Review of the Army Non-Stockpile Chemical Materiel Disposal Program: Disposal of Chemical Agent Identification Sets (1999)

The National Research Council (NRC) Committee on Review of the Non-Stockpile Chemical Materiel Disposal Program has been requested to review and provide recommendations on the Army's plans for disposing of chemical agent identification sets (CAIS), a relatively small component of the Non-Stockpile Chemical Materiel Disposal Program. These plans are described in the Army's report to Congress, which concludes in part that the "law and its interpretation impose the major obstacles limiting options for the transportation and disposal of CAIS" (U.S. Army, 1998, p. iv). The report also states that the Army has interpreted the legal and regulatory restrictions to mean that "CAIS sets [sic] cannot be processed commercially as hazardous waste due to the current statutory and regulatory framework for handling chemical agent and munitions" (U.S. Army, 1998, p. iii). These broad legal interpretations are a major reason that disposal costs are estimated to be very high.

One of the primary factors that the Army believes contributes to the high costs of CAIS disposal is the legal restriction on the use of federal funds to transport or dispose of lethal chemical warfare agents (50 U.S.C. § 1512). This restriction precludes the transport to or from any military installation or the disposal of chemical warfare agents in the United States until the following actions have been taken:

• U.S. Department of Defense (DOD) has determined that the transportation or testing is in the interests of national security.

• DoD has notified the secretary of health and human services, who has reviewed the potential hazards to public health and safety and recommended precautionary measures.

• DoD has implemented the precautionary measures recommended above. Even if the recommendation prevents the proposed transportation or disposal, the President may determine that overriding considerations of national security require that transportation or disposal proceed.

• DoD has notified: (1) the president of the Senate and the speaker of the House of reesentatives at least 10 days before transportation commences and at least 30 days before testing or disposal commences; and (2) the governor of any state through which chemical warfare agents will be transported.

Similarly, 50 USC § 1512a requires that "chemical munitions" that are "not part of the chemical weapons stockpile" be transported to the nearest chemical munitions stockpile storage facility that has appropriate permits for receiving the item if (1) the

secretary of defense considers transportation necessary; and (2) transportation will not pose a significant risk to public health and safety.

In disposing of chemical warfare materiel (CWM), the Army must use "adequate and safe facilities" designed "solely for the destruction of lethal chemical agents and munitions" (50 U.S.C. 1521(c)(1)(B)). However, these facilities may not be used for any purpose "other than the destruction of lethal chemical weapons and munitions" (50 U.S.C. 1521(c)(2)).

Both the Non-Stockpile Chemical Materiel Program and the Chemical Stockpile Disposal Program must be conducted within a complex legal and regulatory framework that has delicate international implications. From a regulatory point of view, some of the questions are familiar (e.g., the level of acceptable risk), and some are unique (e.g., the required notification of Congress and the affected state[s]).

The .regulation of some chemicals varies depending on how they are used. For example, phosgene in a chemical weapon is regulated as a chemical warfare agent. Phosgene in a container at a facility may be regulated as non-stockpile chemical materiel or a toxic chemical ("industrial chemical") subject only to commercial disposal requirements. Interpretation of the legal status of CAIS, which dictates the disposal method, is based more on the judgment of the Army' s Office of General Counsel than on explicit language in the statutes.

The safe disposal of non-stockpile chemical agents raises important environmental policy issues, some of which are listed below:

• What is the appropriate process for determining the type and location of disposal?

• How transparent should the decision-making process be?

• What concentration of these chemical agents in ambient air is considered "safe"?

• What are the equities of disposing of chemical agents in one state when they were discovered in a different state?

• What are the appropriate roles of federal, state, and local authorities?

Both the stockpile and non-stockpile chemical materiel disposal programs have also been affected by the military's administrative and organizational framework, which is distinctly different from the commercial waste disposal framework.

To understand the dilemma facing the Army requires an understanding of the applicable legal framework, the Army's policy on the disposal of CAIS, and alternative legal interpretations. Several statutory provisions have been enacted in the last several years to implement the stockpile and non-stockpile chemical materiel (disposal) programs:

• The Army currently interprets the statutory scheme to mean that "CAIS cannot be handled commercially as hazardous waste" (U.S. Army, 1998, p. iii) because CAIS are considered CWM (U.S. Army, 1997, p. 1).

• The Army interprets 50 U.S.C. § 1512a (which applies to "chemical munitions" that are not part of the chemical weapons stockpile) as precluding the movement of CAIS to commercial treatment, storage, and disposal facilities (U.S. Army, 1997, p. 5).

• CAIS are in included in the definition of recovered CWM in Army Regulation 50-6.

• The Army has concluded that "mustard and Lewisite in any form, including CAIS, will be considered 'lethal chemical agents and munitions' for the purpose of destruction" (U.S. Army, 1998, p. iv).

• The Army interprets the intent of Congress to be that the stockpile chemical agent destruction facilities not be used to destroy CAIS (U.S. Army, 1998, p. 4).

CAIS are difficult to categorize pursuant to the definitions in the Chemical Weapons Convention (CWC) and existing statutes. The difficulty is compounded by the lack of clarity in the congressional language and the fragmentary development of this statutory scheme. Several similar, but different, statutory definitions could apply to CAIS and, indeed, to much of the non-stockpile and stockpile chemical agents.

Similar, but slightly different, terms (lethal chemical warfare agent, lethal chemical agents and munitions, lethal chemical weapons and munitions, chemical agents and munitions, chemical munitions, chemical weapons, toxic chemicals, chemical warfare materiel, and chemical agents) are used in the relevant or related statutes or guidance. Unfortunately, Congress has not specifically defined some of these terms (e.g., lethal chemical warfare agent and chemical munitions) making it difficult to decipher their meaning or Congress' intent.

However, some definitions are included in the statutes or can be deduced from the statutory language. A chemical agent and munition means "an agent or munition that, through its chemical properties, produces lethal or other damaging effects on human beings, except such term does not include riot agents, chemical herbicides, smoke and other obscuration materials" (50 U.S.C. § 1521(j)(1)). The term lethal chemical agent and munition means "a chemical agent or munition that is designed to cause death, through its chemical properties, to human beings in field concentrations" (50 U.S.C. § 1521 (j)(2)). Congress seemed to indicate that the term "any lethal chemical . . . agent" was "not intended to apply to use of . . . chemical. . . materials used for. . . test evaluation."¹ Similarly, chemical warfare materiel is defined in Army guidance documents as an ''item configured as a munition containing a chemical substance that is intended to kill, seriously injure, or incapacitate a person through its physiological effects" (U.S. Army, 1997, p. 1).

In the CWC Implementation Act of 1998, a chemical weapon is defined as follows:

• a toxic chemical and its precursors, except where intended for a purpose not prohibited under this chapter as long as the type and quantity is consistent with such a purpose

• a munition or device specifically designed to cause death or other harm through toxic properties of those toxic chemicals specified in subparagraph (a) which would be released by a result of the employment of such munition or device.

• any equipment specifically designed for use directly in connection with the employment of such munition or device²

Toxic chemical means any "chemical which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals. The term includes all such chemicals, regardless of their origin or of their method of production, and regardless of whether they are produced in facilities in munitions or elsewhere."³

Therefore, it appears that a chemical agent is any substance that produces lethal or other damaging effects on humans. Lethal chemical agent appears not to be intended to include chemical agents used for testing. The definition of munition or warfare materiel seems to be inextricably linked to the intent in designing the device.

There is no debate that (1) the chemicals in CAIS are toxic chemicals; (2) these chemicals can cause temporary incapacitation or permanent harm to humans under some exposure scenarios; (3) CAIS were designed for training purposes, not warfare; (4) CAIS are not munitions; and (5) the volume of, and therefore the risk from, the toxic chemicals in CAIS is less than that of the other materiel in the stockpile and non-stockpile chemical materiel (disposal) programs.

Thus, a possible interpretation is that CAIS are not lethal chemical warfare agents or CWM. In this confusing statutory framework and for reasons not apparent in Army policy documents, the Army has strictly construed the statutory scheme and seems to treat CAIS as a lethal chemical warfare agent and/or CWM. The implication is that CAIS should be considered a munition or warfare materiel because the contents could be converted into a weapon. The Environmental Protection Agency (EPA) simply cross-references the definition of chemical agents and munitions in 50 U.S.C. section 1521(j)(1)(EPA, 1997, p. 6624). This confusion has impeded the progress of CAIS disposal.

The Resource Conservation and Recovery Act (RCRA) provides cradle-to-grave regulation of hazardous waste, including the generation, storage, transportation, disposal, and treatment. RCRA includes a corrective action program that requires the cleanup of past or present contamination at the nearly 5,000 or so facilities nationwide that handle, store, transport, or dispose of hazardous waste (in essence, facilities with RCRA permits or interim status). Thus, if CAIS are also interpreted to be hazardous wastes, they must be handled, transported, disposed of, or treated in compliance with EPA's hazardous waste regulations. These requirements, therefore, would dictate the minimum requirements for the storage, disposal, and treatment of CAIS.

EPA has technically reviewed the chemical agents in the stockpile disposal program (the same chemicals that are in the non-stockpile program) and has concluded that these agents, including those in CAIS, are hazardous wastes because they exhibit at least one of

the characteristics described in EPA's hazardous waste regulations. ⁴ EPA also observed that chemical agents "are more akin to other types of chemical wastes that RCRA typically regulates than are conventional weapons" (which are also covered by the munitions rule) (EPA, 1997, p. 6638). EPA representatives confirmed to the committee the interpretation that recovered CAIS should be considered hazardous waste. Thus, EPA already considers that the federal hazardous waste regulatory disposal requirements are appropriate for handling chemical agents safely. Therefore, nothing in the federal hazardous waste regulations prohibits the processing of CAIS commercially as hazardous waste.

Requirements for the disposal of hazardous wastes may not be specified in the technical requirements in regulations. In some circumstances, location-specific or chemical-specific permit conditions are developed and made legally binding through the permit process. In other cases, permit writers use guidance and policy documents to add requirements. Unique permit conditions are appropriate if a site-specific risk evaluation indicates that the condition is necessary to protect human health or the environment.

The question of whether unique permit conditions are legally appropriate depends on the law and the record developed during the permit process. Although site-specific requirements are typically resource intensive because they require development on a site-by-site basis, they can be developed and have commonly been included in hazardous waste site permits.

Therefore, although CAIS may be stored, disposed of, or treated at a federally permitted hazardous waste treatment, disposal, or storage facility, additional requirements may also be imposed because of the specific characteristics of this waste.

Normally, the type of hazardous waste that can be treated at a commercial facility is limited by the operating permit. Even without an explicit limitation in a permit, a prudent treatment, disposal, or storage facility operator may decide to obtain the approval of the permitting authority prior to accepting a unique type of waste. In some cases, the facility operator may seek objective verification from the waste generator that the waste can legally be disposed of without additional requirements and an ironclad indemnification from the generator.

Thus, EPA or a state may impose a site-specific permit condition (e.g., a limit on the concentration of arsenic in wastes that may be incinerated) if there is a legal and factual basis for such a condition in the administrative record (e.g., a site-specific risk assessment demonstrating that exposures to workers or residents beyond the site boundary would be exposed over a lifetime to unacceptable risks from incineration of wastes containing higher concentrations of arsenic). Therefore, the generator (in this case the Army) will have to supply an objective, scientific record as a basis for allowing treatment of the chemicals in CAIS. Most (but not all) of these chemicals are not "typical" commercial hazardous waste streams. The disposal or storage of CAIS according to the standard operating permit and monitoring requirements may or may not be as "safe" as the disposal of other commercial hazardous wastes. As noted in Chapter 4 of this report, the

scientific support for allowing the disposal of CAIS at commercial hazardous waste facilities has simply not been developed and is not well documented.

In the unlikely event that neither federal nor state officials requires a permit modification, local and national environmental groups concerned about the disposal of stockpile and non-stockpile agents are likely to petition EPA and/or the state for a permit modification. As a practical matter, therefore, EPA and/or the state regulatory body are likely to require a site-specific permit modification.

The statutory scheme for the disposal of stockpile chemical agents requires that the Army provide "maximum protection for the environment, the general public, and the personnel who are involved in the destruction of the lethal chemical agents and munitions" (50 U.S.C. § 1521(c)(1)(A)). Although this provision might not apply to CAIS legally, Army guidance documents suggest that it might. There is no clear definition of "maximum protection" or ''maximally safe" provided in statute, regulation, or Army guidance. However, there is a wealth of precedent for interpreting similar terms in other statutes.

Courts give deference to agency decisions that "must be made on the frontiers of science," (i.e., in areas where harm cannot be demonstrated based solely on scientific proof) (50 U.S.C. § 1521(c)(1)(A)). Thus, the U.S. regulatory agencies are generally "not required to support . . . [their] findings with anything approaching scientific certainty" (Indus. Union Dept. v. API). Courts in the United States have generally upheld environmental regulations, even though (1) the method of extrapolating from observed biological effects in animals exposed to high levels to predicted adverse health effects in humans exposed to much lower levels, involves assumptions; and (2) there is a lack of scientific certainty regarding the validity of such assumptions (Indus. Union Dept. v. API, p. 656; NRDC v. EPA, p. 1165). As the court unanimously explained, "there is no particular reason to think that the actual line of the incidence of harm versus degree of exposure is as assumed" (NRDC v. EPA, p. 1165).

Most statutes require a balance of risk, costs, and various other factors. However, if statutes explicitly and unequivocally state that no real risk is allowed (e.g., the now repealed Delaney Clause, which forbade carcinogens at any level from being used as food additives), then zero risk is upheld by the courts.⁵ In another judicial decision, the court stated that, although "Congress did not dictate that the EPA engage in an exhaustive, full scale, cost-benefit analysis" when making decisions pursuant to the Toxic Substances Control Act, it "did require EPA to consider both sides of the regulatory equation," and it rejected the notion that the EPA should pursue the reduction of risk at any cost (Corrosion Proof Fittings v. EPA).

Thus, EPA does not have unlimited discretion, and decision making must include risk management factors, such as costs, depending on the statute. Economic and political factors are explicitly included in the process of selecting the "acceptable" or "safe" risk

level (i.e., risk management). It is generally acknowledged that increasing the margin of safety for low-level risks "can reach a point where, by absorbing resources and energy and impeding innovation and growth, it can do both individuals and society more harm than good . . . . The problem is how to know when to stop . . . [and] how to know when prudence and care become over-reaction or paranoia" (Morgan, 1985, pp. 107, 140).

Risk management criteria have evolved over the last several decades. Historically, most chemicals were originally regulated based on noncarcinogenic effects by reviewing animal studies and applying safety and uncertainty factors. Until the late 1950s, few chemicals were regulated as carcinogens. As public perception grew that zero risk could not be attained, a series of statutes were enacted that required the management, rather than elimination, of those risks. Over time, federal regulators developed the risk assessment process (NRC, 1983, pp. 53-55).

Initially, EPA assumed that any concentration of a chemical found to cause cancer in an animal was capable of increasing the lifetime probability of cancer in humans, and the term safe was reserved for chemical concentrations that would not result in any probability of adverse health effects (NRC, 1983, pp. 57-58). In 1979, in response to the practical problems of setting regulatory levels, federal agencies (including EPA) formally adopted the risk-assessment process as a tool for setting regulatory levels (Interagency Regulatory Liaison Group, 1979; The Regulatory Council, 1979; EPA, 1979, pp. 58642, 58660.).

Throughout the 1970s, zero exposure was assumed to be the only safe level for carcinogens because, theoretically, even one molecule of a carcinogen could cause cancer, and safe was equated with no risk of adverse health impacts (EPA, 1979; EPA, 1980). Some people even argued that every individual had the "inherent right to protection" ⁶ and that zero emissions were the only appropriate basis for setting regulatory standards (BNA, 1988). This draconian interpretation would have required the shutdown of most, if not all, facilities in the utility, steel, mining, synthetic chemical, petroleum, and other industries.⁷ EPA and the courts concluded that Congress could not have intended to eliminate virtually every major industry in the United States (EPA, 1979, pp. 58652, 58658; NRDC v. EPA, p. 1165).

Other regulations issued in the 1970s were based on the extent to which technology could reduce pollution. In the nuclear regulatory field, for example, the lowest achievable levels were used to define radiation safe levels. In other statutes, best available technology was used to define safe levels.

It is now well established in EPA policy and in law, however, that safe is not necessarily the same as risk free, and mere exposure is not sufficient to support regulation unless there is a significant risk (Indus. Union Dept. v. API, p. 642; NRDC v. EPA,

pp. 1164-65). EPA has concluded that a 10^-4 risk level is to be used at Superfund sites,⁸ in national drinking water standards (EPA, 1992, pp. 31797; 31816; 31843),⁹ in the Clean Air Act (EPA, 1990b; NRDC v. EPA), in the underground injection control program (EPA, 1988a, pp. 28118; 28123), and in numerous other EPA and other federal regulatory decisions (EPA, 1988b, p. 28486; Wilson and Crouch, 1987; Travis and Hattemer-Frey, 1988; Travis et al., 1987). As a practical matter, technical feasibility, costs, and other factors regularly result in risk levels higher than 10^-6 being accepted. The "average" level of residual risk considered acceptable by federal agencies in regulatory actions is approximately 10^-5 (Travis and Hattemer-Frey, 1988, p. 875; Travis et al., 1987, p. 419; EPA, 1990b, pp. 8299-8300).

In all of these regulatory decisions, the agencies and courts eventually arrived at interpretations recognizing that the costs of zero risk are astronomical and, as a practical matter, did not provide a biologically meaningful decrease in the level of the risk. Since the 10^-4 risk level is safe, there is arguably no meaningful, incremental reduction in human health below the risk level.

Thus, the Army could interpret maximum protection of public health as 10^-4 risk level. Even though this interpretation is possible, however, nothing compels the interpretation. Obviously, the preferred approach is for Congress to clarify what this term means and then provide adequate funding to implement this level of protection.

No specific regulation or guidance document requires a search for CAIS. CAIS are usually found incidentally during normal construction activities on active or former military bases or during investigations initiated at a base as part of an environmental restoration program, a Base Realignment and Closure Act (BRAC) program, or during cleanup of a Superfund site.

On environmental restoration sites, BRAC bases, Superfund sites, and military bases subject to state investigations, efforts to locate CAIS are likely. Otherwise, CAIS may remain buffed and may be periodically discovered even after the disposal deadlines in the CWC have passed. In fact, at this time, the Army has no active program to search for CAIS. Once CAIS are found, land use dictates the response. CAIS found in a residential area present different risks than CAIS found on an active military base, a BRAC site, or an industrial or commercial site.

Once found, CAIS are considered CWM and are subject to Army, EPA, and state regulations. Army regulations require the disposal of CWM. CAIS are also considered hazardous waste and must be handled according to federal and state hazardous waste regulations. CAIS are not, however, military munitions as defined by the EPA military munitions rule. EPA, a state, or other regulatory body can impose additional health and safety requirements on permitted facilities receiving CAIS for treatment.

EPA distinguishes between wastes left in situ and wastes that have been excavated and moved out of the area of contamination at a Superfund or hazardous waste corrective-action site. No federal, state, or local permits are required for wastes

(including CAIS) stored, disposed of, or treated on a Superfund site, although the substantive requirements of the federal and certain state regulatory requirements must be met. However, the substantive requirements of the federal hazardous waste land disposal restrictions and some other hazardous waste treatment requirements do not apply to waste treated on a Superfund or corrective-action site within what is called a corrective-action management unit (generally, the area of contamination).

Once CAIS are removed from the ground and taken outside the corrective-action management unit, they are considered a hazardous waste and CWM. Therefore, CAIS cannot be stored on site for more than 90 days without a permit. If the CAIS are found on a Superfund site, no federal, state, or local permits are required as long as the CAIS remain on the site, although the substantive requirements of the federal and some state environmental laws must be met, unless the remedial action is temporary or one of the other Superfund waivers applies. The technical hazardous waste requirements applicable for long-term storage must be met if CAIS are stored for the long term, unless one of the waiver provisions applies. As a practical matter, the hazardous waste laws require that CAIS be removed from the site in a relatively short period of time.

EPA hazardous waste regulations apply to the treatment of CAIS, regardless of whether the treatment is on site, at a regional facility, and regardless of whether a commercial facility or Army facility is used. Presently, CAIS can be treated in place using the Rapid Response System (RRS). However, pursuant to the hazardous waste laws, a hazardous waste cannot be treated at the location where it is found without a hazardous waste permit, unless it is a Superfund site. Thus, the RRS must meet federal and state hazardous waste permitting requirements. EPA or a state can also impose additional health and safety requirements governing the treatment in place of CAIS through the permit process. The Army and other regulatory bodies can also impose additional requirements based on the federal statutes governing CWM.

The movement of CAIS off site is subject to the U.S. Department of Transportation (DOT) rules and Army rules for the transport of CWM. DOT has approved a specific type of container for the transport of CAIS that must be used wherever the CAIS are found and sent by the Army, or possibly by a commercial waste transportation company (DOT, 1998). The RRS also complies with DOT requirements (Cushmac, 1998). According to the Army, current regulations require that the Army Technical Escort Unit transport CAIS to any storage or disposal site.

If CAIS are stored off site, the conditions must comply with EPA hazardous waste storage requirements, whether the facility is commercial or at an Army base. In addition,

the Army storage requirements for CWM must be followed. A commercial facility would probably need a permit modification to allow the storage of CAIS. According to the Army, CAIS are currently being stored at Army bases in facilities that meet EPA, state hazardous waste, and Army specifications.

If CAIS are treated off site, the treatment must be in compliance with the federal and state hazardous waste treatment regulations. A permit modification is likely to be required for commercial facilities, ¹⁰ The primary issue for a permit modification is generic (i.e., can CAIS be treated at a permitted hazardous waste treatment facility in a manner that protects human health and the environment).

If a facility does not obtain a permit modification, it faces a legal risk that EPA or the state may take an enforcement action and/or that local citizens may file a citizen action claiming a violation of the permit. Whether public notification prior to accepting CAIS materiel at a commercial facility is required is a complex question. However, failure to notify the public near the commercial facility that the facility is considering accepting CAIS could present significant problems.¹¹

EPA, the state, and other regulatory bodies can impose additional health and safety requirements on permitted facilities receiving CAIS for treatment. The Army's policy is not to treat CAIS at stockpile chemical agent treatment facilities, because of 50 U.S.C. 1512a. Any off-site facility or facilities constructed specifically to treat or store CAIS material must meet all hazardous waste regulatory requirements and Army requirements.

The main difference between the typical treatment of hazardous waste and the treatment of CAIS is in the handling of the CAIS prior to disposal. The most critical issue is the risk of catastrophic failure during unpacking and other handling of the CAIS material. The Army's current procedures seem adequate, but these procedures may not be used at every commercial hazardous waste facility.

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