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Purpose

1. The health and environmental consequences of using DU on the battlefield

2. Which remediation technologies exist or might be developed to clean up DU contamination

3. Ways to reduce DU toxicity

4. How to best protect the environment from the long-term consequences of DU use.

Although this report does not directly address DU weapon systems produced by the Department of Energy (DOE) or used by other cervices (i.e., the Air Force or Navy), the health and environmental consequences associated with using these systems should be similar.

If providing the fighting soldier with the maximum battlefield advantage means using DU, then methods to minimize potential health and environmental consequences must be employed. It should be noted that under current international law, there is no legal requirement to remediate environmental damage to battlefields. Furthermore, it is unlikely that future remediation of battlefields solely to remove DU will be required.Ý

The DU Production Process

Depleted uranium is a byproduct of fuel- and weapons-grade uranium refining. While naturally occurring uranium, a radioactive element, contains a small amount of the isotope ²³⁵U, nuclear power requires greater concentrations of ²³⁵U to sustain the nuclear chain reaction. The process to concentrate the ²³⁵U is called enrichment. One byproduct of the enrichment process is depleted uranium. DU retains uranium's natural toxicological properties and approximately half of its radiological activity. As such, DU is treated as low-level radioactive material and, when discarded, is considered a low-level radioactive waste (LLRW). It fits into the lowest LLRW hazard class.

When properly managed, low-level radioactive waste does not present a significant chemical or external radiological hazard.

Commercially, DU is used in medicine, space, aviation and petroleum exploration. Particular applications include radiation shielding for the medical field and industry; counterweight components of aircraft elevators, landing gear, rotor blades and radar antennae; ballast in satellites, missiles and other crafts; and drilling equipment used in petroleum exploration.

In military applications, when alloyed, DU is ideal for use in armor penetrators. The photo shows a typical DU cartridge and penetrator. These solid metal projectiles have the speed, mass and physical properties to perform exceptionally well against armored targets. DU provides a substantial performance advantage, well above other competing materials. This allows DU penetrators to defeat an armored target at a significantly greater distance. Also, DU's density and physical properties make it ideal for use as armor plate. DU has been used in Army systems for many years in both applications. Over the past 20 years, the Department of the Army (DA) has developed, tested and fielded a number of weapon systems containing DU. The United States is not alone. The United Kingdom, Russia, Turkey, Saudi Arabia, Pakistan, Thailand, Israel, France and others are developing or already have DU-containing weapon systems in their inventories. The use of DU weapons and armor during Desert Shield/Desert Storm has led to public concern over the health and environmental risks of DU. As a result of friendly fire incidents, approximately 22 soldiers from Desert Storm may have retained embedded DU fragments. This is a combat injury never before encountered. Additionally, a January 1993 General Accounting Office (GAO) report found that the Army did not have a comprehensive DU battlefield management plan. This study also reported that Desert Storm recovery and maintenance soldiers worked in and around DU-contaminated equipment without being aware of their potential exposure and without being appropriately trained in protective measures. The GAO also reported that Army training on DU safety is not routinely provided to many personnel who could come in contact with DU-contaminated equipment.

A typical DU cartridge and penetrator.Ý

During Desert Shield/Desert Storm, the Army fired DU munitions at practice firing ranges and during battle in Southwest Asia. The Army has also tested DU munitions at specific U.S. sites while developing and producing weapon systems.

The Army has considerable experience in managing the environmental issues associated with DU on test ranges in the United States. For many years, the Army has conducted tests in enclosed chambers in which a DU penetrator strikes armor plate (hard target testing). The enclosure precludes the DU containing aerosols (suspensions of small particles that can be generated upon impact) from being transported through the air. Work is ongoing to evaluate if and how DU migrates on the soft-target (cloth or wood and soil impact) test ranges. Experiments have been conducted to determine the extent of contamination resulting from fires in vehicles that contain DU.

Efforts to better define all of these issues are in progress. Specifically, environmental fate and effect studies designed to assess the risks of residual DU on the ranges will be expanded to include transport models to more accurately evaluate environmental risks. The Army has had active DU range recovery programs, designed to remove DU from the environment, in place for many years. These programs are continually being improved.

Because Desert Shield/Desert Storm was the first battlefield use of DU, the Army is considering all of the experiences gained to develop programs that will address issues identified during and after the conflict. Generalized environmental risk/cost policy models are being considered to enhance fate and effect evaluation of DU migration across many soil and environmental conditions. Additional data on DU particulates generated during hard-target hits and DU-containing fires will be required for these models. These data also will improve health effect models for wound contamination and inhalation exposures. Finally, data exchanges are being pursued with other countries to minimize the costs and to maximize the accuracy of environmental models that can be used to better assess the impacts of DU on the environment and human health.

The first U.S. battlefield use of DU has clearly presented new areas requiring attention, including the need for more data on potential health and environmental consequences associated with the chemical and radiological characteristics of DU. A significant effort is underway to evaluate the long-term health risks to the U. S. soldier in light of the acknowledged characteristics that make DU desirable for use in weapon systems. Thirty-six U.S. soldiers (including the 22 suspected of retaining embedded fragments) have sought or reported for medical treatment as a result of being in vehicles that were struck by DU munitions. The Army and the Department of Veterans Affairs (DVA) have, with the assistance of the Armed Forces Radiobiology Research Institute (AFRRI), initiated a peer-reviewed program designed to provide health care monitoring and treatment for individuals suspected of incurring injuries from, or internal exposure to, DU. These soldiers will be monitored for at least five years.

The Army Environmental Policy Institute examined the life cycle of DU in Army weapon systems, which includes penetrators and tank armor. The purpose of this study was not to verify the technical performance of DU weapon systems; the study accepts as fact that the superior performance characteristics of DU precipitated informed decisions about weapon selection. Instead, this report assesses the health and environmental effects associated with the use of DU.Ý

Previous Research

The Department of Defense (DoD) and the Department of the Army, prior to fielding DU-containing weapon systems, considered the health and environmental consequences, based upon two independent and three internal investigations:

• The National Materials Advisory Board of the National Research Council (part of the National Academy of Sciences) conducted two independent assessments of DU. The first, a generic assessment conducted in 1971, and the second, a specific assessment completed in 1979, compared DU penetrators with tungsten penetrators, the next best alternative.

• Between 1974 and 1989, DoD and DA commissioned three studies on the health and environmental effects of DU. The Office of the Director, Defense Research and Engineering, tasked the Joint Technical Coordinating Group for Munitions Effectiveness to perform an initial assessment to ". . . evaluate the medical and environmental implications of the use of depleted uranium (DU) and alternatives in a variety of conventional munitions." This review was published in 1974. The former Assistant Secretary of the Army, the Honorable Percy Pierre, requested the second study. A group of primarily non-DoD scientists prepared the Pierre Report, published in 1979. A group of DoD and non-DoD scientists completed the third study, the Danesi Report, at the request of the Army Materiel Command. It was published in 1989.

Conclusions from the AEPI study, concerning both environmental and health impacts related to Army use of DU, support previous findings and are summarized in the remainder of this section.

Health Risks-Peacetime Operations.

The health risks associated with using DU in peacetime are minimal. This includes risks associated with transporting, storing and handling intact DU munitions and armor during peacetime. The risks are within current safety and health standards and are controlled by the Army's radiation protection program.

An enclosed DU firing range, known as a "Superbox," prevents aerosols containing DU from entering the air outside the chamber during testing.

Health Risks-Battlefield Operations.

A review of the experimental data and the lessons learned in Operation Desert Storm led to the following conclusions:

• It is highly unlikely that DU is a contributing factor to the unexplained illnesses currently being reported by veterans of Desert Storm. This conclusion is based on the assessment that there was little or no internal DU exposure by most Desert Storm soldiers.

• The potential for health effects from external DU exposure during combat operations is not significantly greater than the potential during peacetime operations.

• The friendly fire incidents that occurred during Desert Storm showed that personnel in armored vehicles can survive DU penetrations of their vehicles but that they can have medically significant internal DU exposure from embedded fragments, wound contamination and inhaled aerosols.

• The Office of the Army Surgeon General believes that the long-term health effects of embedded DU fragments have not been well defined but are minimal. The long-term medical follow-up of veterans with embedded DU fragments is in progress and will continue. In most instances, the DU fragments were allowed to remain embedded because the number and location of those fragments made the risks of physical removal significant. These cases will initially be monitored in a five-year study by the Army and the DVA. If necessary, the Army will monitor these patients for longer periods. Monitoring data will be used to better define the risks from embedded DU fragments.

• It is unlikely that recovery and maintenance personnel working in and around vehicles impacted by DU penetrators received significant internal DU exposure. Because the risks have not been well defined, the Army is monitoring those soldiers who worked extensively with DU-contaminated vehicles and may have sustained exposure. Data from these studies will be used to develop models that predict health risks and to design protective measures, if required, for maintenance and recovery personnel. It is unlikely that significant internal exposures occurred to other individuals who either had incidental contact with contaminated vehicles or breathed smoke from the plumes from burning vehicles impacted by DU penetrators. These scenarios, however, should be evaluated to quantify the risks.

A number of studies concerning the environmental risks of the peacetime uses of DU have been accomplished. Following are the major points identified concerning risks during peacetime operations:

• The Army has been aggressive in managing DU on test ranges to reduce the environmental contamination at these facilities and has initiated programs to model the environmental fate and effects of DU. The effectiveness of these programs could be improved by more comprehensive modeling and experimentation efforts.

• The Army continues to develop policies and procedures for recovering and managing DU-contaminated test areas. Additional data are required to evaluate and enhance the effectiveness of these policies and procedures.

• The Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and other environmental laws and regulations that the Environmental Protection Agency (EPA) and Nuclear Regulatory Commission (NRC) administer require that all federal lands, including test ranges, be cleaned up before they are released for unrestricted use under the Base Realignment and Closure program. The environmental impacts of remediation alternatives will be considered in determining future land use.

The major points identified in this study concerning battlefield operations follow:

• The postwar battlefield is a dangerous place. It is contaminated with many environmentally harmful substances.

• The impact of DU and other contamination on the battlefield is not well defined. Relative to many of the other hazards, however, the DU impact is probably small.

• Any guidance the United States provides, consistent with U.S. foreign policy, to affected nations to assist them in cleaning up battlefield debris should be based upon our best estimate of the short- and long-term environmental consequences. DU management should be included as part of any remediation program recommended to a host nation to mitigate environmental damage on the battlefield.

• The potential for major environmental impact from DU contamination on battlefield sites is low. Additional environmental modeling and data are needed, however, to support this judgment.

Very few technologies have been applied to remediate sites contaminated with DU. There is a paucity of data on the success of these efforts. However, DU is a heavy metal, and many of the technologies used for segregating other heavy metals such as gold, lead and cadmium may be effective in cleaning up DU.

Measures to Reduce DU Toxicity.

The inherent chemical and radiological toxicity of DU cannot be significantly changed. DU must be managed carefully and appropriately in light of these risks.Ý

Uranium/Depleted Uranium Properties and Characteristics

DU is Chemically Similar to Uranium but is Radiologically Different.

Uranium is a radioactive heavy metal nearly agencies also evaluate these systems relative to their twice as dense as lead. It occurs naturally in a variety of forms. Uranium readily combines with other elements to make uranium oxides, silicates, carbonates and hydroxides. It can be purposely combined with other metals to create readily machinable, high strength alloys.

Small particles of uranium metal can ignite spontaneously in air and can burn rapidly at very high temperatures.

Three naturally occurring isotopes of uranium are found in the earth's crust: uranium-234 (²³⁴U), uranium-235 (²³⁵U) and uranium-238 (²³⁸U); each is radioactive. Of these isotopes, ²³⁸U is the most abundant (more than 99 percent of natural uranium) and has the lowest rate of radioactive emission. If the radioactivity of ²³⁸U were equal to one, ²³⁵U would have a radioactivity of approximately seven, while ²³⁴U would have a radioactivity of about 18,000. Thus, ²³⁴U is a major contributor to the radioactivity of natural uranium and DU, though it represents less than one percent of the total weight.

Depleted uranium is a byproduct of the process in which uranium is enriched to become reactor fuel or weapons-grade material. DU is about half as radioactive as naturally occurring uranium because it contains less ²³⁴U and ²³⁵U.

DU Applications and Use

In addition to military weapon systems, DU is used commercially in medicine, aviation, space and petroleum exploration. Particular applications include radiation shielding for the medical field and industry; counterweight components of aircraft elevators, landing gear, rotor blades and radar antennae; ballast in satellites, missiles and other crafts; and drilling equipment used in petroleum exploration. In military applications DU is used in penetrators, armor plate and, in small quantities, as a catalyst in some mines.

Health and Environmental Attributes

Army Program to Review Health and Environmental Effects of All New Systems

The Office of the Army Surgeon General reviews all Army weapon systems to assure all known health issues have been satisfactorily addressed prior to fielding. The program managers and various Army environmental consequences under the criteria in the National Environmental Policy Act (NEPA).

DU Toxicological and Radiological Health Effects.

Like naturally occurring uranium, DU has toxicological and radiological health risks. Toxicologically, DU poses a health risk when internalized. Radiologically, the radiation emitted by DU results in health risks from both external and internal exposures; however, the external exposure risk is very low. The magnitude of the toxicological and radiological health risks of internalized DU is dependent on the amount internalized, the chemical form and the route of entry into the body. DU can be internalized through inhalation, ingestion, wound contamination and, as in the case of DU fragments, injection. Both non-combat and combat scenarios can lead to DU health risks.

In non-combat scenarios, inhalation can occur during DU munitions testing, during accidental fires at facilities storing munitions or fires in vehicles loaded with munitions, and during operations that can resuspend DU particulates. Ingestion can occur from hand-to-mouth transfer of contamination or as the result of DU-contaminated food or water. Army safety and health programs are in place to minimize such exposures.

In combat, DU wound contamination and fragment implantation become more significant pathways of entry. The potential for inhalation and ingestion (from DU particles generated when DU penetrators strike armored targets, when DU armor is impacted or when fires consume DU penetrators) also increases. Based on the lessons learned in Desert Storm, the Army is developing procedures to better manage the internal exposure potential for DU during combat. As previously stated, external exposure

impacted by DU penetrators received significant internal DU exposure. Because the risks have not been well defined, the Army is monitoring those soldiers who worked extensively with DU-contaminated vehicles and may have sustained exposure. Data from these studies will be used to develop models that predict health risks and to design protective measures, if required, for maintenance and recovery personnel. It is unlikely that significant internal exposures occurred to other individuals who either had incidental contact with contaminated vehicles or breathed smoke from the plumes from burning vehicles impacted by DU penetrators. These scenarios, however, should be evaluated to quantify the risks.

Radiological exposure to external sources of DU occurs through the proximity of personnel to munitions, armor and contaminated equipment. These are low-level, low-dose-rate exposures that are within current NRC safety and health standards.

Radiological Risks Not Completely Understood but Not Underestimated.

While there are no data that can be used directly to establish the human cancer and hereditary risks from low-level, low-dose radiation, there is general agreement that the models currency in use do not underestimate either the cancer or hereditary risks.

External Exposures Estimated and Found to Be Minimal.

The Army has extensively studied the external exposures that personnel receive during each phase of the DU munitions and armor life cycle. These data were developed based on radiation field strength measurements and time/motion studies used to determine exposure rates and cumulative doses. The Office of the Army Surgeon General fully reviewed all data relative to health assessment. The radiation exposure depends upon the amount of DU, the DU item (penetrator or armor), the configuration (storage, uploaded on a vehicle, exposed penetrator), and the time and distance over which the exposure occurs. The designs of the DU munitions and the DU armor minimize the external exposures to the crews and handlers; the DU is always encased by nonradioactive materials. For all Army DU systems, the exposure to soldiers and civilian employees associated with those systems is less than five percent of the current NRC occupational worker exposure limit of 5,000 millirem per year.

Internal Exposures for Some Personnel Wounded in Friendly Fire Incidents Potentially Significant.

Once internalized, DU delivers radiation exposure to the site of contact, as well as to other organs in the body to which uranium migrates. A number of methods have been developed to determine how DU migrates within the body based on the type of exposure, DU form, time, degree of exposure and pathway of internal migration. Techniques exist to assess the level of uranium internalized by inhalation or ingestion. While some best professional judgment estimates can be made, models to estimate more accurately the radiation exposure from uranium internalized by wound contamination or from embedded DU fragments are not now available.

During Desert Storm some U.S. soldiers unfortunately sustained penetrating wounds in friendly fire incidents. Some of these soldiers had multiple (up to 30) fragments ranging in size from one millimeter to 20 millimeters in diameter in their bodies. Upon review of these injured soldiers' medical records, the Office of the Army Surgeon General identified 22 who may have retained embedded DU fragments. In most instances, the fragments were allowed to remain embedded because the numbers and locations of these fragments made the medical risks associated with surgical removal unacceptable. The Army and DVA will continue to monitor these cases as part of a five-year study.

The Armed Forces Radiobiology Research Institute conducted an extensive literature search on the health effects of allowing DU fragments to remain embedded in the body and concluded that there was no compelling reason to change current surgical criteria for fragment removal. This same study cited two as-yet undefined key uncertainties that could change this recommendation: (1) the long-term radiation effects on the tissue surrounding the fragment and (2) the long-term toxicological effects of embedded DU.

Toxicological Risks Not Completely Understood.

Like most heavy metals, uranium is chemically toxic if sufficient quantities are internalized. Once incorporated, the highest concentrations of uranium are found in the kidneys, liver and bone. The kidney is the most sensitive organ to toxicity. It is important to realize, however, that uranium is found throughout the environment and is naturally incorporated into the body.

The toxicity of internalized DU depends on:

• Amount internalized

• Route of internalization

• Physical characteristics of the DU internalized

• Chemical solubility characteristics of the DU internalized.

Another area of uncertainty concerns exposure of female soldiers to DU. At present, there are no definitive studies on the health and developmental effects on fetuses whose mothers have internalized DU. It is important to note, however, that no female soldiers were involved in the friendly fire incidents and none served on the recovery and maintenance teams.

Chronic kidney toxicity and localized radiation effects are the primary health concerns for Desert Storm veterans wounded by DU fragments. Embedded fragments have resulted in elevated levels of uranium in the blood. These veterans are being monitored by the DVA/Army five-year study.

Definitive Health Risk Conclusions Difficult.

It is difficult to present a conclusive discussion of the risk associated with the exposure to low-level radiation from DU because adverse effects of very low levels of radiation are difficult to document in humans.

Studies summarized by the National Research Council on the effects of low-level exposure did not reveal a significant increase in radiation effects on workers or populations living near nuclear installations, exposed to nuclear weapons fallout, exposed to medical radiation, or living in high natural background radiation areas.

The National Research Council did not discount hereditary or cancer risks associated with low-level radiation exposure, but it did draw two conclusions: (1) the available data did not allow a direct estimate of the risk from low levels of radiation; and (2) the data indicated that current risk estimates do not under estimate the risk and probably represent the upper bound of real risk.

The following should be kept in mind during any consideration of the health effects of low-level radiation:

• The general public is continually exposed to radiation from natural sources. The average annual radiation background exposure in the United States is about 300 millirem from natural sources. The NRC exposure standard for the general public is 100 millirem per year above background.

• It is typically impossible to determine whether a specific cancer or hereditary effect occurred naturally or was the result of low-level radiation exposure. No medical difference exists between naturally occurring or radiation-induced cancer and hereditary effects.

• NRC and EPA have established radiation standards to protect radiation workers and the public from significant risks.

• High local doses, such as those received by tissues surrounding an embedded fragment, do not correlate well with published cancer risk data because these data are typically calculated using whole-organ or whole-body doses. Thus, existing models cannot estimate the health risk to soldiers with y

Because DU and naturally occurring uranium are chemically the same, knowledge about the transformation, transport, fate and effect of natural uranium in the environment is applicable to the study of DU.

Uranium, like other metals, will oxidize under most environmental conditions. Variables such as temperature, metal size and shape, presence or absence of coatings, and water and soil contaminants control the oxidation rate.

Under some conditions, such as those in swamps and wetlands, DU oxidizes to a state where it will not readily dissolve in water and thus becomes relatively immobile. Under other conditions, such as on the surface of the ground or in shallow water, DU oxidizes to a state where it can dissolve and become mobile in water. Small DU particles, such as fragments and abrasion particles, will oxidize faster; large pieces, such as nearly whole penetrators and large fragments, will oxidize more slowly.

Water is the dominant mechanism for transporting all metals, including DU, in the environment; metals may move in surface waters or groundwater. For metals widely dispersed across a land surface, the principal concern is groundwater contamination, although erosion can result in contaminated water runoff to surface streams and ponds. In arid environments, the wind can transport dust contaminated with small DU particles.

The Army has used three principal centers for test firing DU penetrators:

• Aberdeen Proving Ground, Maryland

• Jefferson Proving Ground, Indiana

• Yuma Proving Ground, Arizona

Groundwater at Aberdeen Proving Ground and Jefferson Proving Ground was analyzed; no DU was detected. Groundwater at Yuma has not been analyzed because the semiarid climate and the soil chemistry at Yuma make it unlikely that DU could ever reach the first aquifer at the 700 foot level. At Aberdeen, localized soil contamination was discovered at depths of 20 centimeters (7.9 inches) below a penetrator corroding on the soil surface. This suggested that DU can become soluble and migrate to a limited degree even through soil in a wetland environment. At Yuma, where a high evaporation rate results in little vertical infiltration, soil contamination near a corroding penetrator decreased to back ground levels at a depth of eight centimeters (3.2 inches). Sediment samples in an adjacent drainage channel, however, contained DU, presumably from storm runoff.

Other studies at the firing areas revealed that DU contamination occurs (1) at shallow depths immediately downrange from the gun tube; (2) where penetrators first pass through the soil ("skip" areas); and (3) in the final landing area. The low level of contamination immediately downrange from the gun tube occurs due to fragments from malfunctioning rounds and very low levels of DU emitted during normal firing operations. In the skip areas, soil contamination results from abrasion fragments of the penetrator, and in the final landing area, from corrosion.

Investigations of DU migration at U.S. test sites have not identified significant migration in the environment. It is fortunate that the environmental conditions, particularly the water and soil conditions, at the three major test locations tend to prevent soluble DU containing compounds from forming and thus limit environmental migration. However, because future uses of DU, particularly in combat, will not be restricted to these ranges, the Army is developing risk models to ascertain ways to predict the environmental mobility of DU under any soil condition.

Potential DU External Radiation Exposures Were Below the Annual Limit for the General Public.

During Desert Shield/Desert Storm, the Abrams tank crews were exposed to low levels of DU radiation in the crew compartment from DU armor (Abrams heavy tank only) and from combat ammunition storage. Predictable dose rates for crew members can be determined by combining vehicle occupancy rates with actual radiation measurements. A typical exposure rate inside a tank is 0.1 millirem per hour, thus, a crew member could stay for a total of 1,000 hours per year before exceeding the new NRC 100 millirem annual limit on exposure to the general population.

Detectable amounts of DU are deposited in the gun tube when a DU round is fired. Recently completed studies have determined that such contamination poses no significant health hazard to personnel handling the gun tubes. Studies are underway to determine if any significant migration occurs into the tank crew compartment.

When a DU projectile penetrates an armored vehicle, it may pass completely through the vehicle or ricochet and break into fragments inside the vehicle. In addition to flying metal fragments, crews can be exposed to DU oxides, toxic fumes, smoke and flames. The force of impact will convert a portion of the DU penetrator into aerosols, thereby exposing the crew to respirable particles. The vehicle itself is contaminated with particulates and fragments from the DU penetrator and any DU armor damaged by the impact.

After a battle has been concluded, medical and equipment recovery personnel move onto the field. Damaged U.S. equipment is repaired on site or stripped and/or evacuated to rear maintenance points. Enemy equipment is usually left in place. Equipment contaminated with DU can contaminate personnel and other equipment. DU particulates can be resuspended, blown, washed or dislodged during repair, retrieval or transit.

During Desert Shield/Desert Storm, 15 Bradley Fighting Vehicles and 14 Abrams tanks were contaminated after being hit by DU rounds or after stored DU ammunition ignited due to an accidental onboard fire. In all, 28 of the 29 vehicles were returned to the 144th Service and Supply Company, New Jersey Army National Guard, at King Khalid Military City, Saudi Arabia. The 29th vehicle, an Abrams tank, was damaged by a fire in December 1990 and returned directly to the Defense Consolidation Facility (DCF) in South Carolina in January 1991.

The 144th was responsible for establishing a central receiving and storage point, for assessing battle damage and for preparing the vehicles for return to the United States. Initially, the 144th Service and Supply Company was not familiar with procedures for handling DU-contaminated equipment. For about three weeks, up to 25 soldiers may have worked on the DU-contaminated vehicles. These soldiers did not know that the vehicles were contaminated with DU, nor were they aware of necessary protective measures. An Army recovery team arriving from the United States secured all contaminated vehicles, limited access to them, surveyed the equipment, and instituted protective measures such as wearing dust masks and thin rubber gloves and washing hands, faces and clothing.

After fixed radioactive contamination caused by DU penetrator strikes was removed, six of the Bradleys were buried at an approved site at King Khalid Military City. They were not turned in for scrap because they all had burned and the certifying officer could not declare that there was no unexploded ordnance in the wreckage. (When a Bradley burns, the aluminum armor melts into the center of the vehicle. Once it cools and hardens, the metal may cover unstable live ammunition.) DU-contaminated components, as well as the remaining vehicles, were returned to the Defense Consolidation Facility in South Carolina for decontamination, salvage or return to the repair facilities.

DU Contamination in Southwest Asia.

More than 14,000 large caliber DU rounds were consumed during Operation Desert Shield/Desert Storm. As many as 7,000 of these rounds may have been fired in practice. Approximately 4,000 rounds were reportedly fired in combat. The remaining 3,000 rounds are losses that include a substantial loss in a fire at Dohoa, Saudi Arabia. Between 80 and 90 percent of the DU penetrators fired in combat probably came to rest in or near target vehicles. Rounds that missed probably buried themselves near the intended targets or skipped downrange.

Development tests under field conditions show that the highest level of DU contamination is adjacent to an impacted vehicle. This level of contamination is reduced by 90 percent within the first 30 meters, but trace amounts of DU concentrations have been detected out to 400 meters downwind. Vehicles burned with exploding ammunition under test conditions ejected some fragments as far as 65 meters.

Remediation Technologies

DU remediation technologies under development involve one or more of the following: excavation and earth moving, physical separation, chemical separation, and in-place stabilization. Unless in-place stabilization is selected, earth moving processes are required. The scope of this activity ranges from (l) excavating and disposing of all contaminated soil to (2) excavating, treating and re-emplacing the soil. There are health and environmental hazards associated with any earth moving project. These are compounded by the toxicological and radiological effects of DU and, more importantly for battlefields and most test range sites, unexploded ordnance.

Physical separation techniques use the characteristics of the contaminant (density, particle size, shape, etc.) to segregate it from the soil. These techniques range from simply having personnel pick up DU fragments by hand (a technique the Army commonly uses on its test ranges) through increasingly complex technologies such as screening, sedimentation, centrifugation, filtration and reverse osmosis. Physical separation techniques do not change the state of the contaminant.

A number of chemical treatment processes can be used to separate DU from contaminated soil. Although experience in remediating DU contamination is limited, these processes have long been used to separate other heavy metals (lead, gold, silver, cadmium, chromium, etc.) from soils in mining, industry and environmental remediation. The industry standard is soil washing. Soil washing systems f first pass a fluid through the soil to dissolve the metal. Then the chemistry of the solution is altered, causing the metal to precipitate. The soil can be excavated or treated in place.

For shallow soil contamination, heavy metals can be stabilized in place. This strategy uses a chemical binding agent that reacts with the metal to render it insoluble under a wide range of environmental conditions. Because the chemistry of DU is similar to that of other heavy metals, applying this technology to stabilize DU in the environment can be expected to be similarly successful. The major disadvantage of in-place stabilization is that the metal remains in the soil and thus, under unforeseen circumstances, could again become mobile in the environment.

DU Toxicity Reduction

The Inherent Chemical and Radiological Toxicity of DU Cannot Be Changed.

No technologies available can change the inherent toxicity of DU. The Army uses good management practices, material control and encasement to limit personnel exposure to DU in armor and munitions throughout their life cycles. Once materials are compromised, however, such as when penetrators are fired or armor is pierced, uranium can then react with other elements contiguous to it in the environment. This can create chemical reactions that may yield compounds with various chemical toxicities. Due to the nature of high-energy penetrator impacts, there are no effective measures that can be applied to reduce the toxicity of spent projectiles. Alternative materials for penetrators, such as tungsten, are less effective yet retain many of the inherent toxicity problems of heavy metals evidenced by DU.

Long-Term Environmental Consequences

Issues Concerning DU Environmental Management on the Battlefield.

To give the U.S. soldier the best battlefield advantage, the United States must continue fielding superior weapon systems.

Using DU on the battlefield poses potential environmental consequences. The question is how to protect the environment and thereby reduce the risks to the soldiers and the indigenous population. Efforts are underway to develop a fundamental understanding of the fate and effect of DU in the environment. But even a unilateral decision by the United States to eliminate DU weapons would not remove DU from the battlefield: the United Kingdom, Russia, Turkey, Saudi Arabia, Pakistan, Thailand, Israel, France and others have developed or are developing DU-containing weapon systems for their inventories. Additionally, DU munitions are sold in the world arms market.Ý

The Institute's findings presented below address Congress' four areas of concern:

• The battlefield is contaminated with many dangerous things. The impact of DU contamination on the battlefield is not well defined. Relative to many of the other hazards, such as unexploded ordnance, the hazards associated with DU contamination are probably small; however, additional environmental modeling and data are needed to support this judgment.

• DU remediation technologies involve one or more of the following: excavation and earth moving, physical separation, chemical separation, and in-place stabilization. The Army will continue to identify and evaluate alternative remediation technologies by comparing the cost and effectiveness. From this analysis, the Army will seek effective, less expensive DU remediation technologies.

• There are no technologies available that can significantly change the inherent chemical and radiological toxicity of DU.

• Range management and DU recovery systems have been implemented and are being improved Models to better describe the environmental fate and effect of DU are being developed. DU migration on test ranges in the United States has been minimal because the soil and water conditions on those ranges tend to prevent formation of soluble DU.

Having completed an exhaustive review of weapon systems containing DU, AEPI concludes that the Army has done an excellent job attending to the environmental and health impacts of these systems. The conclusions contained herein describe additional efforts to attain an even higher level of health and environmental security relative to DU. In many cases the Army has already taken action to implement these initiatives. AEPI believes these candidate efforts will further enhance an already well-reasoned program.

Major conclusions are grouped into several categories relating to their effects on health and the environment, peacetime production and testing, and battlefield use.

General

Establish DU Management Office.

Designate a single office, independent of DU systems development or user activities, to manage and control DU health, environmental and regulatory issues within the Army or DoD.

An independent organization overseeing DU use in the Army could improve the coordination between acquisition, use, demilitarization and remediation activities. This DU management office, functioning as the principal expert, would ensure compliance with applicable laws and regulations and would design, coordinate and evaluate health and environmental research programs.

If this DU office consolidated the Army's current 14 Nuclear Regulatory Commission, non-medical DU systems licenses into a single license, the Army would benefit significantly. A single, standardized license administrated by this centralized DU management and research authority would alleviate present monitoring, equipment and operational inconsistencies between operating locations.

Revise Army Regulations.

The Army should revise its regulations and policy documents to explicitly link the acquisition, use, safety, disposal, demilitarization and environmental management of DU. This could serve as a model for a DoD-wide system.

When taken individually, the current regulations and policy documents adequately express the environmental, system safety and health hazard assessment issues associated with a weapon system during specific phases of its life cycle. What appears to be lacking in the regulations, however, is an explicit cross-reference between the policies of each regulation. With an adequate cross-reference available, those responsible for acquisition would know about the details expected in the environmental regulations and would become familiar with aspects of the ultimate demilitarization and disposal of the system. DU license holders and specific sites using or storing DU-containing systems would be aware of NEPA requirements relative to DU. Demilitarization and disposal experts would learn what to expect after receiving an obsolete system containing DU.

Analyze Life Cycle Costs.

The Army should determine the full life cycle cost of DU weapon systems. This analysis must take into account not only production costs, but also demilitarization, disposal and recycling costs; facility decontamination costs; test range remediation costs; battlefield cleanup costs; and long-term health and environmental costs.

Test Ranges and Battlefields

Expand Training.

The Army should continue to improve training programs for the wide variety of soldiers and support personnel who may come into contact with DU or DU-contaminated equipment. At a minimum, the Army must include armor, infantry, engineer, ordnance, transportation and medical personnel in this training.

In response to the GAO-documented need for additional training, the Army has initiated actions to develop the training programs mentioned.

Assess Medical Surveillance.

To manage any potential health impacts from the use of DU weapon systems, the Army should:

• Develop a screening protocol and treatment criteria to assess veterans who may have been exposed to battlefield DU.

• Review its standard field medical procedures to ensure they are adequate to treat battle wounds contaminated with DU. Develop a standard DU decontamination medical procedure. Train medical personnel to manage DU health risks.

• Initiate research on the long-term health effects of implanted DU fragments. Develop models to estimate the radiation and toxicological consequences of DU internalized as a result of contamination or embedded fragments.

• Continue to identify personnel who were involved in DU friendly fire incidents, but did not receive injuries. The Army should attempt to identify soldiers whose duties required them to enter DU-impacted Iraqi vehicles. This will ensure that they receive health care monitoring and treatment, and it can provide valuable health data on the potential for inhaling DU-containing aerosols.

• Continue to characterize the magnitude of DU contamination of gun tubes and equipment used to ventilate the gun tube after firing. Determine the potential for crew compartment contamination from gun bore gases or flashback incidents.

• Continue to investigate equipment modifications and procedures to minimize crew exposure to both chemical and radiological hazards from DU.

To establish appropriate policy concerning DU, the Army should:

• Continue to maximize recovery of DU penetrators at test ranges and require that high explosive test ranges be separated from new DU test ranges so that future DU recovery efforts will not be complicated by the current problem of unexploded ordnance. Emphasis should be placed on maximizing DU recycling within the Army system.

• Fund recovery, recycling and waste disposal programs adequately, and plan for site remediation on Army installations consistent with land use goals. The environmental impacts of remedial action options will be a consideration in determining future land use.

• Fund development of waste disposal options, including volume reduction, waste minimization, waste form modification and new disposal facility development.

• Review and, if necessary, revise environmental documentation on DU weapon systems and NRC licenses to ensure completeness, accuracy and currency. Army regulations implementing NEPA require program managers to generate and maintain life cycle environmental documentation for weapon systems. Army policy also requires NEPA documentation for all NRC license applications.

• Continue to participate aggressively in low-level waste compacts, at both state and regional levels. Low-Level Radioactive Waste Policy Act and Nuclear Regulatory Commission regulations control DU disposal. The Act provides language for states to create regional compacts for the purpose of low-level radioactive waste disposal. Limitations on the amount of low-level waste that can be sent to the few current waste sites could result in test sites being forced to retain this material and, as such retention approaches NRC license limitations, could limit the Army's ability to conduct further testing.

• The Army should continue to evaluate the environmental fate and effect of DU on U.S. test ranges. A better understanding of DU contamination at test ranges could produce data and models transferable to other sites, including battlefields.

• Upon appropriate request, help host countries to locate and characterize sites used by tank crews for practice with their main guns using DU ammunition. Because the majority of DU ammunition expended in Desert Storm was used in practice, these firing sites are ideal candidates for both characterizing and verifying theories on DU's environmental behavior. Evaluating the DU forms present and their transport characteristics under the different soil/climate conditions of Southwest Asia could also provide valuable information for calibrating a risk/cost model. Fire and battle sites also will provide valuable data to support the development of accurate environmental models. Characterizing these sites will provide conclusive evidence of the environmental impact of DU on the battlefield.

• Consider methods, including salvage, maintenance and repair methods, to better characterize DU contamination in battlefield areas.
• Use the data and models being developed to determine the risks and costs associated with remediating areas contaminated by DU. Accurate costs to remediate test ranges and battle sites may be used in the life cycle cost analyses for DU-containing weapon systems.

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The Army Environmental Policy Institute wrote this summary report, as directed by the Deputy Assistant Secretary of the Army (Environment, Safety and Occupational Health) in response to Senate Appropriations Committee Report Number 102-408. This summary report is based on a detailed technical report, Health and Environmental Consequences of Depleted Uranium Use by the U.S. Army, that is available upon written request. Forward requests to:

Office of the Assistant Secretary of the Army for Installations, Logistics and Environment
The Pentagon, Room 2E614
Washington, DC 20310

The Army Environmental Policy Institute (AEPl) prepared this summary report under the direction of Mr. Lewis D. Walker, Deputy Assistant Secretary of the Army for environment, Safety and Occupational Health, OASA (IL&E). This document was published in accordance with format guidance from OASA (IL&E).

The Institute's mission is to assist the Army Secretariat in developing proactive policies and strategies to address environmental issues that may have significant future impacts on the Army.

A team of experts, directed by Stephen P. Shelton, Ph.D., P.E., D.E.E., Interim Director, AEPI, coordinated all efforts to prepare this report and the supporting technical report. The American Restoration Corporation (ARC) of Arlington, Virginia, extracted information from the technical report and revised it to prepare the original version of this document. Lamb Associates, Inc. of Albuquerque, New Mexico, provided fundamental support throughout this project.

Principal authors and members of the technical team include: LTC Eric G. Daxon, Ph.D., Department Chair, Armed Forces Radiobiology Research Institute; Robert T. Kowalski, General Engineer, Picatinny Arsenal; David O. Lindsay, COL, U.S. Army Corps of Engineers (Retired), Consultant; George P. O'Brien, Project Engineer, Picatinny Arsenal; Tanya Palmateer-Oxenberg, Health Physicist, U.S. Army Test and Evaluation Command; Jane E. Rael, Ph.D. Candidate, Department of Civil Engineering, University of New Mexico; Stephen P. Shelton, Ph.D., P.E., D.E.E., Professor of Civil Engineering, University of New Mexico, and Interim Director, AEPI; Donald G. Silva, P.E., D.E.E., LTC USAF Biomedical Science Corps (Retired), Senior Associate, Lamb Associates, Inc.; Ronald A. Smith, Program Manager, Lamb Associates, Inc.; Lesca Strickland, Esquire, Life Systems, Inc.; Bruce M. Thomson, Ph.D., P.E., Professor of Civil Engineering, University of New Mexico; Francisco Torres Tomei, Ph.D., Associate Professor of Civil Engineering, University of New Mexico, and Fellow, AEPI.

COL Randall Morin, USA, provided staff support from Mr. Walker's office. Recognition is also due to BG Gerald C. Brown, USA, Director, Environmental Programs; CAPT Robert L. Bumgarner, USN, Director, Armed Forces Radiobiology Research Institute; Richard W. Fliszar, USA, Picatinny Arsenal; LTC J. Christopher Johnson, USA, Headquarters, U.S. Army Materiel Command; and COL Peter H. Meyers, USA, Radiological Hygiene Consultant, Office of the Surgeon General.

Within the Army the following provided review, comments and suggestions: Office of the Deputy Chief of Staff for Operations and Plans, Office of the Deputy Chief of Staff for Logistics, Office of the Surgeon General, Office of the General Counsel, Office of the Chief of Public Affairs, Office of the Chief of Legislative Liaison, Office of the Director of Environmental Programs, Office of the Director of Army Safety, and Office of the Assistant Secretary of the Army for Research, Development and Acquisition. Additionally, more than 200 Army personnel, involved in some way with depleted uranium, deserve thanks for their contributions to this report.

Beyond the Army, review, comments, and suggestions were provided by the Office of the Deputy Under Secretary of Defense (Environmental Security), the Armed Forces Radiobiology Research Institute, the Office of the Deputy Assistant Secretary of the Air Force (Environment, Safety and Occupational Health), and the Office of the Deputy Assistant Secretary of the Navy (Installations and Logistics). Both this summary report and the technical document were also externally reviewed at three universities.

Army Environmental Policy Institute
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