The U.S. Army is currently in the process of disposing of the nation’s obsolete stockpile of chemical agents and munitions, which are considered to be hazardous waste. Secondary waste materials are being generated from the processes used to destroy this primary waste at five currently operating chemical agent disposal facilities in the continental United States. Management and disposal of the growing volume of secondary waste has become a major consumer of staff time and effort at these facilities.
This study is concerned only with the wastes that are generated as a result of disposal operations at the four baseline incineration system facilities and one other facility that uses neutralization (hydrolysis) technology as the means of agent destruction. The facilities using incineration are located at Anniston, Alabama; Pine Bluff, Arkansas; Umatilla, Oregon; and Tooele, Utah. These facilities dispose of a variety of chemical munitions as well as bulk agent stocks of the nerve agents sarin (GB) and VX and of mustard, a blister agent. The facility using neutralization technology, located at Newport, Indiana, uses caustic hydrolysis to destroy the VX agent stored there in bulk ton containers. A lesson from the closure of the U.S. Army’s first-generation incineration facility, the Johnston Atoll Chemical Agent Disposal System (JACADS), was that the costs and time required for closure were significantly increased because the thousands of tons of secondary waste that had accumulated had to be disposed of. The experience at JACADS clearly showed that it is preferable that secondary wastes should be managed and disposed of concurrently with primary agent disposal operations rather than stored until the end of the agent disposal campaigns.
Secondary wastes may or may not be contaminated with agent residues. Depending on the particular constituents involved and the method of waste generation, these wastes may be classified as hazardous or non-hazardous. Most of the wastes generated during the operation of the disposal process are the same at the various facilities, with some exceptions for the neutralization facility at Newport. Quantities may differ because of the duration of operations and the particular mix of munitions being destroyed. Therefore, many of the challenges concerning waste management and disposal are the same across the program. This study considers all major wastes streams that are generated during agent disposal operations as well as during facility closure. It concentrates on the following major waste streams being generated from the destruction processing of stockpile agent and munitions, including munitions handling:
Spent activated carbon;
Brine solutions or brine salts;
Dunnage, consisting primarily of wooden pallets;
Metal from munitions or ton containers;
Plastics, particularly used demilitarization protective equipment; and
Spent decontamination solutions.
The issues surrounding the effects on closure operations from waste generation and management before and after completion of stockpile disposal operations are also considered.
While the waste streams are essentially the same for all facilities, the way they are managed is not. The chemical agent disposal facilities are all regulated under the Resource Conservation and Recovery Act (RCRA) by the respective state regulatory authorities, and each facility operates under a RCRA permit. These permits were initially negotiated prior to facility construction, when waste types but not quantities were generally known. The permits were therefore modified to a greater or lesser extent as disposal operations proceeded, depending on the local situation. Thus, local regulations and stakeholder concerns play a role in what any facility can do. In three states, for example, the wastes generated from the operation of the chemical agent disposal facility are “listed hazardous wastes,” while in the other two states they are not. This has a significant influence on how the wastes can be managed. Listed wastes and wastes derived from listed wastes must be treated as hazardous even if they do not exhibit hazardous characteristics, with the exception that they may be delisted.
Permit conditions will also affect the disposition of waste. For example, in Oregon all waste, with some minor exceptions, must be treated on-site. This significantly inhibits the options for disposal of the wastes off-site. Treatment on-site is limited by the capacity of the metal parts furnace (MPF) and its availability when it is not processing the munitions. Permits at the other locations are not as restrictive as in Oregon, which requires on-site treatment of secondary waste. The detailed differences in operations are discussed in Chapter 3 of the report.
The committee was also asked to evaluate the trial burn practices at the incineration-based facilities and compare them with similar practices in industry. Each Chemical Materials Agency (CMA) incineration facility has several types of incinerators and each has been required, by permit, to carry out a surrogate burn on all of its furnaces after start-up and before feeding any agent. A surrogate trial burn is required to demonstrate the ability of the unit to achieve a 99.9999 percent (“six nines”) destruction and removal efficiency and unit operability. They have then been required to carry out a trial burn with each agent. After the trial burn, the feed rates are reduced to 50 percent until the trial burn data have been submitted, and to 75 percent until the data have been accepted. This is a lengthy process.
While industrial practice requires a trial burn and a facility may not operate until the data are accepted, industrial facilities obtain approval to process many different waste streams based on a single trial burn. In special situations, particularly with toxic materials such as polychlorinated biphenyls, both a surrogate burn and a trial burn would be required. RCRA regulations offer the option of allowing the use of data from another facility, under certain conditions, in lieu of a trial burn. However, industry has used this mechanism at only a few sites with similar units. It has been used twice by the CMA for the Tooele, Utah, disposal facility. The CMA should pursue this mechanism with the respective regulatory authorities. The committee believes that chemical agent disposal facilities are treated similarly to industrial facilities with respect to the conduct of trial burns.
The committee’s study of site-specific secondary waste practices and requirements focused on the six major waste streams produced by the chemical agent disposal operations. Of the six, brine and brine salts are treated and disposed of off-site during operations at permitted treatment, storage, and disposal facilities. At the Umatilla site, brine solutions are thermally treated to produce a solid salt, which is then shipped off-site to a hazardous waste landfill. However, brine solution may be disposed of off-site if thermal treatment to produce a brine salt impedes the main mission of the agent disposal operation. Brine and brine salts must meet the established waste control limit for off-site disposal—that is, the agent concentration must be below the permit limit for materials containing agent.
Of the five remaining major waste streams, spent activated carbon is being stored at each facility for later disposal. Munitions bodies and other scrap metal are sent to off-site smelters after being thermally treated to a clean condition in the MPF at the four incineration-based facilities. Because on-site secondary waste processing capacity is limited, demilitarization protective ensemble suits are shipped off-site or stored until they can be treated on-site in the MPF when it has an opening in its schedule or at the end of agent destruction operations.
Wood dunnage is separated into that which has not been exposed to agent and that which may have been exposed. This segregation is based on generator knowledge and vapor monitoring. Unexposed dunnage is
typically disposed of as ordinary nonhazardous waste. Agent-contaminated dunnage is thermally treated in the MPF as scheduled operations allow or is stored until the end of agent disposal operations, due to limited on-site secondary waste processing capacity.
At the Newport Chemical Agent Disposal Facility (NECDF), instead of the brine solution and furnace slag found at incineration facilities, an aqueous liquid waste stream is generated as a result of the neutralization (chemical breakdown) of the chemical agent VX. Several plans for treating and disposing of Newport hydrolysate have been considered. Most recently, this hydrolysate waste from the first-stage VX neutralization was to be disposed of off-site by chemical and biological treatment in a commercial treatment, storage, and disposal facility (TSDF). Approximately 1.5 million gallons of VX hydrolysate is expected to be generated at NECDF. The disposition of this material has been in dispute and is still under study by the Army.1 The nature of the final waste stream resulting from a second processing step for the VX hydrolysate has consequently not yet been defined. Many of the other wastes from NECDF are similar to those found at the baseline incineration sites.
The committee found that the regulatory requirements with respect to waste characterization and disposal were similar for industrial facilities and the Army’s chemical agent disposal facilities. Minor exceptions are discussed in the body of the report. The main result of the analysis by the committee, as detailed in the findings and recommendations, is that it is both technically feasible and advantageous to dispose of as much waste as possible off-site at approved TSDFs during operations. Also, the mechanism provided for in the Resource Conservation and Recovery Act, which allows data from earlier trial burns conducted in similar incinerators to be used in lieu of conducting an additional trial burn for another disposal facility incinerator, should be utilized to the fullest extent possible. All findings and recommendations are listed in Chapter 5. The most significant appear below.
FINDINGS AND RECOMMENDATIONS
Finding 2-1. An examination of the situation concerning trial burn requirements for incinerators at chemical agent disposal facilities has led to several observations:
Surrogate trial burns demonstrate that incinerators at chemical agent disposal facilities can operate safely. The requirement to perform surrogate trial burns at these facilities is consistent with the initial start-up procedures followed at commercial hazardous waste incineration facilities.
In the earlier phases of the Army’s Chemical Stockpile Disposal Program, an agent trial burn conducted for each incinerator with each agent to be processed was an appropriate way for disposal facility staff and state regulatory staff to gain operational experience and confidence in the performance of the incinerators.
As the Chemical Stockpile Disposal Program has matured, there has been only limited use of the data-in-lieu-of regulatory mechanism provided for in the Resource Conservation and Recovery Act. This provision, if applied more extensively to chemical agent disposal facilities, could allow data from other similar incinerators at chemical agent disposal facilities to be used in lieu of conducting additional agent trial burns.
Recommendation 2-1. The Chemical Materials Agency should vigorously pursue the application of the Resource Conservation and Recovery Act provision for using trial burn data from other similar chemical agent disposal facility incinerators in lieu of conducting trial burns for additional agents. This is a reasonable way to proceed now that (1) at least one agent trial burn has occurred for each type of agent in each type of incinerator at all the chemical agent disposal facilities and (2) a surrogate trial burn and an initial agent trial burn have occurred for each incinerator at all sites.
Finding 2-2. The time required to obtain state regulatory approval to proceed to a full feed rate following submission of agent trial burn data for incinerators at chemical agent disposal facilities can be lengthy. This is a consequence of the volume and complexity of the documents filed, as well as limited state regulatory agency resources to review and analyze them.
Recommendation 2-2. The Chemical Materials Agency should seek to provide funding to state authorities for third-party or other support to facilitate the analysis and disposition of trial burn data. This would shorten the time needed to obtain approval for incinerators at chemical agent disposal facilities and allow them to proceed more rapidly to a full processing rate.
Finding 2-5. The committee’s examination of how transportation risk assessments for agent-contaminated waste materials are conducted at chemical agent disposal facilities indicated that widely differing models and parameters have been used. A specific problem identified by the committee is that the methodology used for general ton-mile data in transportation risk assessments to achieve a Class 6 ton-mile value is not consistent.
Recommendation 2-5. The Chemical Materials Agency should establish consistent and detailed criteria for conducting whatever transportation risk assessments are required to ensure accuracy and uniformity in the expression of results.
Finding 3-1. In the absence of better techniques for measuring agent concentrations on certain heterogeneous, porous, and permeable materials, indirect measurements leading to conservative classifications of waste materials are being used at chemical agent disposal facilities.
Recommendation 3-1. The Chemical Materials Agency should develop improved analytical techniques for heterogeneous, porous, and permeable materials. Better analytical techniques could enable more exact quantification of agent contamination to meet off-site shipping criteria and help reduce waste remaining on-site at the end of munitions destruction operations.
Finding 3-3. The availability and capacity of equipment for the concurrent treatment of secondary waste during agent disposal operations or changeovers at chemical agent destruction facilities is severely limited in comparison with the capacity available at off-site commercial treatment facilities that could process the waste.
Recommendation 3-3. The committee encourages the CMA to continue the pursuit of off-site shipment and disposal of >1 STL secondary waste. The committee believes this can be done safely in a ramp-up fashion, based on the use of double bags and containerized packing, truck loading restrictions, designated handling and shipping routes, air monitoring at the receiving TSDF, and restrictions on the disposal technique. Appropriate details, including permit modifications, must be worked out in conjunction with the local regulatory agencies and local stakeholders for the practice to be allowed.
Finding 3-4. Contaminated activated carbon from the treatment of several different waste streams is a major waste disposal problem at all chemical agent disposal facility sites. The micronization pretreatment of activated carbon in preparing it to be destroyed by on-site incineration has been shown to be a highly problematic process option.
Recommendation 3-4. The Chemical Materials Agency should select an alternative to on-site micronization followed by incineration for decontamination and/or destruction, and ultimate disposal of contaminated activated carbon. Off-site decontamination, and/or destruction and disposal of contaminated activated carbon should be pursued whenever possible.
Finding 3-5. Some of the mustard agent to be processed at the Tooele Chemical Agent Disposal Facility and the Umatilla Chemical Agent Disposal Facility is mercury-contaminated and will result in some of the activated carbon from the pollution abatement system also being contaminated with mercury. Special treatment may be required or additional challenges may be faced in disposing of this carbon.
Recommendation 3-5. The Chemical Materials Agency should evaluate and select appropriate methods for the treatment and disposal of mercury-contaminated carbon. Mercury-contaminated carbon should not be intermingled with other contaminated carbons during storage.
Finding 3-8. The waste management practices for demilitarization protective ensemble suits and other plastics are limited by the on-site capacity for treatment and, at some sites, by the regulatory restrictions for off-site disposal.
Recommendation 3-8. The Chemical Materials Agency should actively pursue off-site shipment and disposal of waste plastic and personal protective equipment such as
demilitarization protective ensemble suits from all sites based on adherence to and enforcement of packing, shipping, monitoring, and treatment restrictions.
Finding 3-9. As of January 2007, over 500,000 gallons of VX hydrolysate generated by the neutralization destruction of bulk nerve agent VX at the Newport Chemical Agent Disposal Facility was being stored in more than 140 intermodal storage containers. It is anticipated that 1.5 million gallons of VX hydrolysate will eventually be generated. Studies by outside government agencies and technical organizations have found that safe, environmentally sound, off-site disposal of VX hydrolysate (such as that proposed by DuPont) is technically feasible.
Recommendation 3-9. The Chemical Materials Agency should evaluate and select an appropriate method to dispose of the VX hydrolysate currently being stored at the Newport, Indiana, site, with preference for off-site disposal.
Finding 3-10. Each chemical agent disposal facility in this study has established open and effective communication channels and has regular dialogue with its Citizens Advisory Commission and other local stakeholders. The input of these stakeholders is also sought by regulatory officials and is an important factor in negotiating permit modifications concerning secondary waste disposal practices.
Recommendation 3-10. The Chemical Materials Agency should continue its support for and emphasis on local stakeholder input and involvement as mission-critical elements when acceptable secondary waste disposal practices are being defined and regulatory permit requirements are negotiated.
Finding 4-1. Closure planning and the time to achieve closure for chemical agent disposal facilities are both very dependent on the extent of waste treatment and disposal that occurs during agent disposal operations—that is, on the degree of concurrent waste minimization that takes place. However, there is only limited treatment capacity for secondary waste during agent disposal operations and changeovers at chemical agent disposal facilities.
Recommendation 4-1. The Chemical Materials Agency should use off-site disposal concurrent with ongoing agent disposal operations wherever possible, practical, and environmentally sound for all secondary and closure wastes generated during operations.
Finding 4-2. An analytical methodology for establishing agent contamination levels in porous wastes generated during closure, such as concrete scrabble, is not available.
Recommendation 4-2. The Chemical Materials Agency should develop appropriate analytical methods for establishing agent levels in porous materials and have them certified at the earliest possible time as a means of minimizing closure costs.