TAB L - Research Report Summaries
This tab provides a summary of some of the major research efforts regarding the military use of depleted uranium. While this listing is not intended to be all-inclusive, it does provide a sense of the depth and breadth of research conducted to date. The studies listed below are summarized on the pages to follow.
Study Number |
Description |
1 | Hanson, Wayne C. Ecological Considerations of Depleted Uranium Munitions, LA-5559. Los Alamos, NM: Los Alamos Scientific Laboratory, June 1974. |
2 | Environmental Assessment - Depleted Uranium (DU) Armor Penetrating Munitions for the GAU-8 Automatic Cannon, Development and Operational Test and Evaluation, AF/SGPA, April 1975. |
3 | Elder, J.C., M.I. Tillery, and H.J. Ettinger. Hazard Classification Test of GAU-8 Ammunition by Bonfire Cookoff with Limited Air Sampling, LA-6210-MS, Informal Report. Los Alamos, NM: Los Alamos Scientific Laboratory of the University of California, February 1976. |
4 | Prado, Captain Karl L. External Radiation Hazard Evaluation of GAU-8 API Munitions, TR 78-106. Brooks Air Force Base, TX: USAF Occupational and Environmental Health Laboratory, 1978. |
5 | Bartlett, W.T., R.L. Gilchrist, G.W.R. Endres, and J.L. Baer. Radiation Characterization, and Exposure Rate Measurements From Cartridge, 105-mm, APFSDS-T, XM774, PNL-2947. Richland, WA: Battelle Pacific Northwest Laboratory, November 1979. |
6 | Gilchrist, R.L., J.A. Glissmyer, and J. Mishima. Characterization of Airborne Uranium From Test Firings of XM774 Ammunition, PNL-2944. Richland, WA, Battelle Pacific Northwest Laboratory, November 1979. |
7 | Davitt, Richard P. A Comparison of the Advantages and Disadvantages of Depleted Uranium and Tungsten Alloy As Penetrator Materials, Tank Ammo Section Report No. 107. Dover, NJ: US Army Armament Research and Development Command, June 1980. |
8 | Ensminger, Daniel A. and S.A. Bucci. Procedures to Calculate Radiological and Toxicological Exposures From Airborne Release of Depleted Uranium, TR-3135-1. Reading, MA: The Analytic Sciences Corporation, October 1980. |
9 | Elder, J.C. and M.C. Tinkle. Oxidation of Depleted Uranium Penetrators and Aerosol Dispersal at High Temperatures, LA-8610-MS. Los Alamos, NM: Los Alamos Scientific Laboratory of the University of California, December 1980. |
10 | Chambers, Dennis R., Richard A. Markland, Michael K Clary, and Roy L. Bowman. Aerosolization Characteristics of Hard Impact Testing of Depleted Uranium Penetrators, Technical Report ARBRL-TR-02435. Aberdeen Proving Ground, MD: US Army Armament Research and Development Command, Ballistic Research Laboratory, October 1982. |
11 | Hooker, C.D., D.E. Hadlock, J. Mishima, and R.L. Gilchrist. Hazard Classification Test of the Cartridge, 120 mm, APFSDS-T, XM829, PNL-4459. Richland, WA: Battelle Pacific Northwest Laboratory, November 1983. |
12 | Mishima, J., M.A. Parkhurst, R.L. Scherpels, and D.E. Hadlock. Potential Behavior of Depleted Uranium Penetrators under Shipping and Bulk Storage Accident Conditions, PNL-5415. Richland, WA: Battelle Pacific Northwest Laboratory, March 1985. |
13 | Wilsey, Edward F. and Ernest W. Boore, Draft Report: Radiation Measurement of an M1A1 Tank Loaded with 120-MM M829 Ammunition. Aberdeen Proving Ground, MD: US Army Ballistic Research Laboratory, July 1985. |
14 | Magness, C. Reed. Environmental Overview for Depleted Uranium, CRDC-TR-85030. Aberdeen Proving Ground, MD: Chemical Research & Development Center, October 1985. |
15 | Scherpelz, R.I, J. Mishima, L.A. Sigalla, and D.E. Hadlock. Computer Codes for Calculating Doses Resulting From Accidents involving Munitions Containing Depleted Uranium, PNL-5723. Richland, WA: Battelle Pacific Northwest Laboratory, March 1986. |
16 | Haggard, D.L., C.D. Hooker, M.A. Parkhurst, L.A. Sigalla, W.M. Herrington, J. Mishima, R.I. Scherpelz, and D.E. Hadlock. Hazard Classification Test of the 120-MM, APFSDS-T, M829 Cartridge: Metal Shipping Container, PNL-5928. Richland, WA: Battelle Pacific Northwest Laboratory, July 1986. |
17 | Hooker, C.D. and D.E. Hadlock. Radiological Assessment Classification Test of the 120-MM, APFSDS-T, M829 Cartridge: Metal Shipping Container, PNL-5927. Richland, WA: Battelle Pacific Northwest Laboratory, July 1986. |
18 | Life Cycle Environmental Assessment For the Cartridge, 120MM: APFSDS-T, XM829. Picatinny Arsenal, NJ: US Army Armament Research, Development and Engineering Center, Close Combat Armament Center, December 12, 1988. |
19 | Parkhurst, M.A. and K.L. Sodat. Radiological Assessment of the 105-MM, APFSDS-T, XM900E1 Cartridge, PNL-6896. Richland, WA: Battelle Pacific Northwest Laboratory, May 1989. |
20 | Wilsey, Edward F. and E.W. Bloore. M774 Cartridges Impacting Armor-Bustle Targets: Depleted Uranium Airborne and Fallout Material, BRL-MR-3760. Aberdeen Proving Ground, MD: Ballistic Research Laboratory, May 1989. |
21 | Erikson, R.L., C.J. Hostetler, J.R. Divine, and K.R. Price. Environmental Behavior of Uranium Derived From Depleted Uranium Alloy Penetrators, PNL-5927. Richland, WA: Battelle Pacific Northwest Laboratory, June 1989. |
22 | Fliszar, Richard W., Edward F. Wilsey, and Ernest W. Bloore. Radiological Contamination from Impacted Abrams Heavy Armor, Technical Report BRL-TR-3068. Aberdeen Proving Ground, MD: Ballistic Research Laboratory, December 1989. |
23 | Hadlock, D.E. and M.A. Parkhurst. Radiological Assessment of the 25-MM, APFSDS-T XM919 Cartridge, PNL-7228. Richland, WA: Battelle Pacific Northwest Laboratory, March 1990. |
24 | M.A. Parkhurst, J. Mishima, D.E. Hadlock, and S.J. Jette. Hazard Classification and Airborne Dispersion Characteristics of the 25-MM, APFSDS-T XM919 Cartridge, PNL-7232. Richland, WA: Battelle Pacific Northwest Laboratory, April 1990. |
25 | Kinetic Energy Penetrator Long Term Strategy Study (Abridged), Final Report. Picatinny Arsenal, NJ: US Army Production Base Modernization Activity, July 24, 1990. |
26 | Jette, S.J., J. Mishima, and D.E. Haddock. Aerosolization of M829A1 and XM900E1 Rounds Fired Against Hard Targets, PNL-7452. Richland, WA: Battelle Pacific Northwest Laboratory, August 1990. |
27 28 |
Munson, L.H., J. Mishima,
M.A. Parkhurst, and M.H. Smith. Radiological Hazards
Following a Tank Hit with Large - Caliber DU Munitions,
Draft Letter Report. Richland, WA: Battelle Pacific
Northwest Laboratory, October 9, 1990. Memorandum for SMCAR-CCH-V from SMCAR, Radiological Hazards in the Immediate Areas of a Tank Fire and/or Battle Damaged Tank Involving Depleted Uranium, Letter Report, Picatinny Arsenal, NJ, December 4, 1990. |
29 | Mishima, J., D.E. Hadlock, and M.A. Parkhurst. Radiological Assessment of the 105-MM, APFSDS-T, XM900E1 Cartridge by Analogy to Previous Test Results, PNL-7764. Richland, WA: Battelle Pacific Northwest Laboratory, July 1991. |
30 | Parkhurst, M.A. Radiological Assessment of M1 and M60A3 Tanks uploaded with M900 Cartridges. PNL-7767. Richland, WA: Battelle Pacific Northwest National Laboratory, July 1991. |
31 | Life Cycle Environmental Assessment for the Cartridge, 105MM: APFSDS-T, XM900E1. Picatinny Arsenal, NJ: US Army Armament Research, Development and Engineering Center, Close Combat Armament Center, August 21, 1991. |
32 | Life Cycle Environmental Assessment For the Cartridge, 120MM: APFSDS-T, XM829A2. Picatinny Arsenal, NJ: US Army Production Base Modernization Activity, February 2, 1994. |
33 | Parkhurst, M.A. and R.I. Scherpelz. Dosimetry of Large Caliber Cartridges: Updated Dose Rate Calculations, PNL-8983. Richland, WA: Battelle Pacific Northwest Laboratory, Reissued, June 1994. |
34 | Parkhurst, M.A., G.W.R. Endres, and L.H. Munson. Evaluation of Depleted Uranium Contamination in Gun Tubes, PNL-10352. Richland, WA: Battelle Pacific Northwest Laboratory, January 1995. |
35 | Parkhurst, M.A., J.R. Johnson, J. Mishima, and J.L. Pierce. Evaluation of DU Aerosol Data: Its Adequacy for Inhalation Modeling, PNL-10903. Richland, WA: Battelle Pacific Northwest Laboratory, December 1995. |
Report Number 1
Hanson, Wayne C. Ecological Considerations of Depleted Uranium Munitions, LA-5559. Los Alamos, NM: Los Alamos Scientific Laboratory, June 1974.
This report concluded that the major ecological hazard from expended DU munitions would be chemical toxicity rather than radiation. Because DU munitions are composed of alloys, the mobility of the DU is substantially decreased compared to uranium. However, the report stated that the chemical toxicity of expended DU to terrestrial ecosystems could not be ignored and must be seriously considered.
Report Number 2
Environmental Assessment, Depleted Uranium (DU) Armor Penetrating Munitions for the GAU-8 Automatic Cannon, Development and Operational Test and Evaluation, AF/SGPA, April 1975.
This was the Environmental Assessment for the US Air Forces GAU-8 Program. It covered the manufacturing, transportation, storage, use and disposal of GAU-8 ammunition and resulted in a finding of no significant environmental impact.
Report Number 3
Elder, J.C., M.I. Tillery, and H.J. Ettinger. Hazard Classification Test of GAU-8 Ammunition by Bonfire Cookoff with Limited Air Sampling, LA-6210-MS, Informal Report. Los Alamos, NM: Los Alamos Scientific Laboratory of the University of California, February 1976.
On August 26, 1975, the Los Alamos Lab (under contract to the US Air Force Armament Laboratory, Eglin AFB, FL) tested the GAU-8 ammunition to establish its hazard classification. The new armor-piercing version of the GAU-8 (30-mm) contained a DU core. In addition to "fragment pattern scoring" (the usual objective of a bonfire cookoff test), testers sampled the air to evaluate the potential for airborne DU. One hundred and eighty live GAU-8 rounds were set off in the bonfire cook-off. The test plan did not include the measurement of aerosol size characteristics and mass concentrations.
Analysis of the air sampling data concluded nothing beyond the obvious fact that DU aerosol was released. All but one of the 180 rounds remained within 400 feet of the bonfire. The exception was a shell base. The DU penetrators lost a good deal of mass in the bonfireabout 30% of the penetrators lost visually detectable amounts of DU. The remaining rounds escaped the high temperatures that normally turn DU into aerosol and ash. As the report notes, "Almost total dispersion of several penetrators to aerosol and ash illustrated the probable fate of any penetrator remaining in a high temperature region." In other words, in fires, the potential for DU aerosol dispersion is greater than in other scenarios.
Report Number 4
Prado, Captain Karl L. External Radiation Hazard Evaluation of GAU-8 API Munitions, TR 78-106. Brooks Air Force Base, TX: USAF Occupational and Environmental Health Laboratory, 1978.
The study concluded that the standards for protection against radiation (10CFR20.105) were met during typical field conditions, provided that: "(1) occupancy of any area 100 cm from any accessible surface of stored CNU-309/E containers by non-occupationally exposed personnel does not exceed a total of 1,000 hours per year, and that (2) the PGU-14/B cartridge is in a case when handled (If the cartridge is handled directly, the total contact time with the projectile surface should not exceed 180 hours per calendar quarter)."
Report Number 5
Bartlett, W.T., R.L. Gilchrist, G.W.R. Endres, and J.L. Baer. Radiation Characterization, and Exposure Rate Measurements From Cartridge, 105-mm, APFSDS-T, XM774, PNL-2947. Richland, WA: Battelle Pacific Northwest Laboratory, November 1979.
This was one of three studies recommended by the Joint Technical Coordinating Group for Munitions Effectiveness Working Group on Depleted Uranium Munitions in their initial 1974 environmental assessment of DU. This study focused on the health physics problems associated with the assembly, storage, and use of the 105 mm, APFSDS-T, XM774 ammunition. The conclusion of the report was that the "radiation levels associated with the XM774 ammunition are extremely low. The photon emissions measured did not exceed a maximum whole-body or critical organ exposure of 0.26 mR/hr. Even if personnel were exposed for long periods to the highest levels of radiation measured, it is doubtful that their exposure would reach 25% of the maximum permissible occupational dose listed in Title 10 of the Code of Federal Regulations, Part 20."
Report Number 6
Gilchrist, R.L., J.A. Glissmyer, and J. Mishima. Characterization of Airborne Uranium From Test Firings of XM774 Ammunition, PNL-2944. Richland, WA, Battelle Pacific Northwest Laboratory, November 1979.
This was the last of three studies recommended by the Joint Technical Coordinating Group for Munitions Effectiveness (JTCG/ME) in the late 1970s. The purpose of this particular test was to gather data necessary to evaluate the potential human health exposure to airborne DU. (The other two studies were: "Radiological and Toxicological Assessment of an External Heat (Burn) Test of the 105 mm Cartridge, APFSDS-T, XM774" and "Radiation Dose Rate Measurements Associated with the Use and Storage of XM774 Ammunition.") Data collected during this test included the following:
The study included extensive assessment of total and respirable DU levels above the targets and at downwind locations, fallout and fragment deposition around the target, and high-speed movies of the smoke generated by the penetrator impact to estimate the cloud volume. Although technical problems were encountered during the test with filter overload, etc., the following conclusions were drawn:
Numerous problems were encountered during the sampling for total particulates, which contributed to the conclusion that the average fraction of the penetrator being aerosolized was 70%. These problems included:
Despite the technical problems encountered during the test, 70% is frequently cited as the average level of penetrator aerosolized during hard impact.
Report Number 7
Davitt, Richard P. A Comparison of the Advantages and Disadvantages of Depleted Uranium and Tungsten Alloy As Penetrator Materials, Tank Ammo Section Report No. 107. Dover, NJ: US Army Armament Research and Development Command, June 1980.
This report provides an excellent history of the logic behind the Armys decision to use DU as a kinetic energy, armored-piercing munition. The final selection of DU over Tungsten was based on a combination of reasons, including the lower initial cost of the penetrator itself and its overall improved performance. DU and Tungsten were rated even for "producibility." Tungsten had the advantage for safety, environmental concerns, and deployment.
Report Number 8
Ensminger, Daniel A. and S.A. Bucci. Procedures to Calculate Radiological and Toxicological Exposures From Airborne Release of Depleted Uranium, TR-3135-1. Reading, MA: The Analytic Sciences Corporation, October 1980.
This report provided a description of the models for assessing radiological and toxicological exposures from airborne dispersions of DU under given release conditionsparticularly APFSDS-T (Armor-Piercing, Fin-Stabilized, Discarding Sabot-Tracered) XM774 and M735A1 rounds.
Report Number 9
Elder, J.C. and M.C. Tinkle. Oxidation of Depleted Uranium Penetrators and Aerosol Dispersal at High Temperatures, LA-8610-MS. Los Alamos, NM: Los Alamos Scientific Laboratory of the University of California, December 1980.
This was an early test to evaluate the consequences of exposing DU penetrators to a variety of thermal conditions ranging from 500� C to 1,000� C in different atmospheres for 2 to 4 hours. The general conclusions of these tests were:
Report Number 10
Chambers, Dennis R., Richard A. Markland, Michael K Clary, and Roy L. Bowman. Aerosolization Characteristics of Hard Impact Testing of Depleted Uranium Penetrators, Technical Report ARBRL-TR-02435. Aberdeen Proving Ground, MD: US Army Armament Research and Development Command, Ballistic Research Laboratory, October 1982.
This is the early documentation required by the NRC to support indoor, confined testing of 105 and 120mm kinetic energy DU rounds. NRC initially approved the test firing of 10 rounds to verify the integrity of the test facility; then it approved the firing of 20 DU penetrators to characterize the aerosol generated by a penetrator impact with an armor target. The study contradicted a previous study by Battelle for the XM774, which indicated that up to 70% of the DU penetrator was aerosolized upon impact. During this study, approximately 3% of the penetrator was aerosolized 2-3 minutes after impact, and accounting for error, it was highly unlikely that more than 10% was aerosolized. The test data was consistent with previous test data for small caliber ammunition. For the aerosolized particulates, the mass mean diameter was 1.6 microns and approximately 70% was less than 7 microns, which is considered the upper range of respirable particulates for DU. The study raised many questions concerning the nature of aerosols generated by hard impact testing of DU penetrators.
Report Number 11
Hooker, C.D., D.E. Hadlock, J. Mishima, and R.L. Gilchrist. Hazard Classification Test of the Cartridge, 120 mm, APFSDS-T, XM829, PNL-4459. Richland, WA: Battelle Pacific Northwest Laboratory, November 1983.
The purpose of this test was to determine the behavior of the XM829 cartridge when subjected to (1) detonation of an adjacent XM829 cartridge, and (2) a sustained hot fire. The test concluded that detonating a XM829 cartridge in one container would not cause the immediate detonation of XM829 cartridges in adjacent cartridges. But if a fire starts and continues to burn, adjacent cartridges may ignite, scattering debris up to 40 feet. A mass analysis for the two tests conducted under this project indicated that at least 80% of the cartridges mass was recovered in the 1982 test and 100% was recovered in the 1983 test. No DU contamination was detected in samples from the sand taken from ground zero. An analysis of the filters from 7 high volume air samplers also indicated that the airborne level of DU remained at natural background levels. The report noted that "great care was taken during this time to prevent the residue from being scattered by winds and that under different conditions these values could vary." An analysis of the respirator canisters also revealed no measurable levels of DU.
Report Number 12
Mishima, J., M.A. Parkhurst, R.L. Scherpels, and D.E. Hadlock. Potential Behavior of Depleted Uranium Penetrators under Shipping and Bulk Storage Accident Conditions, PNL-5415. Richland, WA: Battelle Pacific Northwest Laboratory, March 1985.
The purpose of this test was to characterize the particle size, morphology, and lung solubility of DU oxide samples from 120 mm M829 DU rounds exposed to an external heat test and to conduct a literature search on "uranium oxidation rates, the characteristics of oxides generated during the fire, the airborne release as a result of the fire, and the radiological/toxicological hazards from inhaled uranium oxides."
The test results indicated that a maximum of 0.6% by weight of the DU oxide generated was in the respirable range (i.e., less than 10 m m Aerodynamic Equivalent Diameter) and that the respirable fraction of the oxide was insoluble (i.e., 96.5% had not dissolved within 60 days). The study concluded that DU oxides formed during burning should be classified as insoluble (Class Y-dissolution half-times in the lung of more that 100 days).
Report Number 13
Wilsey, Edward F. and Ernest W. Boore. Draft Report: Radiation Measurement of an M1A1 Tank Loaded with 120-MM M829 Ammunition. Aberdeen Proving Ground, MD: US Army Ballistic Research Laboratory, undated.
This work was supported by the Project Manager, M1A1 Abrams Tank System, US Army Tank and Automotive Command. The tank was loaded with forty M829 120mm rounds to evaluate crew radiation exposure levels. "Preliminary results of the radiation exposures to M1A1 tank crews were well within the Nuclear Regulatory Guidelines for the general population and there was no undue radiation hazard when the tank was fully loaded with M829 rounds."
Report Number 14
Magness, C. Reed. Environmental Overview for Depleted Uranium, CRDC-TR-85030, Aberdeen Proving Ground, MD, Chemical Research & Development Center, October 1985.
This is an excellent environmental overview of DUits relation to natural uranium, its applications (both commercial and military), and its long-term effects on man and the environment. The Army conducted this study to fulfill the relevant background information for Army documentation requirements as detailed in Army Regulation (AR) 200-2.
Report Number 15
Scherpelz, R.I., J. Mishima, L.A. Sigalla, and D.E. Hadlock. Computer Codes for Calculating Doses Resulting From Accidents involving Munitions Containing Depleted Uranium, PNL-5723. Richland, WA: Battelle Pacific Northwest Laboratory, March 1986.
The report described the Armys computer modeling to determine whether or not an exclusion zone should be imposed around an accident site, where a boundary should be located, and whether the potential effects farther downwind would be significant or trivial based the characteristics of the incident, the actual munitions involved, and the packaging of the munitions.
Report Number 16
Haggard, D.L., C.D. Hooker, M.A. Parkhurst, L.A. Sigalla, W.M. Herrington, J. Mishima, R.I. Scherpelz, and D.E. Hadlock. Hazard Classification Test of the 120-MM, APFSDS-T, M829 Cartridge: Metal Shipping Container, PNL-5928. Richland, WA: Battelle Pacific Northwest Laboratory, July 1986.
This was a follow-up test to the Hazard Classification Test summarized in PNL 4459 (Report Number 11 above), which was conducted with a wooden shipping container. This follow-up test was conducted to evaluate a new PA-116 metal shipping container. The results:
The test also revealed these radiological aspects:
The study concluded that, "the minute quantity of oxide that was of respirable size and the calm winds limited the downwind disposal and posed no biological hazard to cleanup crews or others in the area."
Report Number 17
Hooker, C.D. and D.E. Hadlock. Radiological Assessment Classification Test of the 120-MM, APFSDS-T, M829 Cartridge: Metal Shipping Container, PNL-5927. Richland, WA: Battelle Pacific Northwest Laboratory, July 1986.
This was the follow-up study to a 1983 study evaluating potential health problems when the M829 cartridge is shipped and stored in wooden containers. This follow-up assessment was necessary to evaluate radiation levels when the M829 cartridge is packaged in a metallic container. Results of the study indicate the following:
Report Number 18
Life Cycle Environmental Assessment For the Cartridge, 120MM: APFSDS-T, XM829. Picatinny Arsenal, NJ: US Army Armament Research, Development and Engineering Center, Close Combat Armament Center, December 12, 1988.
This was the initial Environmental Assessment (EA) for the M829 armor piercing round. The M829 replaced the XM827 (the American analog of the German DM 13), which was the initial APFSDS-T round. The program included the development and testing of four rounds: Target Practice (M831), High Explosive (M830), Armor Piercing (XM827), and Target Practice (M865). The EA incorporates all of the previous supporting studies on the M829 round (e.g., the radiological and hazard classification of the metal and wooden shipping containers). The conclusion of the EA was a "Finding of No Significant Impact" for the design, production, test and evaluation, deployment, and demilitarization of the M829.
Report Number 19
Parkhurst, M.A. and K.L. Sodat. Radiological Assessment of the 105-MM, APFSDS-T, XM900E1 Cartridge, PNL-6896. Richland, WA: Battelle Pacific Northwest Laboratory, May 1989.
In this study the XM900E1 round was packaged in the PA-117 steel container. The conclusions of the report are as follows:
Report Number 20
Wilsey, Edward F. and E.W. Bloore. M774 Cartridges Impacting Armor-Bustle Targets: Depleted Uranium Airborne and Fallout Material, BRL-MR-3760. Aberdeen Proving Ground, MD: Ballistic Research Laboratory, May 1989.
This study was one of several conducted on the M774 ammunition (105mm). It addresses only one objectivethe documentation of the amount of DU aerosol and fallout around and downwind of the armor-bustle target. "Very little of the depleted uranium of the M774 penetrator left the immediate target area as an aerosol." The highest valueregardless of the wind conditionswas so low that over 1,400 such tests would have to be fired in a week before tolerance limits would begin to be reached. While the threshold limit value was exceeded when the cloud passed over the samplers, the time-weighted-average exposure for a 40-hour workweek was only 0.07% of the occupational Threshold Limit Value.
Report Number 21
Erikson, R.L., C.J. Hostetler, J.R. Divine, and K.R. Price. Environmental Behavior of Uranium Derived From Depleted Uranium Alloy Penetrators, PNL-2761. Richland, WA: Battelle Pacific Northwest Laboratory, June 1989.
This report covers some of the factors affecting the conversion of DU metal to oxide, the subsequent influences on the leaching and mobility of uranium through surface water and groundwater pathways, and the absorption of uranium by growing plants. Although the report is not directly related to the Gulf War, it demonstrates the Armys efforts to understand the environmental fate of uranium.
Report Number 22
Fliszar, Richard W., Edward F. Wilsey, and Ernest W. Bloore. Radiological Contamination from Impacted Abrams Heavy Armor, Technical Report BRL-TR-3068. Aberdeen Proving Ground, MD: Ballistic Research Laboratory, December 1989.
The objective of this test was to evaluate DU aerosol levels generated inside and outside a heavy armor Abrams tank (i.e., DU armor) impacted by various types of rounds. The test also evaluated particle size distributions of DU puffs generated by the impact near the point of impact and within 100 meters from the tank, resuspension levels within 100 meters of the tank, and DU contamination in air from a burning M1A1 tank with heavy armor after being hit.
The following types of rounds were used in the seven tests:
In evaluating the data from the test, it is important to recognize the difference between the aerosols typically generated as puffs from impact and aerosols generated from a fire plume involving DU penetrators. Numerous tests have demonstrated that "DU penetrators when burned in a fire for hazard classification, have formed highly insoluble DU oxides, at least in the respirable size range."
The following permissible exposure levels of uranium in the air and soil were extracted from Table 5 of the report:
Medium | Condition | Less than - | Source |
Air | Non-occupational, Soluble U-238 |
3 x 10-12
m Ci/ml (or 192 m g/day) |
10CFR20, App
B Table 2, Column 1 |
Occupational, Soluble U-238 |
7 x 10-12 m Ci/ml | Same, Table 1, Column 1 |
|
Soil | Unrestricted | 35 pCi/gram 97 m g/gram |
Federal
Register, 46, 205, pp. 5261 to 5263, (1981) |
Vehicles | Removable contamination for uncontrolled use | Alpha: 450dpm/100 cm2 Beta: 550dpm/100cm2 |
(AMC) DARCOM 385-1.1-78 |
Based on the test data, exposures from passing clouds are insignificant beyond 100 meters. The maximum estimated intake at distances greater than 100 meters was 0.82 micrograms of DU. The study noted that it would only take four minutes to reach the airborne limit for the general public, but the passing cloud from each test was present for only a few seconds at a given location. Within 100 meters, but outside the cloud path, air sample results were also insignificant. This included air samplers within 5 to 10 meters of the target. Air sample results in the cloud path varied with the highest level being recorded at a distance of 10 meters from the target (280 microgramsan acute exposure). There was little additional intake after the puff passed by. Air sampling results for test #6 (a Hellfire equivalent caused a fire that consumed the vehicle) were still within the intake limit even though the air samplers were also exposed to the plume of the fire.
Cascade impactor data for puff of smoke generated at impact revealed that the particles within the cloud were primarily respirable particles (ranging from 76% at the point of impact to 85% just outside the cloud path and 79% along the cloud path). Results of the resuspension air samplers at a distance of 10 to 100 meters from the target revealed that at least for this test, resuspension was not a problem. The highest level recorded was 1.7 x 10-14 microcuries/ml which was well within the limit for airborne uranium.
A personal sampler was worn in the breathing zone by a member of the initial reentry team to evaluate resuspension at the test pad and while climbing inside the crew compartment. All of the resuspension results were within acceptable limits except in Test 6B. For Test 6B, reentry occurred following the fire and the Test 6B sample was collected primarily from inside the crew compartment. The report indicated that a penetrator might have been ejected from one of the storage compartments into the crew compartment and then completely oxidized during the test. Even so, the report cited that the airborne concentration was just above the limit for soluble U-238 and that the limit for insoluble U-238 (5 x 10-12 microcuries/ml) was probably appropriate. Based on the insoluble U-238 criteria, all resuspension data would be within acceptable limits.
Test data for representative welding operations lasting approximately 20 minutes revealed that exposure levels were above the unrestrictive release limits of 3 x 10 -12microcuries/ml of uranium. However, they were never above restricted area limits of 7 x 10-11 microcuries/ml. Local exhaust ventilation was not used for these welding operations and the welding was performed both outside and inside the target, both indoors and outdoors. The report stated that "Even if airborne levels of DU had been above the restricted limit during welding, the welder probably would not have been overexposed. The exposure would be time-weighted to the actual amount of time the welder was working. The usual patchwork took about 20 minutes." However, the welder would still need to wear a respirator under the ALARA guidelines and to protect against other welding hazards such as iron oxide fumes.
For all of the tests, the highest fallout levels occurred on the test pad within 5 to 7 meters of the target. However it was noted that heavy armor material was blown out 76 meters (250 feet) or more from the target after several tests.
Interior air sampling was also taken during the three last impact tests when breakthrough into the crew compartment occurred. Data, though limited, was collected on the first two of those impact events. Data for the last impact was lost because the vehicle caught fire destroying all of the air samplers. During the two impact events in which the penetrators entered through the turret into the main crew area, the air samplers located in the Commander, Gunner and Loader crew positions all shut down during the initial minute following impact. This is probably attributable to either ballistic shock from the impact itself, and/or disruption by the short-lived electromagnetic field, which occurs during armor impact. All of the air samplers placed within the vehicle were small battery powered samplers.
In conducting an assessment of the data it was conservatively assumed that the samplers that shut off did so within the first second after impact. Based on that assumption and knowing the flow rate of the respective samplers, an estimate of intake by an individual was calculated with reference to an inhalation rate of 30 liters per minute (lpm). The maximum mass of DU on a filter in the first breakthrough impact was 3.7 mg DU total dust at the Gunners position. This equated to a projected intake of 26 mg DU total dust for that second in time. In the second breakthrough impact event, the maximum mass of DU measured on a filter was 4.6 mg DU total dust at the Drivers position. This sampler, however, continued to run until turned off during re-entry activities, about 16 minutes after impact. Based on the sampler flow rate and an inhalation rate of 30 lpm, a projected intake to the driver over that 16-minute period would have been 28 mg DU total dust.
Although the filter for the driver collected 4.6 mg of DU over the 16-minute period, the highest filter reading in the main crew compartment during the event was 2.4 mg, presumably collected in a matter of moments before the sampler shut off. This fact suggests that appreciably higher concentrations of DU might have been collected in the main crew compartment, as opposed to that in the driver compartment, had the sampler not shut off.
Based on the circumstances surrounding each of the two impact breakthroughs for which samples inside the vehicle were collected, significantly higher results would have been predicted for the first impact breakthrough. In the first the turret armor impacted had already been hit on two prior occasions, that may have added to the DU residue inside the tank that was resuspended in the crew compartment at impact. In addition, a DU kinetic energy (KE) round was fired into the armor package during this breakthrough event. In contrast, the round fired for the second event was a non-DU KE round, and the DU turret armor package impacted was impacted for the first time. This discrepancy may be explained by the fact that in the first breakthrough event the vehicle's NBC exhaust air filtration exhaust system was running and the Loader's hatch opened upon impact. In the second breakthrough event, the NBC system was off, and none of the vehicle's hatches opened when impact occurred.
Report Number 23
Hadlock, D.E. and M.A. Parkhurst. Radiological Assessment of the 25-MM, APFSDS-T XM919 Cartridge, PNL-7228. Richland, WA: Battelle Pacific Northwest Laboratory, March 1990.
The purpose of the study was to assess the health issues associated with the handling, storage and shipment of 25mm, APFSDS-T, XM919 ammunition for the US Army Bradley M3A1 and the US Marine LAV-25. The DU cartridges for the M919 ammunition are packaged in the Army plastic (M-621) and metal (PA-125) shipping containers and the Marine metal (CNU-405) shipping container. The study evaluated radiation levels for shipping containers in storage configurations within and outside the fighting vehicles. The results are as follows:
Report Number 24
Parkhurst, M.A., J. Mishima, D.E. Hadlock, and S.J. Jette. Hazard Classification and Airborne Dispersion Characteristics of the 25-MM, APFSDS-T XM919 Cartridge, PNL-7232. Richland, WA: Battelle Pacific Northwest Laboratory, April 1990.
Although the 25mm, APFSDS-T M919 cartridge was not used during Desert Shield/Desert Storm, a summary of the Hazard Classification testing is included to demonstrate consistency with previous Hazard Classification tests performed on cartridges used in the Gulf War.
The Hazard Classification Tests performed on the XM919 included the Stack Test which evaluates propagation of detonation and the External Fire Stack Test which evaluates the explosive and fragmentation nature of the cartridge resulting from setting fire to boxes of cartridges. In addition, the M919 was tested against hard armor targets and against wood and masonry to determine the extent and nature of Du aerosols created.
The results of the M919 tests are as follows:
Report Number 25
Kinetic Energy Penetrator Long Term Strategy Study (Abridged), Final Report. Picatinny Arsenal, NJ: US Army Production Base Modernization Activity, July 24, 1990.
This report addressed battlefield DU exposures relative to peacetime occupational limits. Civilian battlefield exposures are not thought to be significant. "All combat-related internal and external radiation risks were in the range of 10-7 to 10-5. The most significant external radiation exposure occurs during the loading and unloading of ammunition lockers, with a lifetime increased cancer risk to the extremities as high as 3 x 10-4 resulting from a worst case, 20-year exposure. Even minimal safety precautions would reduce this risk to levels well below those tolerated in most occupational environments."
The report also addressed the following theoretical exposures;
The report also addressed the need for further evaluation of battlefield conditions. "Exposures to military personnel may be greater that those allowed in peacetime, and could be locally significant on the battlefield. Cleanup of penetrators and fragments, as well as impact site decontamination may be required." "Public relations efforts are indicated, and may not be effective due to the publics perception of radioactivity." The Overview also indicated that further studies were needed on DU combat impacts for post-combat briefings and actions.
Report Number 26
Jette, S.J., J. Mishima, and D.E. Haddock. Aerosolization of M829A1 and XM900E1 Rounds Fired Against Hard Targets, PNL-7452. Richland, WA: Battelle Pacific Northwest Laboratory, August 1990.
The purpose of this study was to characterize particulate levels after hard impact with both complete and partial penetration of the armor. Tests were performed with both the M829A1 and XM900E1 rounds, as well as two non-DU rounds (the M865 and DM13). The purpose of the non-DU round firings was to evaluate DU resuspension during hard impact tests. The sample results were questioned when the percent aerosolized was initially estimated to be only 0.2% to 0.5% for the M829A1 and 0.02% to 0.04% for the XM900E1. These values were approximately two orders of magnitude below expected values. A value of 70% has frequently been cited in the popular press based on one of the initial studies performed by Battelle for the XM774. This study stated that it was highly unlikely that more than 10% was aerosolized upon impact. In keeping with other studies indicating that a high percentage of the respirable dust from hard-impact testing was soluble in the lungs, this studys evaluation of the respirable dust fraction indicated that 57 to 76% was class "Y" material and 24 to 43% was class "D" material. (Class "D" materials have dissolution half-times less that 10 days; class "W" materials have dissolution half-times of 10 to 100 days; and class "Y" materials have dissolution half-times greater than 100 days.) The resuspension tests indicated that most of the resuspended dust was non-respirablewhich is consistent with the theory that most of the respirable dust was removed by the filtering system in the enclosure.
Report Number 27
Munson, L.H., J. Mishima, M.A. Parkhurst, and M.H. Smith. Radiological Hazards Following a Tank Hit with Large - Caliber DU Munitions, Draft Letter Report. Richland, WA: Battelle Pacific Northwest Laboratory, October 9, 1990.
At the beginning of the Gulf War crisis, Battelles Pacific Northwest Laboratory was tasked to predict potential radiation hazards to personnel entering a site where a tank has been hit by DU. Their prediction was based on a DU penetrator for a 105-mm, APFSDS-T kinetic energy round striking an armored vehicle and penetrating one side of the vehicle. No live fire testing was performed under this tasking. Their estimates were based on previous tests and their "best educated estimates" of exposures for the following scenario: The vehicle contains no DU munitions or DU armor. The event occurs in a desert-like climate, which exhibits high daytime temperatures and low nighttime temperatures and large fluctuations in relative humidity between inland to coastal areas and from day to night. There are winds associated with the changes in surface temperature. Personnel are in the immediate area for inspections and observation within days after the event. Clean up and recovery activities occur within a few weeks to a few months.
The report stated that the "impact of a DU penetrator with an armored vehicle would be expected to result in aerosolization of 12% to 37% of the penetrator, smearing of DU metal around and through the penetration, and scattering of metal fragments both inside and outside the vehicle. The aerosolized DU would most likely be oxidized uranium and form particulate material which, depending upon its size, could deposit around the immediate area and preferentially downwind. The material smeared around and through the vehicle penetration would be both DU metal and DU oxide."
The report indicated that exposures to casual passers-by and cleanup personnel would be very low. "Occupational dose limits for external exposure are 5000 mrem/year to the whole body, 50,000 mrem/year to the skin, and 75,000 mrem/year to the hands and feet (extremities). Since the most likely organ to be exposed during contact with penetrator fragments is the skin, it would require over 800 hours of direct contact to bare skin to reach the current occupational limit for skin exposure." Because such direct and long exposure is quite unlikely, the report indicated the radiological hazard from external exposure to DU fragments was very low for causal passers-by and cleanup personnel.
The report stated that the "principal hazard from exposure to DU material is inhalation and lung deposition of particulate uranium. Alpha particle emissions to the lungs from inhaled DU constitute the main health concern from the inhalation of the mostly insoluble DU. Occupational exposure limits for the inhalation of 238U are 7 x 10-11 microcuries/ml for soluble forms of uranium and 1 x 10-10 microcuries/ml for insoluble uranium compounds. These exposure limits are based on continual intake of 238U for 13 weeks at 40 hour/week. In terms of mass the limit is an average of 0.2 mg/m3 of 238U aerosols in a 40-h work week."
The report noted that 44% to 70% of the DU material aerosolized would be equal to or less than the 3.3 micrometer Aerodynamic Equivalent Diameter (AED) which is the approximate size that would be inhaled into the deep lung. Characterization of the DU penetrators oxidized in various Hazard Classification testing indicated that 0.2% to 0.6% of the oxide was less than 10 micrometer AEDwhich is considered as respirable (inhaled into the nasal passages).
The report stated that any hazards from the presence of DU are relatively insignificant as compared to the other battlefield considerations and should not be considered during life saving and rescue activities.
During the recovery operations, the report expressed concerns that the large fragments could pose a potential hazard from external radiation and their surfaces could be a source of uranium oxide contamination as they erode. The report also expressed concern that aerosolized DU which had been deposited in and around the vehicle and on the soil in the immediate area could be resuspended by wind and during cleanup and recovery operations.
The following precautions during general clean up and recovery efforts are quoted from the report:
The report also provided general guidance on routine monitoring and decontamination procedures.
The transmittal Memorandum recommended that all openings should be sealed and only external surfaces decontaminated in the field. Decontamination of the interior should only be performed in a facility set up for that purpose. The memorandum also recommended limiting intrusion into the cleanup/recovery area during periods of high winds because of the potential for contamination resuspension.
In summary, the report concluded that there is little potential for radiological hazard to personnel entering the site following the impact of a DU penetrator with a tank or other armored vehicle. (The prediction did not assume a DU round impacting an Abrams Heavy Armored vehicle with DU armor.) The report did recommend the use of respiratory protection to minimize the inhalation hazard and decontamination of the body of any fatalities before they are released.
Report Number 28
Memorandum for SMCAR-CCH-V from SMCAR, Radiological Hazards in the Immediate Areas of a Tank Fire and/or Battle Damaged Tank Involving Depleted Uranium, Letter Report, Picatinny Arsenal, NJ, December 4, 1990.
As noted in Report #27, Battelles Pacific Northwest Laboratory was tasked to predict potential radiation hazards to personnel entering a site where a tank has been hit by DU. Their prediction was based on a DU penetrator (105mm, APFSDS-T kinetic energy round) striking an armored vehicle and penetrating one side of the vehicle. The report did not evaluate a DU munition impacting an armored vehicle containing DU armor or DU munitions. The December 8, 1990 report comments on the Battelle Letter Report (Report Number 27) and expands the prediction to address DU munitions impacting an armored vehicle containing DU munitions and/or DU armor. Although no live fire testing was performed for this report, the conclusions and recommendations were drawn from BRL Technical Report BRL-TR3068, Radiological Contamination from Impacted Abrams Heavy Armor (Report Number 22 above).
The memo attempted to expand on the guidance included in TB 9-1300-278, "Guidelines for Safe Response to Handling, Storage, and Transportation Accidents Involving Army Tank Munitions Which Contain Depleted Uranium, which was the guideline for responding to peacetime accidents. The memo cited the following points:
The report also addressed potential problems caused by the sand in Gulf Region and the implication for the Armys standard radiation detection equipment. The report concluded that FIDLERS (field instrument for the detection of low energy radiation) would be more appropriate because of their larger probe areas. The report also provided supplemental procedures to TB 9-1300-278 by reiterating the radiation survey precautions cited in the Battelle Letter Report (Report #27).
Report Number 29
Mishima, J., D.E. Hadlock, and M.A. Parkhurst. Radiological Assessment of the 105-MM, APFSDS-T, XM900E1 Cartridge by Analogy to Previous Test Results, PNL-7764. Richland, WA: Battelle Pacific Northwest Laboratory, July 1991.
Due to administrative restrictions at the test ranges, this study was conducted by analogy to similar test rounds. The conclusions are that "neither propagation of initiation nor mass explosion have occurred with similar large-caliber ammunition, and it is extremely unlikely that either would occur with the M900/PA117" metal shipping container. In a stack fire, the likely extremes with the M900 cartridge are that either all projectiles would be ejected from the fire and show no evidence of oxidation or that all would remain in the fire and totally oxidize. The reality is that some would be ejected from the fire and some would be oxidized. The study cited similar tests for the M735 cartridge, which had maximum fragmentation distances up to 100 feet for the penetrator and 375 feet for the fragments.
Report Number 30
Parkhurst, M.A. Radiological Assessment of M1 and M60A3 Tanks uploaded with M900 Cartridges. PNL-7767. Richland, WA: Battelle Pacific Northwest National Laboratory, July 1991.
The purpose of the study was to assess the dose rate to which M1 and M60A3 crews would be exposed with the deployment of the 105mm M900 cartridge. The tests were conducted using worst case stowage configurations and placement of the bustle compartment near the driver. All cartridge locations were filled with M900 cartridges, rather than the mix of armor-piercing (M900) and high explosive (HE) cartridges. This is not a likely stowage situation. The dose to a crewmembers was calculated to approximate the actual radiation fields with HE stowed appropriately and taking the place of the excess DU cartridges. The results of the study are quoted as follows:
Report Number 31
Life Cycle Environmental Assessment for the Cartridge, 105MM: APFSDS-T, XM900E1. Picatinny Arsenal, NJ: US Army Armament Research, Development and Engineering Center, Close Combat Armament Center, August 21, 1991.
This Environmental Assessment was developed to address environmental concerns when the service round for the M68 cannon on the M60A3 and M1 tanks (the M833 APFSDS-T) was replaced by the new XM900E1 APFSDS-T round, which has significantly greater armor-piercing capabilities. The Assessment included previous studies of the radiological hazards, etc. conducted on the XM900E1. The Assessments conclusion was that only the testing modes for armor penetration and accuracy and final disposal of the penetrators presented any significant potential for environmental impact; the report outlined mitigating measures to reduce the impact of testing. From a health and safety standpoint, the XM900E1 presents no greater risk than the existing M833. The XM900E1 program is not expected to have a significant environmental impact on air quality, water quality, ecology (flora and fauna), or health and safety to personnel associated with normal maintenance and life cycle operations.
Report Number 32
Life Cycle Environmental Assessment for the Cartridge, 120MM: APFSDS-T, XM829A2. Picatinny Arsenal, NJ: US Army Production Base Modernization Activity, February 2, 1994.
This is an environmental assessment (EA) of the third generation M829 round (M829A2). It builds on the EA for the previous M829 and M829A1 rounds (see Report Number 18) and concludes with a "Finding of No Significant Impact." This assessment excludes combat uses and fires or other severe and unlikely accidents and the testing modes for armor penetration and accuracy. The EA recognized that the resuspension of DU, environmental transport, and various health and safety issues as areas of concern requiring further evaluation. Consequently, the Army Environmental Policy Institute has been tasked to evaluate the risks associated with depleted uranium left on the battlefields during Desert Storm. In addition, studies on the health effects of DU fragments in soldiers have been funded. The Army is also developing special DU training courses for personnel engaged in fielding, firing, and retrieval operations.
Report Number 33
Parkhurst, M.A. and R.I. Scherpelz. Dosimetry of Large Caliber Cartridges: Updated Dose Rate Calculations, PNL-8983. Richland, WA: Battelle Pacific Northwest Laboratory, June 1994.
This report provides revised exposure levels for all of the previous radiological assessments performed by Pacific Northwest Laboratory (PNL) that used the lithium fluoride thermoluminescent dosimeter (TLD). PNL developed a new, more accurate algorithm for interpreting the response of the TLD used in the radiological assessment of various DU cartridges. As a result, PNL re-evaluated the previously reported exposure values for the following cartridges:
The report also provides a comparison of the original versus recalculated values. "In all cases, the recalculated dose rates were significantly lower than the originally reported dose rates. Studies of dose rates in the tanks showed that crews in tanks loaded with DU rounds would pose no danger of exceeding administrative badging limits of 250 mrem/year and it was also unlikely that the more restrictive population limits of 100 mrem/year would be exceeded by personnel in the tanks." In other words, radiation exposure levels associated with uploaded DU munitions in the applicable tanks are within acceptable criteria, even for the general population.
All of the previously reported radiological assessment reports need to be corrected to reflect the results of the recalculations.
Report Number 34
Parkhurst, M.A., G.W.R. Endres, and L.H. Munson. Evaluation of Depleted Uranium Contamination in Gun Tubes, PNL-10352. Richland, WA: Battelle Pacific Northwest Laboratory, January 1995.
Routine radiation monitoring identified radiological contamination in gun tubes that fire developmental and production DU rounds. This report addresses the issues of how much DU is present in tubes that have fired DU, how this relates to unrestricted release standards, how cleaning techniques reduce the DU levels, and how the levels relate to personnel radiation protection.
Testing revealed that numerous tubes had detectable levels of DU in the gun barrels and some were above the unrestricted release limits, but none were high enough to pose a health risk. Firing non-DU training rounds is also effective in reducing the contamination in the tubes, but the practice is not recommended. The removable contamination makes up only a small percentage of the DU contamination that is generated in the firing process. The fixed contamination that is left behind after normal barrel field cleaning procedures was found in a number of instances to be above uncontrolled release limits. Presently, unless more satisfactorily decontaminated by other cleaning means, those barrels would have to be processed as radioactive waste at the time of turn in by the field of the barrel for disposal. Further studies were required to fully assess the problem. Induced flareback was also achieved during firing to determine if tank personnel were exposed in the turret, but no problems were identified for crew personnel.
Report Number 35
Parkhurst, M.A., J.R. Johnson, J. Mishima, and J.L. Pierce. Evaluation of DU Aerosol Data: Its Adequacy for Inhalation Modeling, PNL-10903. Richland, WA: Battelle Pacific Northwest Laboratory, December 1995.
As the name of the report implies, the purpose of this study was to evaluate the existing research data on the characteristics of DU aerosols generated under various conditions. The report is an excellent summary of the studies conducted to date, including many summarized in this report. Project summaries were included for over 20 studies conducted by Battelle Pacific Northwest Laboratory and over 20 additional studies conducted by other researchers. The evaluation focused on chemical composition, particle size, and solubility in lung fluid.
Although several areas such as resuspension and particle size distribution were cited as needing further research, the overall quality of the data was deemed as being adequate to make conservative estimates of dispersion and health effects. The report is an excellent summary of the studies conducted to date.
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