Depleted Uranium Contamination in Hawai’i

The U.S. military has contaminated training areas in Hawai’i with depleted uranium a dangerous radioactive waste product from the enrichment of uranium for nuclear weapons and reactors.

What is Depleted Uranium (DU)?

According to the Physicians for Social Responsibility:

Natural uranium is a chemically toxic heavy metal composed of three distinct radioactive isotopes: U-238 (99.27%), U-235 (.72%) and U-234 (.01%). Because U-238 decays by emitting alpha particles and has a half-life of 4.5 billion years, uranium is modestly radioactive. Most of the radiation emitted is composed of alpha particles which are unable to penetrate most materials, including paper and skin.

Uranium is present in the air, minerals, water, and plants around us. In fact, the average human body contains 90 micrograms of uranium. Nuclear power plants use enriched uranium as fuel. Enriched uranium is created by increasing the proportion of the more radioactive isotopes.

DU is the by-product of the enrichment process, termed “depleted” uranium because it is 40% less radioactive than natural uranium. It shares uranium’s chemical toxicity as a heavy metal, which is independent of its radioactivity. It is classified in the lowest hazard class of radioactive materials. DU is not a nuclear weapon because its use does not trigger a nuclear chain reaction.

The dense and toxic metal has a radioactive half-life of 4.5 billion years years and emits alpha radiation, which is most dangerous when ingested in the body.  Depleted uranium has been widely used by the U.S. military in armor-piercing munitions because of its density and pyrophoric properties (i.e. it readily burns at high temperatures that can melt armor plating).  These munitions were heavily used in Iraq and Bosnia and have been linked to increased risk of cancers, genetic damage, neurological damage, kidney damage and immune system disorders.  Many unexplained health problems in Iraq and among veterans of the Gulf and Iraq wars suspect that DU contamination may be a cause.

Depleted Uranium is a regulated nuclear material that requires Nuclear Regulatory Commission license to possess and use.

For many years the U.S. military has denied using depleted uranium in Hawai’i.

In 2001, the American Friends Service Committee Hawai’i Area Program filed a Freedom of Information request for information about depleted uranium within the Pacific Command area of responsibility (PDF).

In 2005, plaintiffs in the Makua lawsuit received documents from the Army through discovery. These documents included a set of emails indicating that chemical weapons and depleted uranium were discovered in Schofield Training Area.  DMZ-Hawai’i / Aloha ‘Aina and other groups held a press conference to bring this information to the public.


The Army was forced to disclose information to the public about the DU contamination and have conducted studies and environmental monitoring. The Army revealed that the source of the DU was a classified nuclear weapon called the “Davy Crockett” Light Weapon M28.  The Davy Crockett was made to fire the Mk-54 warhead, which weighed about 51 lb (23 kg), with a selectable yield of 10 or 20 tons.

In the 1960s the Army trained to use the Davy Crockett at several ranges in Hawai’i by firing the 20 mm M101 spotting round containing DU.   The Army’s surveys discovered that Pohakuloa on Hawai’i island was also contaminated with DU, and possbily Makua valley as well.  The Army’s website on DU at Hawai’i installations contains a number of reports. Apparently, Hawai’i was not the only place contaminated with the Davy Crockett DU.   The DU contaminated sites include:

  • Fort Benning, GA
  • Fort Campbell, KY
  • Fort Carson, CO
  • Fort Hood, TX
  • Fort Knox, KY
  • Fort Lewis, WA
  • Fort Riley, KS
  • Schofield Barracks, HI
  • Pohakuloa Training Area, HI

Nuclear Regulatory Commission License Application

The Army had caused enough DU contamination to require that it obtain from the Nuclear Regulatory Commission (NRC) a license to ‘possess’ DU.   To review the application and other documents, visit

  • Click on “begin ADAMS search”.
  • Select “Advanced Search”
  • Enter docket number “04009083”

The Army plans to leave the DU contamination in place in Lihu’e (Schofield) and Pohakuloa with an environmental monitoring system in place.

The community demands that the Army halt all activity that could resuspend the contamination such as live fire training, fires and troop maneuvers and clean up the contamination.  Hawai’i Island County Council passed a resolution calling for a moratorium on live fire training activities at Pohakuloa, but the Army has refused to abide by the laws of the local government.

The NRC has the power to limit the Army’s activities under the license, but is not inclined to do so.   There is another type of permit that the NRC can issue for the ‘decommissioning’ of a nuclear site.   Both Schofield and Pohakuloa should be ‘decommissioned’ and restored to its natural condition.

October 13, 2009 is the deadline to request a hearing as described in the Federal Register.

Comments may be sent to:

John Hayes, US NRC,

Two White Flint North, Mall Stop T8F5

11545 Rockville Pike

Rockville, MD 20852-2738

Telephone: 301-415-5928

Fax: 301-415-5369



Health Effects:

  • Depleted and enriched uranium affect DNA in different ways (2010) Depleted uranium had a different effect on DNA than enriched uranium. It altered the number of chromosomes in the cell. These effects are due to improper migration of chromosomes when cells divide. This type of damage – called aneugenic damage – was not related to the amount of radiation the cells received and was likely caused by the metal properties of uranium.

Exposure Pathways:

  • Uranium travels nerves from nose to brain (2010) Radioactive uranium that is inhaled by soldiers on the battlefield and by workers in factories may bypass the brain’s protective barrier by following nerves from the nose directly to the brain.
  • Leaching of depleted uranium in soil as determined by column experiment (2005) Study of the leaching of DU from fragments embedded in soil and exposed to water.  “Assuming that corrosion and leaching continue as observed, the mobilisation of 238U from DU munitions will last, on an average, for thousands of years in the soils investigated, while the munitions themselves will have been corroded after a much shorter time.
  • Location, identification, and size distribution of depleted uranium grains in reservoir sediments (2006) This study looked at the level of contamination and possible transport pathways for DU particles in the sediment of a reservoir near a DU plant.  The report queried:  “What does the presence of depleted uranium particles from the bottom of a reservoir that is about 1 km from the site of National Lead tell us of how the particles arrived? In principle the particles could have been deposited from the air onto the surface of the soil close to the plant and then carried by runoff during and following rain into the reservoir, or they could have been deposited directly from the air (or swept out by rain) onto the surface of the water and then settled to the bottom. The former route appears difficult, but, alternatively, is atmospheric transport adequate to distribute dense, 3-mm particles radially to at least 1 km?”
  • Sorption and bioreduction of hexavalent uranium at a military facility by the Chesapeake Bay (2006) This article looked at the Aberdeen Proving Ground where DU weapons are tested and sought to understand why DU was not detected in the Chesapeake Bay nearby at the levels predicted by modeling.   They concluded that certain geological and biological processes and features may bind the DU and prevent its mobility.  However the report gave this caveat: “During extreme climate events such as heavy rainfall, both uranium species will be susceptible to erosion and flushing into the estuary even when tightly bound to NOM and other particulates present at the site. In addition, reoxidation of U(IV) to U(VI) potentially may lead to remobilization of the heavy metal and radionuclide.”