report is designated [S]; the Risk Assessment and Management report [R]; and the Public Involvement report [PI]. A complete list of TOCDF-related recommendations is presented in Appendix C.

PURPOSE OF THIS REPORT

This report reviews the status of the CSDP with respect to earlier recommendations made by the Stockpile Committee. The primary objectives of this report are to assess the Army's progress and to acknowledge actions that satisfy prior recommendations, to identify recommendations that require further action, and to provide additional recommendations for improving overall performance at the TOCDF after more than two years of agent disposal operations. Although the focus of this report is on the TOCDF, some findings and recommendations apply to other sites and the CSDP as a whole. The statement of task concerning this report follows:

Statement of Task

The NRC study will accomplish the following:

  • Gather and assess data and information from the Tooele Chemical Agent Disposal Facility (TOCDF) on systems performance and plant operations, e.g., incineration trial burns, brine reduction area testing and certification, slag removal system operations, monitoring systems operations, and other performance characteristics.

  • Assess progress in the area of safety and risk management, e.g., establishment of a safety culture, establishment of safety performance goals, implementation of high quality, adequately staffed safety management systems, and implementation of other elements important to a sound risk management program.

  • Evaluate and assess the Army's actions and programs designed to enhance public and community

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

TABLE 1-1 NRC Recommendations Addressed in This Report

Prior Recommendation

Area(s) Addressed by Recommendation

Chapter in Which Recommendation Is Discussed

RC-1

Program-wide risk reduction

2, 3, 4

S-1

Implementation of a safety program

3, 4

S-2

Incorporation of safety and environmental goals into award fees

4

S-3

Completion of QRA, resolution of safety-related issues

3

S-4

Improved public interactions and communications

5

S-5

Emergency preparedness training

5

S-6

Completion and practice of emergency preparedness plans

5

S-7

Completion of emergency-preparedness communications system for Tooele site

5

S-8

Completion of Army preoperational survey

2

S-9

Attainment of LIC 99.9999% DRE

2

S-10

Safety management

4

S-11

Completion of RCRA and TSCA trial burns

2

S-12

BRA certification; dunnage disposal

2

S-13

LIC slag removal

2

S-14

Completion of risk management plan (RMP)

3

S-15

Risk assessment integration

3

S-16

"Near misses" tracking and safety

3

S-17

Improvements in monitoring

2

R-1

Updating of QRA, HRA

3

R-2

Development and review of program-wide site-specific QRAs and HRAs

3

R-3

Update of QRA methodology manual

3

R-4

Inclusion of "safety culture" in Guide

4

R-5

Definitions of risk management roles and responsibilities in Guide

4

R-6

Inclusion of public involvement in RMP

5

R-7

Tracking of CMP performance

5

R-8

Understanding of risk assessment by workers, etc.

3

R-9

Implementation and updating of RMP

3, 4, 5

PI-1

Commitment of CSDP to public involvement

5

PI-2

Coordination of CSDP, CSEPP, public affairs, and RMP

3, 5

Legend: RC = Recommendations for the Disposal of Chemical Agents and Munitions (NRC, 1994a); S = Review of Systemization of the Tooele Chemical Agent Disposal Facility (NRC, 1996a); R = Risk Assessment and Management at Deseret Chemical Depot and the Tooele Chemical Agent Disposal Facility (NRC 1997); and PI = Public Involvement and the Army Chemical Stockpile Disposal Program (NRC, 1996b). See Appendix B for a complete list of reports by the NRC Stockpile Committee.

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×

interactions on issues of mutual concern, e.g., risk reduction, change management, emergency management, etc.

  • Extract valuable lessons learned and their programmatic implications.

  • Provide recommendations that the committee believes are needed to enhance the overall Chemical Stockpile Disposal Program at the TOCDF and at other sites.

In performing this assessment, the entire Stockpile Committee visited the TOCDF in March 1997 and met with TOCDF staff in Salt Lake City in February 1998 (see Table 1–2). A working group of the committee also visited the site on December 9, 1997, and March 11, 1999. This report is based on those visits, prior visits, a review of reports and briefings by the Army and other groups, and the committee's extensive knowledge of the CSDP and the construction and systemization of the TOCDF.

This chapter has provided a brief description of the TOCDF facilities and the CSDP. Chapter 2 assesses systems performance and plant operations. Chapters 3 and 4 discuss risk assessment and risk management and safety issues, respectively. Chapter 5 reviews the relationships between the TOCDF (which is operated by Edgerton, Germerhausen and Grier [EG&G] Defense Materials Incorporated, an Army contractor, and the

TABLE 1–2 Site Visits and Briefings

TOCDF Site Visits

(1997–1999)

Committee Attendance

March 1997

full committee

July 1997

working group

December 1997

working group

February 1998

new members

TOCDF Briefings

(1997–1999)

 

March 6, 1997

full committee

June 19, 1997

full committee

September 18, 1997

full committee

February 26, 1998

full committee

June 25, 1998

full committee

September 24, 1998

full committee

January 7, 1999

full committee

March 18, 1999

full committee

office of the U.S. Army Program Manager for Chemical Demilitarization [PMCD]) and relevant government and community groups. Committee findings and recommendations are presented in Chapter 6.

Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
Page 11
Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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Suggested Citation:"1 Introduction." National Research Council. 1999. Tooele Chemical Agent Disposal Facility: Update on National Research Council Recommendations. Washington, DC: The National Academies Press. doi: 10.17226/9727.
×
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This report reviews the status of the U.S. Army Chemical Stockpile Disposal Program (CSDP) operations at Tooele, Utah, with respect to previous recommendations and observations made by the National Research Council (NRC) Committee on Review and Evaluation of the Army Chemical Stockpile Disposal Program (Stockpile Committee). The committee recognizes actions that have satisfied recommendations, identifies recommendations that require further action, and provides additional recommendations for improving the overall CSDP performance at the Tooele Chemical Agent Disposal Facility (TOCDF), Tooele, Utah, and other sites.

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