The material is not considered hazardous or toxic by regulation and does not pose a direct risk to human health. Human health risk is evaluated by:

• Considering the toxicity of a substance,
• A person’s likelihood to have contact with it,
• How much a person may come into contact with,
• How it gets into the body, and
• How long a person might be in contact with the substance.

Ash and debris from fire-affected properties were removed and taken to the TDS site because it contained metals (such as antimony, arsenic, lead, cobalt, and copper), which occur naturally as well as in man-made materials. Some substances are healthy in certain quantities but unhealthy at high quantities.The levels of contaminants originally detected may have posed potential health risks with prolonged, direct exposure. For this reason, it was removed as quickly as possible from impacted parcels in Lahaina.  

During removal from the TDS site, transport, and placement at the PDS, these substances no longer pose a public health risk because they are mixed with underlying soils, wetted down, wrapped, and covered, thus greatly reducing the likelihood, amount, and duration anyone may come into contact with it. The debris is suitable to be disposed of at the PDS, which was built to meet or exceed current solid waste landfill standards as defined in Subtitle D of the Resource Conservation and Recovery Act. Other fire debris materials which may have posed a potential health risk were not transported to the TDS:

• Household hazardous material and bulk asbestos material was separated from other debris and shipped off island for disposal.
• Debris from commercial lots that initially exceeded hazardous screening levels were rendered non-hazardous before transport to the TDS site.
• Batteries from electric vehicles and power boards were shipped off island.

Environmental monitoring in the community and adjacent to the cleanup, including thousands of air samples, confirmed that no substances from the fire debris were released to the surrounding areas at levels of concern. No asbestos was detected in air monitoring, and heavy metals were either non-detect or at levels below human health concern consistent with background levels. Similarly, sampling and analysis of groundwater and leachate at the TDS site, coastal waters, coastal sediment, and beaches also did not identify any chemicals at levels of public health concern. All data collected, along with explanations of why, how, and where samples were collected, can be found at the DOH Maui Environmental Data Portal. For more information about how DOH assesses environmental hazards and develops environmental action levels, see DOH EHE and EAL guidance.

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DOH collected samples for laboratory analysis of the ash from parcels in Kula, Olinda and Lahaina. DOH’s ash characterization testing screened for heavy metals, polyaromatic hydrocarbons (PAHs), residual range organics, dioxins and furans, per- and polyfluorinated substances, flame retardants such as polybrominated diphenyl esters and organophosphates esters, asbestos, and organochlorine pesticides.

These results found elevated levels of arsenic, lead, antimony, copper and cobalt at levels determined by health agencies to be potentially harmful to humans in direct contact with it, which is why it needed to be collected and removed from the ground as soon as possible to reduce the risk of rainwater run-off or wind erosion.

DOH only conducted testing ash atop the rest of the debris (which included brick, cinder block, concrete, asphalt, steel, wood, plastic, glass, rubber, etc.). This ash was part of the overall waste removed from impacted parcels, which also included a 6-12” layer of soil from around structures. This ash was mixed with underlying soils and debris prior to removal from the parcel.

Ash and debris from commercial structures were sampled and analyzed by USACE and their contractors and sent to a laboratory to determine if the material was hazardous and therefore subject to stricter handling, management and disposal requirements. A sampling and analysis plan was utilized for ash and debris from commercial properties. The material was separated and/or stabilized prior to removal from the parcel.

• Antimony is naturally present in soils. The general population is exposed to low levels of antimony from ingestion of food and drinking water and possibly by inhalation of particulate matter containing antimony in ambient air.
• Arsenic is a heavy metal found in soils in Hawaii due to volcanic soils and its use as an herbicide in the early 1900s. It is also found in building materials made of sugar cane (Canec) and wood treated for termite control (CCA treated wood). Arsenic can also be found in food such as rice, meats, fish and seaweed and has also been found to be naturally occurring in well water around the world. Long-term, environmental exposure to arsenic can cause skin problems, heart problems and cancers of the skin, bladder and lungs.
• Cobalt is a naturally occurring element that is essential for certain functions of the body including the generation of red blood cells. People are exposed to small amounts of cobalt in food, industrial air pollution, and many cosmetics. However, when people are exposed to excessive amounts of cobalt, it can cause problems with the blood, lungs and skin. Cobalt may also cause cancer with extreme exposures.
• Copper is a chemical element and essential trace mineral that is a reddish metal which occurs naturally in rock, soil, sediment, water, and at low levels, air.  Lead is particularly toxic for young children and babies in utero as it hinders the development of the brain. Babies and children exposed to lead have trouble with learning, school performance, attention, and other neurocognitive problems.
• Lead is a heavy metal that is expected to be present in ash due its use in paint on houses built before 1978.
• Dioxins and Furans were detected in ash samples collected by DOH at levels not considered harmful to human health according to DOH guidance. Dioxins do not typically exist in materials before they are incinerated. However, when materials and waste are burned, dioxins are produced and introduced into the environment. A large part of current exposures to dioxins in the U.S. is due to releases that occurred decades ago (e.g., pollution, fires). Even if all human-generated dioxins were eliminated, low levels of naturally produced dioxins would remain. More than 90% of typical human exposure is estimated by USEPA to be through the intake of animal fats, mainly meat, dairy products, fish, and shellfish. For more information, see USEPA’s ‘Learn about Dioxin’ website.
• Bulk asbestos containing material (ACM) found on parcels was removed by USEPA during Phase 1 operations and shipped off-island. Similarly, USACE removed and shipped off island any remaining bulk ACM during Phase 2 operations. Building materials such as siding, caulk, floor tiles, and insulation which may contain small amounts of ACM were controlled by application of a gentle water spray for dust control during transport and handling at both the TDS site and PDS to eliminate any exposure.

There are not sufficient concentrations of contaminants in the material being hauled that would pose a public health concern. Response plans have been developed by USACE and their contractor to contain any oil or fuel spill, manage traffic, and clean up any debris. Controls utilized during ash & debris handling and transport, such as wetting down to control dust, wrapping in thick plastic sheeting, and tarps on trucks, prevent direct exposure to the public as well as release to the environment.

Upon the completion of the construction of a permanent debris site, transfer operations began in June 2025 and are expected to take approximately five months.

The nonhazardous debris is being transported via dump trucks from the Temporary Debris Storage site (TDS) at Olowalu to the Permanent Disposal Site (PDS) in Central Maui using the most direct routes. On the primary route, trucks will travel a 19-mile route from Olowalu to Central Maui using Honoapi‘ilani Highway (HI-30), Kūihelani Highway (HI-380), and former cane haul roads beginning from Waikō Road. Two alternate routes have also been identified for use in case of unplanned road closures.

Based on engineering analysis by the U.S. Army Corps of Engineers, impacts to traffic will be marginal, but USACE is working with their partners to mitigate them. The existing temporary traffic signal at Olowalu will be utilized to allow trucks exiting the TDS to turn left safely onto Honoapi‘ilani Highway. Drivers should plan additional time into their drive to accommodate any delays.

Debris at the TDS site will be lightly wetted for dust control. It will then be loaded into trucks and securely wrapped in thick, industrial-strength plastic sheeting. The loaded trucks will be weighed and then begin the route to the Central Maui Landfill. Approximately 50 trucks will make approximately four round trips per day during daylight hours.

Work will be done during daylight hours to prioritize the safety of workers at the TDS and PDS sites, where heavy machinery will be operated.

The cost of the transfer operations and sites are federally funded, and under the County of Maui’s agreement with FEMA, the debris transfer and subsequent restoration of the Olowalu site by USACE must be completed by the end of the year. The beginning of transport in June is contingent on the completion of the permanent site at Central Maui Landfill.

No. There were no cars stored at the TDS. Burnedvehicles had already been recycled as scrap metal following an adjudication process coordinated by the County of Maui’s Department of EnvironmentalManagement.

USACE recognizes the importance of supporting the local contracting community and the economy. USACE’s prime contractor is the Environmental Chemical Corporation (ECC). A significant portion of their subcontractors and workforce will be local hires.

The contractor has strike teams on standby to providerapid support to minimize impacts to traffic should there be a need.

The nonhazardous debris will be wrapped in thick, industrial-strength plastic sheeting and lightly wetted prior to being placed in a truck at the TDS to prevent fallout during transport. If a member of the public sees something of concern, please report the incident and license plate number of the truck to the USACE debris hotline at 877-214-9117.

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Trucks have been issued placards providing a truck number and appropriately identified with a magnetic decal.

Unfortunately, to make maximum use of optimal weather conditions in wind-prone areas, transport operations must be conducted during the morning and late afternoon hours. Any project delays could impact the project’s completion within the required timeframe to receive federal funding.