3

Technologies for Rocket Motor Disposal

RECYCLING OPTIONS

The first choice for any demilitarization or disposal program should be to recover materials. The committee does not believe that this option is practical in the case of the M28 propellant, however, because it is old and degraded. There are few applications for aging rocket motor assets in general, and incorporating nitrate ester rocket motor propellants that are specifically derived from chemical weapons, such as the M28 propellant, into new applications is unlikely.

Attempts to recycle nitrocellulose and nitroglycerin from double-base1 propellants have not yielded acceptable products. Trace contamination by constituents of a degraded propellant in a recovered material can have a serious adverse effect on the cure times and safe storage life of any propellant made from recovered materials. The nitrocellulose in the M28 propellant is degraded to the point where it is unlikely that any current program of record for manufacturing new rocket propellant would be willing to incorporate it. Furthermore, program-office requalification costs are substantial when alternative sources of fully characterized composition are introduced into a program’s inventory. This is an issue especially when a propellant ages and produces chemical species that catalytically degrade the propellant even when they are present only at trace concentrations. Although it might be possible to extract and purify the nitroglycerin for recycling, it would entail much work to determine whether this were worth while. The committee does not believe that it would be a practical or worthwhile exercise. Investigations into conversion of these energetic materials to other products, such as fertilizer, have also met with little success. The fact that the M28 propellant contains lead, which cannot be removed without destroying the propellant matrix by chemical or thermal means, complicates any effort to recycle the propellant into fertilizer and further reduces the practicality of recycling in general.

Finding 3-1. There are no practical, useful, or cost-effective means of recycling energetic materials from the M28 propellant.

Metal components of the separated rocket motor2 can be recovered for recycling after they have been mutilated to preclude restoration for further use in a rocket motor (DoD, 2011). In addition, metal scrap must be certified as safe for public release and

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1The term double-base connotes that there are two active constituents in the propellant. In the case of the M28 propellant, they are nitrocellulose and nitroglycerin.

2See Appendix A for how the committee defines separated rocket motor.



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3 Technologies for Rocket Motor Disposal RECYCLING OPTIONS The first choice for any demilitarization or disposal program should be to recover materials. The committee does not believe that this option is practical in the case of the M28 propellant, however, because it is old and degraded. There are few applications for aging rocket motor assets in general, and incorporating nitrate ester rocket motor propellants that are specifically derived from chemical weapons, such as the M28 propellant, into new applications is unlikely. Attempts to recycle nitrocellulose and nitroglycerin from double-base1 propellants have not yielded acceptable products. Trace contamination by constituents of a degraded propellant in a recovered material can have a serious adverse effect on the cure times and safe storage life of any propellant made from recovered materials. The nitrocellulose in the M28 propellant is degraded to the point where it is unlikely that any current program of record for manufacturing new rocket propellant would be willing to incorporate it. Furthermore, program-office requalification costs are substantial when alternative sources of fully characterized composition are introduced into a program's inventory. This is an issue especially when a propellant ages and produces chemical species that catalytically degrade the propellant even when they are present only at trace concentrations. Although it might be possible to extract and purify the nitroglycerin for recycling, it would entail much work to determine whether this were worth while. The committee does not believe that it would be a practical or worthwhile exercise. Investigations into conversion of these energetic materials to other products, such as fertilizer, have also met with little success. The fact that the M28 propellant contains lead, which cannot be removed without destroying the propellant matrix by chemical or thermal means, complicates any effort to recycle the propellant into fertilizer and further reduces the practicality of recycling in general. Finding 3-1. There are no practical, useful, or cost-effective means of recycling energetic materials from the M28 propellant. Metal components of the separated rocket motor2 can be recovered for recycling after they have been mutilated to preclude restoration for further use in a rocket motor (DoD, 2011). In addition, metal scrap must be certified as safe for public release and 1 The term double-base connotes that there are two active constituents in the propellant. In the case of the M28 propellant, they are nitrocellulose and nitroglycerin. 2 See Appendix A for how the committee defines separated rocket motor. 21

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recycling. The Department of Defense (DoD) has instituted a policy for the identification of munitions and munitions scrap that are free of explosive safety hazards (DoD, 2008). The defined process includes specific training, storage, handling, inspection, and certification requirements for all materials potentially presenting an explosive hazard (MPPEH)--that is, any material that has come into contact with an energetic material-- before their release from DoD control. The policy applies to any scrap metal recovered from the separated M55 rocket motors. If the M28 propellant is treated while inside the steel motor case the, remaining metal parts will be contaminated with lead and lead dust. Separation of the propellant, igniter, and other energetic components of the rocket motor from the case, fins, and electronics would simplify the recovery of the scrap metal from these components. However, the recovered metal may still have to be thermally or chemically treated to ensure that energetic residues are destroyed before the materials can be released to a recycler. Finding 3-2. It is feasible to recycle the metal components of the separated rocket motors. Finding 3-3. Depending on the destruction technology used, metal components may be contaminated with lead and lead dust. Recommendation 3-1. The Blue Grass Chemical Agent-Destruction Pilot Plant program staff should inform the recipient of materials for recycling of the potential for the presence of lead or lead dust on recovered materials. OVERVIEW OF DISPOSAL TECHNOLOGIES A wide variety of technologies have been proposed for the demilitarization and disposal of conventional solid rocket motors. The technologies can be divided into thermal and chemical. Thermal technologies for separated rocket motor demilitarization and disposal include open detonation, buried detonation, contained detonation, open burn, open static firing, contained combustion, contained static firing, confined combustion, and incineration. Chemical technologies include base hydrolysis, supercritical water oxidation, and the use of humic acid. The chemical technologies typically require pretreatment in which the propellant is broken into a manageable form (e.g., a solution, powder, or slurry). That process increases the handling of energetic materials and the attendant risks. Thermal treatment usually requires less handling, but precautions must be taken to prevent unplanned detonation or propulsive ejection of the rocket motors. Technologies discussed here are summarized in Table 3-1. The committee envisions that the separated rocket motors would be removed from the shipping and firing tubes before disposal of the separated rocket motors, partly because the shipping and firing tubes contain polychlorinated biphenyls; this is discussed in more depth in Chapter 5. Among the criteria that will need to be considered in selecting a disposal technology for use with the separated rocket motors is the TNT equivalence of the roughly 20 lb of M28 propellant in each motor. 22

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THERMAL TECHNOLOGIES For purposes of the discussion in this report, thermal technologies are organized into two subgroups: open and contained. In open technologies, emissions are not contained or treated before release into the environment. In contained technologies, emissions are contained and treated before release into the environment. A particular subgroup of contained thermal technologies, explosive destruction technologies (EDTs), will also be discussed. If an open technology were used, the emissions from separated rocket motor disposal would need to be within the allowed limits provided in the Air Pathway Assessment section of the Resource Conservation and Recovery Act (RCRA) Subpart X permit for the facility using the technology. In the case of a contained technology, gases and particulate material would be captured and treated with the unit's pollution abatement equipment. The contained technologies would need to be permitted through RCRA Subpart X and would have to meet release limits agreed on with the Kentucky Department for Environmental Protection. Open Thermal Technologies Open Detonation Open detonation involves placing whole or broken-down rocket motors in a pile with a booster explosive. Detonation of the pile initiates a chemical reaction that converts organic energetic materials to carbon dioxide, nitrogen, and water. Emissions from the process do not undergo further treatment and are released into the local environment. They can include metals in the energetic material (such as lead in the M28 rocket propellant), traces of unreacted energetics, materials in the rocket motor cases released and ejected by the detonation, and entrained soil from the detonation site. Noise issues and weather often limit the conditions under which these detonation events can be conducted. Open detonation has several advantages. Handling of energetic items is minimized, and this reduces the risk of unexpected initiation and harm to personnel or facilities. Secondary waste streams are limited to unreacted materials, mostly metal components from the detonated solid rocket motors, such as the case and the fins. Data in emissions databases are sufficient to allow an estimation of total emissions from the process (Erickson et al., 2005; EPA, 2009). Efforts are under way to improve the databases (Kim, 2010; Wright et al., 2010). This technology also has many disadvantages. Emissions are not further treated before release into the environment. In particular, there is a potential for releases of respirable particles from metal components of the energetic formulation, such as the lead in the rocket propellant, or from the soil. Noise issues often cause concerns for facility neighbors and result in regulatory limitations on when the treatment can occur. Propellants like that in the motors of M55 rockets can be difficult to detonate completely, and incomplete detonation occasionally results in distribution of unreacted energetics 23

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over a large area. Other unreacted materials, such as rocket motor cases and liners, can also be distributed over a large area. Most permits require regular cleanup of this material. The release of scrap metal from the open detonation process requires prior screening as MPPEH. Open detonation is a mature technology that is commonly used for munitions demilitarization and emergency ordnance destruction. Throughput from this process will be a function of limits placed on a facility's RCRA Subpart X permit. Buried Detonation Buried detonation is a variant of open detonation in which the pile is covered with 48 ft of soil to suppress detonation noise. The soil also increases safety by minimizing blast and collateral damage that might be caused by metal fragmentation. This technology has the advantage of minimization of the handling of the items being treated. However, it also has disadvantages. Like emissions from open detonation, emissions from buried detonation are not treated further before release into the environment. Because the soil quenches afterburning reactions, buried detonation releases larger quantities of products of incomplete combustion (such as soot and hydrocarbons) than are produced in open detonation. Little work has been done to quantify this phenomenon, but tests are under way to collect pertinent data (Kim, 2010; Wright et al., 2010). The potential exists for environmental releases of metals and organic substances from both the soil and the waste ordnance. Buried detonation is a mature technology that is commonly used for munitions demilitarization. Throughput is constrained by permit treatment limits and the time necessary to prepare the site and bury the ordnance. Open Burning Open burning of rocket motors involves removal of the propellant grain from the case and ignition of the propellant in an open burning pan. As in open detonation, energetic components are largely converted to nitrogen, carbon dioxide, and water. Some facilities use an additional fuel (such as jet fuel) to initiate and support combustion of propellants that are difficult to ignite. Others conduct open burning of whole rocket motors by cracking the motor case open with a shaped charge that also initiates propellant combustion. Gaseous and particulate emissions from the burning propellant are not treated further and are released into the local atmosphere. The combustion occurs at atmospheric pressure. Residual ash requires evaluation as a potential hazardous waste. An advantage of open burning is that components of the rocket are removed before treatment and are available for recycling. Data on open-burning emissions are sufficient to permit an estimation of total emissions from the process (Erickson et al., 2005; EPA, 2009), and efforts are under way to improve the quality of the emissions databases (Kim, 2010). Open burning has several disadvantages in common with open detonation. Emissions do not undergo further treatment before release into the environment. Heavy- metal components of the propellant (such as lead in M28 propellant) are released to the 24

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atmosphere as respirable particles. Most propellants are designed to burn efficiently at high pressures. Burning them at ambient atmospheric pressure results in emissions that contain more products of incomplete combustion (such as soot and hydrocarbons) than would be the case if they were burned as designed. Open burning of rocket motors requires the removal of the propellant from the case to prevent propulsive events, and this increases the handling of the items being disposed of. Finally, ash from the process is probably laden with heavy metals from the propellant formulation and must be tested to determine whether it must be handled as a hazardous waste. This is a mature technology that is commonly used for munitions demilitarization. The Blue Grass Army Depot (BGAD) is operating an open-burning facility under interim permit status. The BGAD facility can treat up to 6,000 lb of energetic material in each treatment event. That would theoretically permit a throughput of up to 300 separated M55 rocket motors per treatment event. The presence of lead in the propellant could lower the throughput because of permit limits on lead releases. Open Static Firing Open static firing of rocket motors involves strapping down of the motor and initiating it in its design mode. This is done in the open, so gaseous and particulate emissions are released into the environment without further treatment. The process minimizes handling and simplifies recovery of components of the rocket motor. Catastrophic failure of aged rocket motors is rare, but not unheard of. The technology has several advantages. As mentioned above, handling is minimal, and this increases personnel safety. The combustion of the propellant occurs at high pressure, which improves combustion efficiency, and there are thermochemical models for predicting emission products. Components of the motor (such as case, fins, and electronics) can be recovered after treatment. There are, however, some important disadvantages. As in all processes carried out in the open, atmospheric emissions are not treated before release into the environment. With respect to two rocket motor systems that contained a lead burn-rate modifier, as does the M28 propellant in the rocket motors separated from M55 rockets, it was one committee member's direct experience that a nontrivial fraction of the lead remained in the case after treatment. The committee believes that it would be prudent to expect that the motor case will require assessment as hazardous waste because of lead contamination in addition to being managed as MPPEH. There is a potential for propellant cracking, slumping, shrinking, or changing in density as the propellant ages. Those phenomena can change the propellant surface area during burning. In extreme cases, they can result in overpressurization and catastrophic failure of the rocket motor. Such a failure can damage facilities and may initiate a re-evaluation of procedures. This is a mature technology that is commonly used for munitions demilitarization. Throughput will be limited by environmental permits, the number of motors strapped to a test stand, and the time necessary to wire the initiation circuitry. 25

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Contained Thermal Technologies Contained Detonation Contained detonation involves the detonation of the rocket motor or the rocket motor propellant in a sealed chamber. Contained detonation technologies often use a donor explosive charge to detonate the propellant. Afterburning reactions are often quenched as a result of efforts to protect the integrity of the chamber. After detonation, gases in the chamber are passed through a pollution-abatement system to remove contaminants before venting to the local atmosphere. To preserve the detonation chamber, limits are placed on the quantity of energetic material that can be treated in a single detonation, and this restricts process throughput. Designs for contained detonation units are commercially available. This technology has some advantages, such as minimization of the handling of the items being disposed of. Furthermore, emissions are treated before release into the environment. It also has several disadvantages. Over time, shrapnel can cause damage to the facility and result in repair costs and possibly an interruption of processing. That and other stressors also limit the lifetime of the detonation chamber. Large scrap residues need to be removed after each treatment event to minimize the production of shrapnel. The time needed for such clearance limits throughput of the technology. Toxic metal, semivolatile, and nonvolatile emissions from the ordnance will contaminate the interior of the detonation chamber. In the case of the separated rocket motors, such contaminants would include the lead compounds from the M28 propellant. The contaminants would pose a safety risk to personnel operating in the chamber. In addition, it is difficult to ensure that a detonation chamber will remain leakproof over a lifetime of contained detonations; avoidance of environmental contamination requires regular checks for leaks. Contained Combustion Contained combustion involves the burning of energetics in burn pans in a sealed combustion chamber. Gaseous and particulate emissions from the combustion process are stored in a holding tank for later processing before release into the environment. Handling is minimized, but gas storage capacity can be a limiting factor. The time required for postcombustion cleanup of the combustion chamber may decrease processing throughput. The minimization of handling and the treatment of emissions before environmental release are advantages of this technology. However, as with contained detonation, emissions of toxic metals, semivolatile compounds, and nonvolatile compounds from the ordnance will contaminate the interior of the chamber and pose a risk to personnel safety, and lead compounds would be a contaminant from the combustion of M28 propellant. In addition, residues will require assessment for treatment as hazardous waste, and metal scrap must be managed as MPPEH. Throughput will be limited by workplace cleanliness standards and the time needed to treat collected combustion gases. 26

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Contained Static Firing Contained static firing involves the burning of an intact rocket motor or propellant in a combustion chamber. Gaseous and particulate emissions from the combustion process are stored in a holding tank for later processing before release into the environment. Handling is minimized, but gas storage capacity and the potential for damage from a catastrophic failure limit throughput. Minimization of handling and treatment of emissions before environmental release are advantages of this technology. However, the motor residues would need to be removed after each treatment event, and this will limit process throughput. As with contained detonation and contained combustion, emissions of toxic metals, semivolatile compounds, and nonvolatile compounds from the ordnance will contaminate the interior of the chamber and pose a risk to personnel safety. As above, one of the contaminants in disposal of the M28 propellant will be lead compounds. Motor residues will require assessment for treatment as hazardous waste, at least in part because of the presence of lead compounds, and as MPPEH. There is a potential for propellant cracking, slumping, or shrinking and changes in density as the propellant ages. Those phenomena can change the propellant surface area during burning. In extreme cases, that can result in overpressurization and catastrophic failure of the rocket motor. Such a failure can damage facilities and may initiate a re-evaluation of procedures. This technology is commercially available. Confined Combustion Confined combustion burns a rocket motor in a combustion chamber and, in contrast with contained combustion, passes product gases through a pollution-abatement system to remove atmospheric pollutants before release into the environment. Few commercial pollution-abatement systems can handle the large changes in temperature, pressure, and flow rate that occur over the short period of rocket motor combustion. Throughput is limited by requirements for setup and chamber cleanup between motor firings. As with contained combustion, advantages of this technology include the minimization of handling and the treatment of emissions before environmental release. The limited availability of commercial pollution-abatement systems that have the capacity to handle the operational environment of this technology is a potential disadvantage. The motor case needs to be removed from the chamber after each treatment event to minimize damage to the chamber from flying debris and thus prevent shutdown of the unit, which would limit throughput. Emissions of toxic inorganic, semivolatile, and nonvolatile chemicals from the ordnance will contaminate the interior of the chamber and pose a risk to personnel safety. The motor case will require assessment for treatment as hazardous waste at least in part because of the presence of lead compounds and will also need to be managed as MPPEH. This technology has undergone subscale and pilot-scale demonstration. Further development is needed to make it directly applicable to the disposal of rocket motors separated from M55 rockets. 27

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Other Thermal Disposal Technologies Various other thermal technologies have been applied to the demilitarization and disposal of solid propellant rocket motors. They include incineration by rotary kiln, plasma arc, and fluidized bed technologies. As a group, the techniques involve the placement of the propellant or rocket motor into an externally heated chamber and then thermally induced detonation, deflagration, or combustion of the energetic material. Chamber walls are designed to contain the detonation products and shrapnel. Atmospheric emissions are typically passed through commercial pollution abatement systems before release into the environment. Thermal technologies are commercially available from various sources. Four explosive destruction technologies (EDTs) have been and are being evaluated for disposal of the rocket motors separated from the M55 rockets stored at BGAD and for other uses in chemical demilitarization and disposal processes.3 These EDTs are a subset of the conventional demilitarization and disposal technologies described in this chapter. The EDTs can be used to implement contained burning, detonation, or perhaps static-firing technologies. They are called out separately because they are already familiar to the Blue Grass Chemical Agent-Destruction Pilot Plant (BGCAPP) project staff, the public around BGAD, and some state regulators. The four EDTs are as follows: Detonation of Ammunition in a Vacuum Integrated Chamber (DAVINCH), such as the DAVINCH DV65 manufactured by Kobe Steel, Ltd. This process would involve the detonation of a separated rocket motor with a donor explosive in an evacuated chamber that will withstand the detonation. Emissions are treated with a pollution-abatement system. A larger version of the DV65, the proposed DV120, would have a throughput of 36 separated rocket motors in a 10-hour day (NRC, 2009). Sandia National Laboratory's Explosive Destruction System (the EDS-1 and EDS-2). This contained detonation process would involve the detonation of a separated rocket motor with a donor explosive in a chamber designed to withstand the blast and contain the shrapnel and gases and then treatment of the emissions. Currently available EDS units are designed to contain the explosive force from not more than 4.8 lb TNT-equivalent net explosive weight and thus do not have the capacity to treat intact M55 separated rocket motors (NRC, 2009). In addition, the EDS is designed to crack open munition casings to access chemical agent fills and then chemically neutralize the agent. It is not designed primarily for the disposal of energetic materials. The Static Detonation Chamber, such as the SDC 2000 from Dynasafe AB. Energetic materials are dropped into a preheated blast chamber, where they burn, deflagrate, or detonate. Shrapnel is contained in the blast chamber, and gaseous emissions are passed to a holding tank for treatment. Dynasafe has proposed an enlarged version of the SDC 2000 to treat about 100 separated rocket motors in a 10-hour day (NRC 2009). An SDC has been used at the 3 See NRC, 2006 and NRC, 2009 for more detailed information. 28

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Anniston Chemical Agent Disposal Facility to dispose of overpacked and problem munitions that could not be readily processed through the facility. Detonation chambers, such as the Transportable Detonation Chamber and the Contained Detonation Chamber, manufactured by CH2M HILL. As constructed, these are contained detonation chambers. CH2M HILL has proposed using a modified version of the D-100 chamber currently installed at BGAD as a contained static-firing chamber in which separated rocket motors would be fired in their design mode into a containment vessel before treatment of the exhaust products. It has been estimated that this approach would permit the treatment of 180 separated rocket motors in a 10-hour day (NRC 2009). A Transportable Detonation Chamber was used at Schofield Barracks, Hawaii, to dispose of recovered chemical weapons materiel. CHEMICAL TECHNOLOGIES Base Hydrolysis In base hydrolysis, energetic waste is added to water at a mild temperature (90 150C) and high pressure (200 psig) with a strong base (pH > 12). Organic components of the energetic waste are converted to water-soluble nonenergetic materials. The feed rate needs to be controlled to prevent a violent exothermic reaction, that is, deflagration or detonation of the propellant. To control the feed rate and ensure efficient and thorough reaction, it is usually necessary to add propellant to the caustic solution as a slurry. A key advantage of this technology is that energetic waste is converted to water-soluble nonenergetic products, but the resulting solution is still hazardous and must be treated further. Supercritical Water Oxidation Supercritical water oxidation treatment (SCWO) involves addition of a powdered, liquid, or aqueous slurry of energetic waste to a solution of water and an oxidizer at high temperature (over 374C) and high pressure (over 3,000 psig). The organic waste is broken down to water-soluble, nonenergetic materials. Inorganic waste components, such as lead, are oxidized to insoluble salts that can be filtered out of the waste stream. SCWO is already being installed at BGCAPP to treat the products of the chemical neutralization of chemical agent and energetic materials. Use of this technique on the M28 propellant will require some preprocessing to get the energetic into an amenable form. An advantage of this technology is that all organic chemicals are fully decomposed and inorganic materials can be filtered out of the process stream. However, the feedstock is usually in the form of a liquid or slurry, so it would be necessary to remove propellant from motor and pretreat it to get it into an appropriate form; this increases the amount of handling required with the concomitant risks. This is a commercial technology that has been used on a pilot scale to treat waste energetics. 29

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Humic Acid Treatment Humic acid treatment involves heating the propellant in a vat that contains a mixture of caustic and humic acids. Phosphate is usually added to immobilize heavy metals. The resulting products can usually be used as fertilizer, but application of the technique to M28 rocket propellant disposal would require experimentation to verify that lead in the propellant remains immobile and that other toxins are thoroughly destroyed. The production of fertilizer could be an advantage of this technology. However, the presence of lead and other toxins in the propellant could hinder the manufacture of fertilizer. Furthermore the technique has been applied to only a few propellant formulations. Where it has been successful, substantial work has been required to achieve that success. The committee is not aware that humic acid has been used to treat a propellant similar to the M28 propellant in the M55 rockets, and there is a lack of data with which to assess whether it would be successful in treating this propellant. The technology has been demonstrated on a pilot scale. SUMMARY Table 3-1 shows a comparison of advantages and disadvantages of each technology described here, and Table 3-2 presents the committee's judgment of technology status and identifies technology developers or users. Regardless of where the propellant is demilitarized, the selected facility must deal with handling, treatment, and transportation of the propellant and with any political and treaty issues involved with items derived from chemical weapons. Most of the facilities listed in Table 3-2 have not been used to demilitarize rocket motors derived from chemical weapons. Table 3-2 presents estimated process throughputs for each technology on which such information was available. It has been estimated (see Chapter 4) that a separated rocket motor processing throughput rate of 167 motors per day will be needed to keep pace with M55 rocket processing at BGCAPP. Open thermal technologies result in atmospheric releases of respirable lead dust from the M28 propellant. That may place an additional constraint on the throughput of these technologies. For instance, although a facility may be able to process sufficient net explosive weight to dispose of 167 or more separated rocket motors per day, permit restrictions on lead releases could potentially result in much lower throughput. Contained thermal technologies, such as the EDTs, will prevent the release of lead into the environment. The estimated throughput for any of the EDTs has yet to be validated. A detailed consideration of public sentiment about disposal technologies is beyond the scope of this committee's work, but the public around BGAD, although now closely involved in discussions about key project decisions, has historically used political and permitting processes to attempt to achieve the outcomes that they desired. Thus, the committee recognizes that public sentiment, albeit a nontechnical issue, could be an important factor in how readily any disposal technology can be implemented and believes that it should be mentioned in this report. 30

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The public around BGAD has been strongly opposed to the use of incineration to dispose of chemical munitions and the resulting waste streams, such as the separated rocket motors. The public around BGAD is strongly committed to disposing of as much material as possible at BGCAPP by chemical neutralization followed by SCWO. However, willingness to consider the use of alternative technologies, such as the EDTs, in limited applications where safety and other compelling concerns point to them as the best options has been developing. That subject is covered in more depth in Appendix B. A key concern of the public around BGAD has been the release of toxic materials into the environment. Complete containment of emissions from disposal processes is very important to the public. That might indicate that, overall, a contained technology might be more easily implemented than an open technology. Finding 3-4. Thermal treatment demilitarization and disposal operations performed in a chamber require the least handling and permit treatment of product emissions. Chemical technologies either are not mature or are not readily implementable for the disposal of the separated rocket motors. Finding 3-5. The presence of lead in the M28 propellant may significantly constrain the throughput rate for disposing of separated rocket motors with open thermal technologies because of permit limits on the environmental release of lead. Finding 3-6. The public around the Blue Grass Army Depot has historically been concerned about the release of toxic materials into the environment. Public concerns have been important in the disposal of chemical munitions and related wastes. They could also affect how readily a technology for the disposal of separated rocket motors could be implemented. Finding 3-7. A contained thermal technology is the best option for disposing of the rocket motors separated from the M55 rockets stored at the Blue Grass Army Depot. 31

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TABLE 3-1 Technology Comparison Technology Description Advantages Disadvantages Open Ordnance is placed on a pile, Handling is minimized. Atmospheric emissions are not treated further. detonation surrounded with donor explosive, Secondary waste streams are limited to Potential releases of respirable heavy-metal and detonated. unreacted materials, mostly metal case particles from the rocket motor or soil. components. Unreacted materials can be distributed over a Sufficient data are present in emissions large area. databases to permit estimation of process emissions. Efforts to improve the databases are under way. Buried Propellants and donor are buried Handling is minimized. Atmospheric emissions are not treated further. detonation under 48 ft of soil and detonated. Noise is less than for open detonation. The presence of large quantities of soil in the plume suppresses afterburning and increases concentrations of products of incomplete 32 combustion. Little work has been done to quantify this phenomenon, but tests to collect pertinent data are under way. There is a potential for environmental releases of metals and organic chemicals from soil and ordnance. Open burning Loose propellant is placed into a Components of the missile are removed before Emissions are not processed further. pan and initiated. Some facilities treatment. Most propellants are designed to burn efficiently use an additional fuel (e.g. JP-8) Data in emissions databases permit estimation at high pressure. Burning at atmospheric pressure to initiate and support combustion. of process emissions. Efforts to improve the results in incomplete combustion. Some facilities initiate the process databases are under way. by cracking open a rocket motor There would be atmospheric releases of case with a shaped charge. respirable heavy metals (e.g., lead) from the propellant. Rocket motors require prior removal of the propellant from the case to prevent the possibility 32

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TABLE 3-1 Continued Technology Description Advantages Disadvantages of propulsive events; this increases ordnance handling. Ash from the process must be treated as MPPEHa and is probably laden with heavy metals. Open static The rocket motor is secured, then Handling is minimized. Atmospheric emissions are not treated further. firing initiated in its design mode. Combustion occurs at high pressure, and this A nontrivial fraction of lead in the propellant improves efficiency. remains in the carcass after treatment in the form of lead metal and lead oxide dust. There are thermochemical models for predicting emission products. The carcass will require assessment as hazardous waste and MPPEH.a Components of the rocket motor (such as case, fins, and electronics) can be recovered after Aged propellant can crack, slump, shrink, or treatment. change density. In extreme cases, that can result 33 in overpressurization of the motor bottle after ignition, which can lead to catastrophic failure of the rocket motor. Such a failure can damage facilities and may initiate a re-evaluation of procedures. Contained An ordnance item or energetic Handling is minimized. Over time, shrapnel can damage the facility and detonation component is placed into a sealed limit facility lifetime. Emissions are treated before release into the detonation chamber. A donor environment. Large residues need to be removed after each charge is often required. The treatment event to minimize shrapnel. detonation reaction is initiated. Afterburning reactions are often Emissions of toxic metal, semivolatile chemicals, quenched as a result of efforts to or nonvolatile chemicals from the ordnance will protect the integrity of the contaminate the interior of the detonation chamber. After detonation, chamber. product gases and particles are passed through pollution control Regular leak checks are needed to prevent instrumentation to remove environmental contamination as the detonation undesirable contaminants. chamber ages. 33

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TABLE 3-1 Continued Technology Description Advantages Disadvantages Contained Propellant is placed into a pan in a Handling is minimized. Large residues need to be removed after each combustion combustion chamber and initiated. treatment event to minimize damage to the Emissions are treated before environmental Product gases are collected in a chamber from flying debris. release. holding tank and then processed Emissions of toxic metal, semivolatile chemicals, through a pollution abatement and nonvolatile chemicals from the combustion system. will contaminate the interior of the burn chamber. The carcass will require assessment as hazardous waste and MPPEH.a Contained The rocket motor is secured and Handling is minimized. A nontrivial fraction of lead in the propellant static firing fired into a containment vessel in remains in the carcass after treatment in the form Combustion occurs at high pressure, and this its design mode. After of lead metal and lead oxide dust. improves efficiency. combustion, atmospheric Emissions of toxic metal, semivolatile chemicals, contaminants are processed Emissions are treated before environmental 34 and nonvolatile chemicals from the combustion through a pollution abatement release. will contaminate the interior of the burn system. chamber. The carcass will require assessment as hazardous waste and MPPEH.a Aged propellant can crack, slump, shrink, or change density. In extreme cases, that can result in overpressurization of the motor bottle after ignition and lead to catastrophic failure of the rocket motor. Such a failure can damage facilities and may initiate a re-evaluation of procedures. Confined A rocket motor is placed into a Handling is minimized. Few commercial atmospheric filtration devices combustion combustion chamber and initiated. are capable of real-time handling of the changes Emissions are treated before environmental Product gases are not contained in temperature, pressure, and flow rate that occur release. but are passed immediately during a motor firing. through pollution abatement Large residues need to be removed after each 34

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TABLE 3-1 Continued Technology Description Advantages Disadvantages equipment before release into the treatment event to minimize damage to the environment. chamber from flying debris. Work at China Lake involved Emissions of toxic metal, semivolatile chemicals, burning of full-scale rocket and nonvolatile chemicals from the ordnance motors with the nozzle removed. combustion will contaminate the interior of the burn chamber. The carcass will require assessment for treatment as hazardous waste and MPPEH.a Rotary kiln This is an enclosed incinerator in High feed rates have been demonstrated. Deflagration or detonation of energetic materials which waste is slowly moved can damage facilities and interrupt operations. Emissions are treated. from one end to the other. Waste Few atmospheric filtration devices are capable of material detonates or combusts. handling the extreme changes in pressure and Emissions are treated. flow rate that occur during a large detonation event; this will limit the treatment rate. 35 Careful control of feedstock and combustion conditions is needed to minimize production of toxins like dioxins. Fluidized bed Energetic waste is injected into a Emissions can be treated. The technique is limited to liquids, slurries, and turbulent bed of hot sand. powders that have low inorganic content. Substantial handling is needed to remove solid propellants and convert them to a form amenable to treatment. Static Ordnance is dropped into a heated Handling is minimized. The furnace will need to be turned off regularly Detonation chamber, where it detonates, to empty the chamber of collected incombustible Emissions are scrubbed. Chamberb deflagrates, or combusts. Product residues. gases are scrubbed with a Residues from rocket motors separated from pollution abatement system. M55 rockets will probably be contaminated with 35

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TABLE 3-1 Continued Technology Description Advantages Disadvantages lead and require lead abatement to handle. Facility lifetime is limited by damage to the detonation chamber from shrapnel. Base Energetic wastes are added to Energetic waste is converted to water-soluble The resulting solution is still hazardous and must hydrolysis water and heated to mild nonenergetic products. be treated further. temperatures (90150C) usually Careful control of feed rate is needed to prevent at high pressure (200 psig) with a the deflagration or detonation of propellant. strong base (pH > 12); this chemically degrades the energetic materials. Supercritical Organic waste, water, and an Organic chemicals are decomposed. Feedstock is usually in the form of a liquid or 36 water oxidizer (such as hydrogen slurry. It is necessary to remove propellant from oxidation peroxide) are subjected to high the motor and pretreat it to get it into an temperature (>374C) and appropriate form. pressure (>3,000 psig); this chemically degrades the organic waste. Humic acid Energetics are heated in a vat that Product is fertilizer. Used to date only on a few propellants. treatment contains a mixture of caustic and The record of success is mixed. humic acids. Phosphate is usually added to immobilize heavy The method might require much work for metals. application to M28 propellant. There is a lack of data with which to assess the likelihood that the technology will work on M28 propellant. a MPPEH, materials potentially presenting an explosive hazard. b See discussion in section "Other Thermal Disposal Technologies". 36

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TABLE 3-2 Technology Status and Applicability Technology developer or Estimated M55 rocket motor Technology Technology status representative user throughputa Open Mature Naval Air Weapons Station, N/A detonation China Lake (user) Hill Air Force Base (user) N/A Buried Mature Tooele Army Depot (user) N/A detonation Defense Ammunition Center N/A (user) Anniston Army Depot (user) N/A Open burning Mature Naval Surface Warfare Center, N/A Indian Head (user) BGAD (user) 300 per event Open static Mature Tooele Army Depot (user) N/A firing Anniston Army Depot (user) N/A McAlester Army Ammunition Plant (user) Contained Commercially Naval Surface Warfare Center, N/A detonation available Crane (developer and user) Tooele Chemical Agent N/A Destruction Facility (user, DAVINCH DV65) CH2M HILL (developer, D-100 N/A Detonation Chamber) Kobe Steel (developer, 36 per day for the Kobe DAVINCH) Steel DAVINCH DV120 (NRC, 2009) Contained Commercially Naval Surface Warfare Center, N/A combustion available Crane (developer and user) Naval Surface Warfare Center, N/A Indian Head (developer and user) CH2M Hill (developer) N/A Contained static Commercially Naval Air Warfare Center, China N/A firing available Lake, in partnership with Lockheed-Martin (developer) El Dorado Engineering N/A 37

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TABLE 3-2 Continued Technology developer or Estimated M55 rocket motor Technology Technology status representative user throughputa (developer) CH2M Hill (developer, D-100 180 per day for static firing Detonation Chamber) in the CH2M HILL D-100 Detonation Chamber (NRC, 2009) Confined Sub-pilot and pilot Naval Air Warfare Center, China N/A combustion scale Lake, in partnership with Lockheed-Martin and Bechtel (developer) Rotary kiln Commercially Tooele Army Depot (user) N/A available for small munitions Fluidized bed Pilot scale Defense Ammunition Center N/A (user) Static Commercially Anniston Chemical Agent Detonation available Disposal Facility (user) 100 per day, upgraded SDC- Chamber Dynasafe AB (developer) 2000 (NRC, 2009) Base hydrolysis Commercial process Defense Ammunition Center N/A (user) Supercritical Commercial process Defense Ammunition Center N/A water oxidation (user) Humic acid Pilot-scale Defense Ammunition Center N/A treatment demonstration (user) a Estimate based on a 10-hour workday. REFERENCES DoD (Department of Defense). 2008. Department of Defense Instruction: Material Potentially Presenting an Explosive Hazard, Number 4140.62, November 25. Available online at http://www.dtic.mil/whs/directives/corres/pdf/414062p.pdf. Last accessed on May 17, 2012. DoD. 2011. Department of Defense Manual: Defense Demilitarization, 4160.28-M, Volume 13, June 7. Fort Belvoir, Va.: Defense Technical Information Center. 38

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EPA (Environmental Protection Agency). 2009. AP 42: Compilation of Air Pollutant Emission Factors, volume 1, chapter 15, Ordnance Detonation. Fifth Edition. Available online at http://www.epa.gov/ttn/chief/ap42/ch15/index.html. Last accessed on May 17, 2012. Erickson, E.D., A.P. Chafin, T.L. Boggs, L.A. Zellmer, and B.M. Abernathy. 2005. Emissions from the Energetic Component of Energetic Wastes During Treatment by Open Detonation, NAWCWD TP 8603, June. China Lake, Calif.: Naval Air Warfare Center Weapons Division. Kim, B.J. 2010. Feasibility of New Technology to Comprehensively Characterize Air Emissions from Full Scale Open Burning and Open Detonation, SERDP Project WP- 1672, Final Report, December. Available online at http://www.serdp.org/ content/download/9560/122378/file/WP-1672-FR.pdf. Last accessed on May 17, 2012. NRC (National Research Council). 2006. Review of International Technologies for Destruction of Recovered Chemical Warfare Materiel. Available online at http://www.nap.edu/catalog.php?record_id=11777. Last accessed on June 29, 2012. NRC. 2009. Assessment of Explosive Destruction Technologies for Specific Munitions at the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants. Available online at http://www.nap.edu/catalog.php? record_id=12482. Last accessed on May 17, 2012. Wright, J., E. Erickson, and G. Thompson. 2010. Open Detonation (OD) Emission Factor Development. Presentation to the 18th Annual Global Demilitarization Symposium and Exhibition. May 10-13, Tulsa, Okla. 39

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