The Army said today that the results of a depleted uranium study at Pohakuloa Training Area on the Big Island show radiological doses “well within limits” considered safe by the U.S. Environmental Protection Agency.
The Army studied the potential health risk posed by residual DU in Pohakuloa areas where past and current weapons firing has taken place.
The report is expected to be released this afternoon, the Army said.
Depleted uranium, a weekly radioactive heavy metal, was used in aiming rounds for the Davy Crockett, a 1960s nuclear device intended as a last-ditch weapon against masses of Soviet soldiers in the event of war.
Jim Albertini with the Malu Aina Center for Nonviolent Education & Action said today that the Army is “stonewalling community involvement in seeking the truth about DU radiation contamination at Pohakuloa.”
Albertini said the Army has made unreliable safety claims based on questionable assumptions, scientific methodology, and no peer reviewed studies.
“The bottom line is this,” Albertini said. “The Army does not want to risk having to shut down Pohakuloa if it is determined that the presence of DU and other military toxins pose a threat to the health and safety of the troops who train there and residents and visitors of Hawaii Island.”
The Pohakuloa study is the second determination by the Army that DU poses no health threat.
The Army in 2005 discovered DU spotting rounds at a Schofield Barracks firing range. Even though the Army in 2008 said there was no danger, officials said today the DU at Schofield is being removed because Stryker armored vehicles and soldiers will be training at the Schofield site.
The DU at Pohakuloa will remain in place at the impact site “because there’s nobody out there. It’s no-man’s land,” said Army spokesman Dennis Drake.
A shipping list showed that at least 714 of the spotting rounds, containing about 298 pounds of depleted uranium, were sent to Hawai’i between 1962 and 1968, the Army previously said.
The approximately 7-inch aiming rounds were launched by a gas piston. The device was attached to a recoilless rifle that could fire a 76-pound nuclear warhead. Only dummy warheads were used in training in Hawaii.
The weapon could be fired up to three miles but likely would have irradiated the soldiers using it. Then-Attorney General Robert F. Kennedy witnessed a test fire and detonation of a Davy Crockett — at the time a classified weapon system — in Nevada in 1962.
Depleted uranium was used in spotting rounds because of its weight. The projectile, which gave off smoke on impact, was used in training to simulate the trajectory of the weapon’s nuclear warhead.
The spotting rounds are believed to have been fired mainly at Schofield and Pohakuloa, but the Army said they also may have been used at Makua Military Reservation.
DU was found within the boundary of the Pohakuloa impact area in October of 2006.
Albertini is concerned that DU particles can be ingested from the soil or inhaled as airborne dust and cause adverse health effects.
According to the World Health Organization, "very large amounts of dust" would have to be inhaled for there to be an additional risk of lung cancer.
Uranium is used primarily as fuel material in nuclear power plants. Most reactors require enriched uranium, which is extracted from naturally occurring uranium. The uranium remaining after removal of the enriched fraction is called depleted uranium, or DU, which has about 60 percent of the radioactivity of natural uranium.
DU is favored for armor-penetrating ordnance because of its high density, which is approximately twice that of lead.
Russell Takata, program manager for the state Health Department’s Noise, Radiation and Indoor Air Quality Branch, previously downplayed the possible risks of DU at the Big Island military training range.
"This is not something that’s an imminent danger," he said.
The Army said it looked at “exposure scenarios” for range maintenance workers, future construction/clean-up workers and subsistence farmers living at the site boundary, among others.
The study considered incidental swallowing of soil containing DU, dust inhalation, skin contact with DU, and direct exposure to gamma radiation.
Although access to the Pohakuloa impact area is controlled and restricted to certain personnel, the Army said it is taking additional steps to ensure the health and safety of workers and that the local community is protected.
The Army said it submitted a license application, which the U.S. Nuclear Regulatory Commission is processing, to possess the residual DU in the impact area.
Additionally, the Army said it requires that those allowed access to the impact area are qualified and trained to identify DU and to follow safety precautions while on site.
The health study will be available today at the website www.garrison.hawaii.army.mil/du, the Army said.