Members of the NOAA "Ordnance Reef" survey team retrieved a sidescan sonar seafloor imaging device during the June 2006 survey. DAVID HALL | NOAA

"There is no immediate threat to the public or the environment," said J.C. King, assistant for munitions and chemical matters for the Army.

"A couple thousand" individual munitions were detected in the two-week survey, with munitions ranging from .30-caliber rounds to large-caliber artillery projectiles and naval gun ammunition, said Michael Overfield, marine archaeologist and Ordnance Reef survey chief scientist for NOAA.

The survey was conducted by NOAA, with assistance from the University of Hawai'i and the Hawaii Department of Land and Natural Resources.

No explosives or related compounds were detected in 49 fish samples taken during the survey. With the exception of copper, metal levels in sediment samples from the study area were low overall.

As a result of the survey, no cleanup of the area is planned.

The munitions were found in depths ranging from 24 feet to 300 feet — the maximum depth of the study area.

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.

Scientists studied the 5-square-nautical-mile area off Pokai Bay known as "Ordnance Reef" with seafloor mapping and imaging equipment to determine the boundary of the munitions area and the presence of munitions constituents, such as explosives and metals.

The survey team deployed a remotely operated vehicle and scuba divers to collect water, fish and sediment samples for analysis by the university and two independent laboratories.