5
Update of General Findings and Recommendations
Chapter 11 in Review and Evaluation of Alternative Technologies for Demilitarization of Assembled Chemical Weapons included 16 general findings and 7 general recommendations (NRC, 1999). Those findings and recommendations are quoted below and are followed by the current committee’s evaluation of how the Demo II tests affect the status of the technologies. The findings in the ACW I supplemental report, Evaluation of Demonstration Test Results of Alternative Technologies for Demilitarization of Assembled Chemical Weapons: A Supplemental Review (NRC, 2000), pertained to the three technologies tested during Demo I and are not relevant to the Demo II technologies.
REVIEW OF EARLIER FINDINGS AND RECOMMENDATIONS
General Finding 1. The chemistries of all four of the primary technologies, (hydrolysis, SILVER II™, plasma arc, and SET™) as proposed, can decompose the chemical agents with destruction efficiencies of 99.9999 percent. However, each technology package raises other technical issues that must be resolved. One of the crucial issues is the identity and disposition of by-products.
The Army has produced large quantities of hydrolysate from GB, VX, and HD in which no agent can be detected, thereby confirming that DREs of 99.9999 percent have been achieved. The Demo II testing of the AEA SILVER II™ process has also been shown to achieve DREs of 99.9999 percent for VX, HD, and GB. The Teledyne-Commodore SET™ process was discontinued before progressing to tests with live agent. Complete destruction of agents by the SET™ technology has not been confirmed.
General Finding 2. The technology base for the hydrolysis of energetic materials is not as mature as it is for chemical agents. Chemical methods of destroying energetics have only been considered recently. Therefore, there has been relatively little experience with the alkaline decomposition of ACWA-specific energetic materials (compared to experience with chemical agents). The following significant issues should be resolved to reduce uncertainties about the effectiveness and safety of using hydrolysis operations for destroying energetic materials:
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the particle size reduction of energetics that must be achieved for proper operation
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the solubility of energetics in specific alkaline solutions
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process design of the unit operation and the identification of processing parameters (such as the degree of agitation and reactor residence time) necessary for complete hydrolysis
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the characterization of actual products and by-products of hydrolysis as a function of the extent of reaction
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the selection of chemical sensors and process control strategies to ensure that the unit operation following hydrolysis can accept the products of hydrolysis
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development of a preventative maintenance program that minimizes the possibility of incidents during the cleanup of accumulated precipitates
General Finding 3. The conditions under which aromatic nitro compounds, such as trinitrotoluene (TNT) or picric acid, will emulsify in the aqueous phase and not be completely hydrolyzed are not well understood. Therefore, this type of material could be present in the output stream from an energetic hydrolysis step.
General Finding 4. The products of hydrolysis of some energetic materials have not been characterized well enough to support simultaneous hydrolysis of different kinds of energetic materials in the same batch reactor.
General Recommendation 5. Whatever unit operation immediately follows the hydrolysis of energetic materials should be designed to accept emulsified aromatic nitro compounds, such as TNT or picric acid, as contaminants in the aqueous feed stream. (See General Finding 3.)
General Recommendation 6. Simultaneous processing of different types of energetic materials should not be performed until there is substantial evidence that the intermedi-
ates formed from the hydrolysis of aromatic nitro compounds will not combine with M28 propellant additives or ordnance fuze components to form extremely sensitive explosives, such as lead picrate. (See General Finding 4.)
The PMACWA has established a technology base program to address the NRC’s concerns about the hydrolysis of energetic materials. This program will be reviewed and evaluated in the EDS reports that address Tasks 2 and 3 in the ACW II committee’s statement of task. However, as discussed earlier in Chapters 2 and 4, the committee believes that the destruction of energetics by both the SILVER II™ and the SET™ processes, which do not involve hydrolysis, remains immature. This finding is illustrated by the unexpected, and as yet unexplained, formation of insoluble intermediates in the anolyte vessel in the SILVER II™ processing of tetrytol.
General Finding 5. The primary chemical decomposition process in all of the technology packages produces environmentally unacceptable reaction products. Therefore, all of the packages are complicated processes that include subsequent treatment step(s) to modify these products.
General Finding 6. The waste streams of all of the ACWA technology packages could contain very small amounts of hazardous substances (besides any residual chemical agent). These substances were not fully characterized at the time of this report; therefore, all waste streams must be characterized to ensure that human health and the environment are protected. If more than one phase (gas, liquid, or solid) is present in a waste stream, each phase should be characterized separately.
Although effluent streams were extensively characterized during Demo II, the tests were of short duration and took place in undersized reactors. Consequently, the effluent streams were not characterized under actual or optimized conditions and may not be representative of the effluents that would be produced in full-scale operation.
General Finding 10. Testing, verification, and integration beyond the 1999 demonstration phase will be necessary because the scale-up of a process can present many unexpected challenges, and the ACWA demonstrations were limited in nature.
The PMACWA is planning an EDS testing program (EDS II) for both the Foster Wheeler/Eco Logic/Kvaerner and the AEA technology packages. The EDS II program, which has objectives similar to those of EDS I, will produce engineering design packages and further testing of the two technologies. As a result of the problems and delays during the initial testing and investigation of the Teledyne-Commodore technology package, the PMACWA has dropped SET™ from consideration.
The committee considers the Demo II tests as proof-ofconcept tests of the demonstrated unit operations. The critical step of integrating them has not yet been addressed by the technology providers. Therefore, the following general findings and recommendations, all related to integration, were not affected by the Demo II tests.
General Finding 7. None of the proposed technology packages complies completely with the hold-test-release concept for all gaseous effluents (both process and ventilation effluents).
General Finding 8. Hold-test-release of gaseous effluents may not ensure against a release of agent or other hazardous material to the atmosphere. No evidence shows that hold-test-release provides a higher level of safety than current continuous monitoring methods for gaseous streams with low levels of contamination. Furthermore, none of the technologies provides for hold-test-release of effluents from ventilation systems that handle large volumes of gases from contaminated process areas.
General Finding 9. Solid salts will be hazardous waste, either because they are derived from hazardous waste or because they leach heavy metals above the levels allowed by the Resource Conservation and Recovery Act Toxicity Characteristic Leaching Procedure. Stabilization—mixing waste with a reagent or reagents to reduce the leachability of heavy metals—will probably be required before the salts can be sent to a landfill. The potentially high chloride and nitrate content of these salts will make the waste difficult to stabilize, and treatability studies will be necessary to determine a proper stabilization formula.
General Finding 11. Although a comprehensive quantitative risk assessment (QRA), health risk assessment (HRA), and ecological risk assessment (similar to assessments performed for the baseline process) cannot be completed at this stage of process development, these assessments will have to be per-formed and refined as process development continues.
General Finding 12. The “optimum” system for a particular chemical weapons storage depot might include a combination of unit operations from the technology packages considered in this report.
General Finding 13. Some of the ACWA technology providers propose that some effluent streams be used commercially. New or modified regulations may have to be developed to determine if these effluent streams can be recovered or reused.
General Finding 14. An extraordinary commitment of resources will be necessary to complete the destruction of the assembled chemical weapons stockpile in time to meet the current deadline using any of the ACWA technology packages. This would demand a concerted national effort. It is unlikely that any of the technology packages could meet this deadline.
General Finding 15. The Dialogue process for identifying an alternative technology is likely to reduce the level of public opposition to that technology. The committee believes that the Dialogue has been and continues to be a positive force for public acceptance of alternatives to incineration.
Although the Dialogue process requires a significant commitment of time and resources, it has been a critical component of the ACWA program to date.
General Finding 16. Although the committee did not have access to scientific data on the attributes of a technology that would be most acceptable to the public, input from members of the active publics and previous research indicate that technologies with the following characteristics are likely to stimulate less public opposition:
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minimal emissions, particularly gaseous
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continuous monitoring of effluents to verify that the process is operating as designed (process assurance measurement)
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provisions for representatives of the local community to observe and participate in the process assurance measurement
General Recommendation 1. If a decision is made to move forward with any of the ACWA technology packages, substantial additional testing, verification, and integration should be performed prior to full-scale implementation (see General Finding 10).
General Recommendation 2. The sampling and analysis programs at each phase of development should be carefully reviewed to ensure that the characterization of trace components is as comprehensive as possible to avoid surprises in the implementation of the selected technology (see General Finding 6).
General Recommendation 3. If a decision is made to move forward with any of these technology packages, health and safety evaluations should progress from qualitative assessments to more quantitative assessments as the process design matures. Quantitative (QRA), health (HRA), and ecological risk assessments should be conducted as soon as is practical. Early initiation of these assessments will allow findings to be implemented with minimal cost and schedule impact. (See General Finding 11.)
General Recommendation 4. Any of these technology packages, or any component of these technology packages, should be selected on a site-specific basis. (See General Finding 12.)
General Recommendation 7. The Department of Defense should continue to support the Dialogue throughout the current ACWA program and should seriously consider the participation of the Dialogue in follow-on programs.
SUPPLEMENTAL GENERAL FINDINGS
In the statement of task for this report, the committee was asked to determine if any of the technology packages chosen for demonstrations “have reached a technology readiness level sufficient to proceed with implementation of a pilot-scale.” The ACW II committee’s evaluations of the maturity of each unit operation are described in this report. Table 5–1 summarizes the committee’s assessments. However, the AEA, Eco Logic, and General Atomics technology packages were chosen by the PMACWA to undergo engineering design studies for the destruction of the assembled chemical weapons at the Blue Grass Army depot. This decision was made by the PMACWA prior to the issuance of this NRC report. In view of the fact that testing in these areas is ongoing, the committee decided to cut off its fact-finding efforts for input to this report as of March 30, 2001. This cutoff was necessary in order to give the sponsor the information it needed in a timely fashion.
General Finding DII 1. The demonstration tests were not operated long enough to show reliability in long-term operation. The PMACWA’s Demo II tests were required to be of the same duration as the Demo I tests. The technology providers had neither the time nor the resources for extensive systemization (preoperational testing) in Demo II. Consequently, these tests were simply proof-of-concept demonstrations that indicate whether or not a particular unit operation (with more development) might be applicable to the disposal of assembled chemical munitions.
General Finding DII 2. The AEA technology package is a very complex, immature chemical processing system. Several new unit operations required to address problems revealed in the Demo II tests will significantly increase the complexity of an integrated processing system and extend the time required for its development.
General Finding DII 3. The demonstrated components of the FW/EL/K technology package are ready to progress to the EDS phase. However, certain key units were not tested (or the results were inconclusive). Additional testing will be needed to verify the ability of the transpiring-wall technology to minimize corrosion; the testing should be carried out in parallel with development of an engineering design.
General Finding DII 4. Because of fire and safety problems, the basic process for the Teledyne-Commodore technology was not tested in Demo II. The Army decided against going forward because the Demo II goals could not be met in time. As a result, the committee had no technical basis on which to evaluate the process any further.
General Finding DII 5. As was true for Demo I, none of the unit operations tested in Demo II has been integrated into a complete system. The lack of integration is a major concern and a significant obstacle to full-scale implementation.
SUPPLEMENTAL GENERAL RECOMMENDATIONS
General Recommendation DII 1. Further development of the Teledyne-Commodore technology package for the destruction of assembled chemical weapons should not be pursued under the ACWA program.
TABLE 5–1 Summary Evaluation of the Maturity of Demo II Unit Operations and Processes
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Hydrolysates |
Agent Munitions |
|
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Technology Provider/Unit Operation or Process |
VX/GB |
HD |
Energetics |
VX/GB |
HD |
Energetics |
Other |
AEA |
|||||||
SILVER II™a |
|
C |
C |
C |
|
||
Solid/liquid waste treatment |
|
C |
C |
C |
|
||
Gaseous waste treatment |
|
D |
D |
D |
|
||
Foster Wheeler/Eco Logic/Kvaerner |
|||||||
TW-SCWO |
B |
B |
C |
|
|||
GPCR™ |
|
B |
B |
B |
|||
Teledyne-Commodore |
|||||||
Ammonia fluid jet cutting and washout system |
|
D |
D |
E |
|
||
SET™ |
|
D |
D |
D |
Cb |
||
Persulfate oxidation (agent) |
|
D |
D |
D |
|
||
Peroxide oxidation (energetics) |
|
D |
D |
D |
|
||
Metals parts and dunnage shredding |
|
||||||
NOTE: Environmental and safety issues were considered in assigning maturity categorizations. Schedule and cost issues were not considered. The letter designations are defined as follows (a blank space indicates that categorization was not applicable for that material): A, demonstration provides sufficient information to justify moving forward to full-scale design with reasonable probability of success; B, demonstration provides sufficient information to justify moving forward to the pilot stage with reasonable probability of success; C, demonstration indicates that unit operation or process requires additional refinement and additional demonstration before moving forward to pilot stage; D, not demonstrated, and more R&D is required; and E, demonstrated unit operation or process is inappropriate for treatment. aIncludes integrated gas polishing system to support demonstration. bDunnage. cMetal parts. |
General Recommendation DII 2. Before the AEA technology proceeds to the EDS phase, extensive testing should be performed on the SILVER II™ process, including all the new unit operations that are being proposed to address the shortcomings identified in Demo II results.
General Recommendation DII 3. For the FW/EL/K technology package, additional testing should be performed in the EDS phase to complete GPCR™ off-gas characterization and demonstrate long-term operation of the modified TW-SWCO unit.