More Munitions Found At Hawaii's Ordnance Reef, ENS, 03/29/07
Source: Environment News Service
HONOLULU, HAWAII - Preliminary data from a study of military munitions dumped in the sea off the west coast of Oahu 60 years ago show they pose no immediate danger to the public or the environment. Nine clusters of munitions not previously identified were found near shore in addition to about 2,000 munitions found in the area by U.S. Army divers in 2002.
Requested and funded by the Department of Defense, DoD, the study was conducted in response to the concerns of local communities. Scientists from the National Oceanic and Atmospheric Administration, NOAA, the University of Hawaii, and the Hawaii Department of Land and Natural Resources participated.
The University of Hawaii research vessel Klaus Wyrtke heads out to the study area. (Photo courtesy NOAA)
For two weeks in June 2006, scientists combed an area of five square nautical miles off Pokai Bay, just offshore of the town of Waianae, known locally as Ordnance Reef. This reef lies in water approximately 10 to 70 meters (40 to 225 feet) deep.
The survey team deployed a remotely operated vehicle and trained scuba divers to collect water, fish and sediment samples for analysis by scientists at the University of Hawaii and two independent laboratories. They used seafloor mapping and imaging equipment to determine the boundary of the munitions area and the presence of explosives and metals.
Ninety-six sediment samples and 49 fish were collected and all were analyzed for metals. All of the fish and a portion of the sediment samples were also analyzed for explosives. Water samples were collected and processed for salinity, dissolved oxygen, pH and temperature.
The survey verified the presence of munitions ranging from small arms projectiles to large-caliber artillery projectiles and naval gun ammunition. About 100 previously undiscovered munitions were found in nine clusters near shore.
No explosives or related compounds were detected in the fish samples taken during the survey. With the exception of copper, metal levels in sediment samples from the study area were low overall.
Naval ammunition found on Ordnance Reef (Photo courtesy NOAA)
Most munitions were covered with coral growth and provided some of the only refuge for fish on the otherwise uncolonized hard bottom, said Ordnance Reef survey chief scientist Michael Overfield, a marine archaeologist with NOAA's National Marine Sanctuary Program.
"We weren't able to establish a total count because of the condition of the munitions," Overfield said in a media briefing by teleconference. "They are covered in coral and blended into the environment out there, which is teeming with sea life," he said. "We didn't want to disrupt the corals to see how many munitions were underneath."
The munitions were found in depths ranging from 24 feet to the maximum depth of the study area, 300 feet. Scientists did not detect the presence of the explosives cyclonite, RDX, trinitrotoluene, TNT, or tetryl during the sampling effort. A related munitions compound, dinitrotoluene, DNT, was detected in four sediment samples - three near munitions and one that is not associated with munitions.
Munitions found on Ordnance Reef (Photo courtesy NOAA)
J.C. King, assistant for munitions and chemical matters with the U.S. Army, said the military will "work closely" with federal agencies, Hawaii state agencies and local communities to determine what to do next, but that no immediate cleanup is planned.
"The final report is now being analyzed by government and military agencies," said King. "Once their analyses are complete we will understand better what the data means and what response might be required. We have asked for their assessments to be provided by the end of next month. We will finish our process by late summer."
The Army Center for Health Promotion and Preventive Medicine, the Navy Environmental Health Command, and the Defense Department's Ordnance Security and Safety Agency are among the military divisions reviewing the report.
The federal Agency for Toxic Substances will be working with the military on assessing potential risks and validating the military assessment, said King.
Overfield and King both said it is safe to fish, to swim, and to dive on Ordnance Reef. "These munitions have been there for more than 60 years," said King, who is a diver.
King said the Defense Department is required by Congress to do an inventory of munitions dump sites in U.S. waters 200 miles off the coasts of the USA and territories by 2009. Military analysts are now assessing the precise locations but King said two will be in the Hawaiian islands, two will be in Alaska, one in the Atlantic, and one in the Pacific.
Naval Station Pearl Harbor on the Hawaiian island of Oahu (Photo courtesy U.S. Navy)
He said one of the Hawaiian locations is probably going to be just south of Pearl Harbor. This summer, based on funds obtained by Senator Daniel Inouye, a Hawaii Democrat, King said University of Hawaii scientists are looking at a site south of Pearl Harbor yet to be defined, where chemical munitions were disposed.
Chemical munitions were dumped off Pearl Harbor in several places, King said - one 10 miles out, one five to six miles out, and one just two miles out in water 1,500 feet deep. "Mustard agent was found in 1999 just south of Pearl Harbor in very deep water," King said.
"The Waianae work gives us a basis of understanding," he said. "Whether the Waianae survey will be used is yet to be decided."
At the time the munitions were dumped at Ordnance Reef and elsewhere, it was common practice and was not illegal. From the early 1700s, it was acceptable to use the ocean to dispose of munitions, King explained. In 1971, Congress passed a law against munitions disposal at sea.
The Defense Department has its own Three Rs that the members of the public should know when encountering munitions underwater or anywhere else, said King. They are - Recognize, Retreat, and Report to 911 so that specially trained military personnel can respond to the situation.