The Navy said at least 300 bits of junk and ordnance-related material have been pulled out of or near Ordy Pond, a 10,000-year-old sinkhole and possible pre-contact fishpond on the former Barbers Point Naval Air Station that has come under scrutiny by Hawaiians, historians and state officials.

Controlled detonations will be used Monday on site to destroy some of the items, including MK-24 aircraft flares used to mark submarine locations; 1-pound "spotting" charges in 100-pound practice bombs; and a spotting charge in an MK-106 practice bomb, the Navy said.

"This action is being taken to protect the public," Aaron Poentis, Navy Region Hawaii’s environmental director, said in a release Friday. "At no time will the public nor will any of the cultural and archaeological resources on the project site be at risk."

A series of detonations may be heard at adjacent Kalaeloa Raceway Park or by beachgoers at White Plains Beach, the Navy said.

The Navy said the munitions to be destroyed contain small amounts of explosives, in some cases used to mark where a practice bomb landed.

The nearly $1 million Ordy Pond cleanup is part of the Navy’s ongoing efforts to transfer land — in this case to the state — after the 1999 closure of Barbers Point, according to Naval Facilities Engineering Command Hawaii.

The 1.2-acre brackish-water pond has been caught up in controversy and questions surrounding the neighboring raceway park, whether heavy equipment should have been used around a sensitive pond environment in the area of known Hawaiian cultural sites, and how and why ordnance-related junk came to be deposited in "Ordnance Pond" in the first place.

According to a 2007 Navy study, Ordy Pond reportedly was used for the disposal of ordnance-related scrap from the late 1960s to the late 1970s.

But no detailed information about the types of ordnance disposed of was available, according to the Navy report. The study also said that during site surveys, the Navy found and removed flares and small arms ammunition, but no explosive ordnance was discovered.

Ongoing dives to look for "munitions and explosives of concern" were temporarily halted to conduct the detonations Monday.

During an ordnance survey in 1994, "they found a couple of unusual items they didn’t expect to find," said Denise Emsley, a Naval Facilities Engineering Command Hawaii spokeswoman. "They found some flares, some flare dispenser cartridges, an inert bomb fin assembly. So bits and pieces of things that shouldn’t have been there."

Emsley added that Ordy Pond was never used as a training area, "and the fact that this stuff was found (means) it was probably left there or dumped there incorrectly."

"That’s why we’re being really careful," she said.

Thick mangroves that were choking the pond were removed using excavators, loaders and backhoes to get at the ground to check for munitions, Emsley said.

Additionally, a road was bulldozed around the perimeter of the site and into the brush for a detonation and munitions storage site, officials said.

Karst coral sinkholes or caves, caused by rainwater erosion, are scattered across the Ewa Plain, some containing the bones of extinct birds.

Some sinkholes in Hawaii have anchialine pools with groundwater and a subsurface connection to the sea and are one of the most threatened aquatic ecosystems in the state, according to the U.S. Fish and Wildlife Service.

Ordy Pond was deemed eligible for the National Register of Historic Places, the Navy said.

John Bond, an Ewa Beach historian, said Ordy Pond has become a "major destruction site" with all the heavy equipment work.

"This entire Ordy Pond project has all the appearances of way too much to spend with way too little documentation," Bond said. "There could be very significant impacts to the pond water, underground karst system and very possible destruction of numerous yet undocumented archaeological sites — and even iwi kupuna burials."

The work could have been done with chainsaws and machetes to better protect the pond environment, Bond said.

According to the Navy, a $915,485 contract was awarded to Cape Environmental Management Inc. for the work.

The Navy, however, said archaeological surveys were done at Barbers Point in 1991, 1997 and 2001 by independent contractors.

Emsley said heavy equipment was used because "mangroves are not easy to get out." A Navy archaeologist has been on site and the work was coordinated with the state Historic Preservation Division, she said.

The contractor began finding ordnance-related items on Jan. 7, and as of Jan. 24 the list included the fins from a Snake Eye bomb; several MK-25 marine markers; a few MK-24 aircraft flares; two 100-pound sand-filled practice bombs; and some empty MK-104 impulse cartridges, the Navy said.

Dives were being conducted with metal detectors in the pond, which is 18 to 19 feet at its deepest point.

Both Bond and Michael Lee, a cultural descendant of Native Hawaiians buried in the area, question why an archaeological inventory survey was not conducted for the Ordy Pond site.

"How can you say you are protecting archaeological sites when you haven’t inventoried them?" Lee asked.

A May 5, 2011, letter from the state Historic Preservation Division to the Navy noted that the Ordy Pond project "area of potential effect" included 18 archaeological features and said an archaeological inventory survey would be "appropriate."

The Navy said the project subsequently was revised to "avoid all archaeological resources," so the survey was not done.

Bond said that "doesn’t appear to be the case at all," adding, "In fact, the entire project has been greatly expanded into the most important and culturally sensitive area on the former base."

Shad Kane, who is active in Hawaiian issues in the area and is part of the nearby Kalaeloa Heritage Park, was consulted on the project, the Navy said.

Kane said in an email to Hawaiian civic club members that he "identified all the cultural sites that are within the APE (area of potential effects) and there are only two, which we flagged with tape."

Most of the area had been previously disturbed by the Navy, Kane said.

"There is no wide-scale destruction of Ordy Pond or cultural sites," he said. Kane added that the Ordy Pond property would be conveyed to the state Hawaii Community Development Authority when cleared and "come under the kuleana and care of the Kalaeloa Heritage and Legacy Foundation," for which he is listed by the state as a director.

The foundation describes the Kalaeloa Heritage Park site as "a relatively undisturbed, 77-acre parcel with over 177 recorded cultural sites."

Asked how Ordy Pond would come under the care of his foundation, Kane said in an email that the Star-Advertiser would have to check with the "current landowner," the Navy.

The Navy said it was aware only that the land would be turned over to the state.

An "upright stone" of the type used by ancient Hawaiians was found on the site during vegetation grubbing and was "recently moved into its upright position by a bulldozer," the Navy said.

Lee said dust kicked up from the adjacent raceway park likely has contributed to the degradation of the pond.

George Grace III, the raceway’s operator, said during a news conference that no runoff from his business was entering Ordy Pond.

While Bond and Lee question the impacts of the Navy operation on the Ordy Pond environment, the Navy’s Emsley said the mangrove removal is expected to improve the pond.

"They are hoping once the work is done, the pond will clear out and the birds will be able to come back into it," she said.