One of the most complicated wildfire cleanup missions in recent memory is now underway on the Hawaiian island of Maui, where fleets of workers and equipment are being shipped to the island while officials plot how to carefully but quickly remove hundreds of thousands of tons of toxic debris.

Federal authorities are working with wary locals to negotiate significant logistical hurdles not found in the aftermath of blazes on the mainland United States, and they are attempting to navigate the delicate dynamics of disaster cleanup in a place as historically and culturally important as the ruined town of Lahaina.

Maui’s island geography presents the most obvious challenge, because everything that happens in the middle of the Pacific Ocean is more complex and costly. But even beyond that, it is no normal cleanup. The horrific, historic toll from last month’s wildfire — which now stands at 97 people dead and at least 23 missing — has left many residents fearing there are still human remains among the ash.

Lahaina, the former capital of the Kingdom of Hawaii, is also a sacred place for Native Hawaiians, which means the wreckage of the town is not simply waste to be hauled away en masse. The rubble contains all that’s left of irreplaceable cultural artifacts, such as ceremonial stones and burial sites. That has meant the project is not just rehabilitation, but an effort at preservation.

The cleanup process, which involves coordination among a thicket of local, state and federal agencies, will cost hundreds of millions of dollars and could take over a year to complete, as officials ship hazardous detritus to the continental United States and search for local landfills equipped to accept the remaining debris.

“If you were on the mainland at another site, you’d be able to run through there with a bulldozer” and be ready to rebuild in just a few months, said Kaanapu Kalama-Jacobsen, a firefighter for the Federal Fire Department of Hawaii who is serving as a cultural adviser to the Maui cleanup. “But here, it’s a whole different animal because of the cultural significance of Lahaina.”

In the aftermath of a disaster, the cleanup phase is a crucial and often-overlooked step along the path to recovery. This part begins after the flames are extinguished, the emergency ends and the national spotlight has moved on.

In Lahaina, homes that housed generations of families were reduced to concrete slabs and cinders. Cars caught in the scramble to flee still sit twisted and burned along the streets in pools of melted metal. Thousands of displaced residents are waiting until these fragments are cleared before they can begin rebuilding.

“Nothing can happen until the debris is cleaned up,” said Sean Smith, who served as California’s debris removal coordinator during the state’s worst-ever fire seasons. “You can’t start rebuilding until then. You’re not going to build a brand new house next to a lot full of toxic debris.”

Monday marks an important milestone, as the county begins to reopen the tightly controlled burn area to residents whose lots have been deemed safe to enter, allowing more people who evacuated weeks ago to visit what remains of their homes. Many will be seeing the area for the first time.

Teams from the U.S. Environmental Protection Agency have been working to rid properties of dangerous or potentially poisonous items such as propane tanks, fertilizers and ammunition — the first phase of the cleanup. As of late last week, nearly half of the parcels had cleared Phase 1, according to an EPA tracker. Phase 2 begins later and will involve the removal of larger debris, such as the remnants of house foundations and charred trees.

“We have not in our history had such a fire occur on a Pacific island,” said EPA Incident Commander Steve Calanog. “Getting people and things here and getting the waste off is a huge logistical challenge.”

One example occurred early in the cleanup, when EPA officials discovered that many West Maui homes were outfitted with solar-powered battery walls whose lithium-ion cells require careful disposal. With no industrial battery shredders on the island, officials would have had to ship the machines from California, which proved too costly. Instead, the EPA is using excavators to mince hundreds of power walls into small pieces safe enough to be transported off-island.

All hazardous material removed during this first phase must be loaded into containers and shipped to licensed disposal sites on the mainland, because the island does not have a facility to handle such refuse. The sites will be selected through a bid process, which has not yet taken place. This phase is expected to last at least through October. Meantime, the waste is being sorted and staged at a county-run gun range, which is temporarily operating as a makeshift storage site.

The debris that remains presents a more complicated problem. For one, there’s a lot more of it. The U.S. Army Corps of Engineers, which is leading the second phase of the cleanup, estimates that as many as 700,000 tons of ash, concrete slabs and metal scraps will need to be hauled out — about half the amount of debris removed from the World Trade Center site after 9/11.

Army Corps teams and contractors will probably truck this debris to one or more of Maui’s handful of landfills, the Corps said. Maui County has not identified which landfills will accept the debris, or said whether they have sufficient capacity, an issue that has arisen after recent California wildfires.

The Army Corps has sought to reassure Maui residents — many of whom distrust federal forces, especially those affiliated with the U.S. military — that its work will not be heavy-handed or destructive.

“The number one thing we can do right now and throughout the mission, no matter how long it takes, is be culturally sensitive,” said Lt. Col. Ryan Pevey, the Army Corps’ Honolulu district commander, whose team includes those whose family members lost homes in the fires. “We’re not going to come in there and just start scooping debris. We’re going to separate, segregate and understand what is in every single property, and do that methodically.”

The Army Corps won’t enter private property without first receiving permission from its owners, Pevey said, and they will immediately stop work if they discover human remains.

Authorities have estimated a 6- to 12-month timeline for debris removal, as they labor under the competing pressures of public expectations that it be completed quickly, but without inflicting more harm on a community that is still suffering. But they say it could stretch on longer.

“If the officials don’t plan for it, the recovery of Maui communities impacted will be much slower than we’ve seen on the mainland,” said Andrew Whelton, an engineering professor at Purdue University who has consulted with several governments, including Maui’s, following wildfires.

In addition to a prolonged cleanup effort, the island could find itself short on building materials such as wood and plastic piping, he said.

“That all has to get there by ship,” Whelton said. “So the slower it takes to get building supplies, the slower it will be for homes to get rebuilt.”

Another curveball is the possibility that a looming government shutdown could interrupt federally funded disaster response work. Hawaii’s congressional delegation has lobbied to keep money flowing to the Federal Emergency Management Agency, which is bankrolling relief efforts. Without a deal, the government is due to shut down Oct. 1.

A FEMA spokesperson said the agency has dipped into an emergency fund so that it can continue to “provide lifesaving and life-sustaining assistance in the event there is ever a lapse in appropriations.”

Calanog, of the EPA, was more direct. His team may not get paychecks if the government shuts down, but they’ll continue to work, he said, just as they did in the aftermath of the 2018 Camp Fire, when the federal government shut down for 35 days.

“I’ve been doing this 15 years, there’s been a half-dozen government shutdowns,” Calanog said. “We worked through them.”

Calanog’s team began its work in late August and brought on some two dozen cultural monitors, who accompany EPA officials as they survey properties searching for hazardous materials.

Kalama-Jacobsen, who is Native Hawaiian and has family whose houses burned, is one of those monitors. At the start of each day, he said, their group of EPA workers and Maui locals begins with a pule, or prayer, for all the spirits who are still lost in the burn zone.

Then they break into groups and begin inspecting properties. The cultural monitors scan the ruins for walls or other structures made from dry stack masonry, a storied Hawaiian stone working technique, and they look closely for stone poi pounders, which are used to crush taro root into a paste and are passed down through generations.

“It’s a long process, it’s a dangerous process,” Kalama-Jacobsen said. “It has to be done with great humility and great aloha and great understanding.”

The team is working toward moments like those that will unfold Monday, when more evacuated residents begin returning to their destroyed homes. But the emotional trips won’t be without risk.

Hawaii’s health department has said the air quality around the burn zone is mostly safe, and it has installed real-time sensors around the town. But inside the burn area, ash and dust could contain dangerous toxins such as lead, arsenic, asbestos and the chemicals known as PFAS, said Diana Felton, who works at the department of health and for years was the state toxicologist.

“Children and pregnant people should not be in this area,” she said. “That’s the biggest safety hazard in my mind.”

Others can safely enter if they are clad in the proper protective equipment and take additional precautions, Felton said. For many, it will be the first step in rebuilding their lives.

“For people going back to the impacted areas, looking through their homes, that’s so important for people’s emotional recovery, for healing, for closure,” Felton said. “It’s going to be intense.”