With news of possible further mining of the sand dunes of Central Maui, the Office of Hawaiian Affairs Board of Trustees has formally called for a halt to the practice.

Saying they have a responsibility to protect the bones of Native Hawaiians buried in the dunes, the trustees voted Thursday to urge Maui County officials to determine if sand extraction violates the Maui zoning code and whether they can revoke or suspend the grading permit issued to developer Maui Lani Partners.

The trustees also urged the State Historic Preservation Division and the Maui Lanai Islands Burial Council to investigate the discovery of burials in the dunes there and whether historic preservation laws and conditions are being complied with and enforced.

“The community wants immediate action to preserve the sand dunes,” OHA CEO Kamana‘opono Crabbe said.

Developer Maui Lani Partners and contractor HC&D agreed to stop moving sand from Central Maui at the beginning of May after the county informed them that the operation may require a special or conditional use permit.

But activists say they discovered active sand operations last week at the company’s sand mining area near Maui Lani Parkway and west of the Dunes at Maui Lani Golf Course.

Maui Lani Partners couldn’t be reached for comment Friday.

Maui County spokesman Rod Antone said the county Planning Department and Department of Public Works are still reviewing the work performed last week to check compliance with the grading permit and county zoning laws on resource extraction.

Maui’s sand dunes were built up over thousands of years with small wind-blown grains that are spread out across the vast Central Maui isthmus from coast to coast.

Jocelyn Doane, OHA public policy manager, said the dunes have “immense cultural value and (are) well known for having iwi (bones) from battles and from other burials.”

Sand has been mined on Maui since before World War II, but the activity increased in the 1970s as Maui’s inland dunes became the source of sand for concrete used to fuel a construction boom.

By 1985, Maui sand started being barged to Honolulu, and over a couple of decades 5.5 million tons were shipped to Oahu for use in construction, according to a 2006 report compiled for the county Department of Public Works and Environmental Management. The report had estimated the sand could be depleted in less than 10 years.

According to Doane, the Maui Lanai Islands Burial Council in 2009 asked for an accounting of burials affected by the sand mining, but nothing came of it.

The mining continued and reportedly has been a source of sand for the concrete used to build the pillars and guideways of the Honolulu rail project now under construction.

After community members brought the resource depletion and archaeological concerns to light a few months ago, Maui Mayor Alan Arakawa called for a sand export moratorium, and the Maui County Council began looking at solutions to the problem.

The county Planning Department in late April issued a formal notice of warning requiring the mining and transporting to stop while a review of the applicable laws takes place, although the warning doesn’t apply to all sand-moving activity, including cleanup, erosion control and safety measures on the property.

“This is the time to come forward,” Maui activist Clare Apana told the OHA trustees Thursday. “The sand of our kupuna (ancestors) is in those rail columns.”

In an emotional plea for help, Apana said the bones of Native Hawaiians are being “sand mined and sold as a commodity and put into concrete to build a rail that half the city does not want. I think they deserve better, and we can do better.”

Native Hawaiian burials are commonly found in sand dunes, and OHA’s 2015 iwi kupuna (ancestral bones) policy describes the human remains as “the most cherished possession within our lahui (nation).” The policy calls for the care, management and protection of iwi kupuna.

Several trustees last week suggested that OHA go to court over the issue.

“They’re just digging away all this sand with iwi in it. It’s sad,” trustee Lei Ahu Isa said.

“We have to do something now. We can’t wait any longer,” Maui trustee Carmen Hulu Lindsey added.