There’s good reason why people reentering the Lahaina burn zone are wearing protective hazmat suits: the very real dangers posed by hazardous materials layered within the mountains of debris, should things get stirred up. While air-quality monitors show safe conditions under normal circumstances, it’s the abnormal situations that require proaction: blustery winds, heavy rains or toxic ash getting airborne by people sifting through rubble.

That’s why it’s imperative for the zone to get covered as soon as possible with a sealant-like coating, in order to keep the toxic debris intact before Hawaii’s rainy season begins, usually after October. Fortunately on Monday, Maui Mayor Richard Bissen finally approved the use of Soiltac, a nontoxic, water-resistant product that forms a thin crust over debris that bonds the soil. That will help prevent the mounds of rubble from getting dislodged and spread by the elements, causing toxins and pollutants to leach into the soil and flow into shoreline waters.

The Aug. 8 Lahaina wildfire killed at least 98 people, and incinerated more than 2,200 buildings, most of them homes. In the burn zone is 400,000 to 700,000 tons of building debris and heavy metals, with ash containing microplastics and likely toxins of asbestos, arsenic and lead.

Clearly, time is of the essence to get the sealant applied.

Bissen’s approval came amid some controversy and concern over Soiltac’s safety. Despite overall agreement from scientific experts and the Environmental Protection Agency to use the sealant, misinformation and conspiracy theories spread, delaying the approval. Maui leaders must remain firm in dispelling further misinformation.

“It’s important to protect our community and our air quality and ocean waters from the harm that ash and debris can bring,” Bissen rightly said. “With EPA’s review of the product and its recommendation, along with understanding that if we do nothing we will be placing our people and environment at risk, we will proceed with the application of a soil stabilization product.”

Soiltac use will begin as soon as next week — and that’s good, given the unpredictability of weather today. Adding to the urgency: Next week, three Lahaina public schools closed since the wildfire will reopen, with nearly 3,000 students and faculty returning not too far from the burn zone.

It makes perfect sense, then, that areas of initial priority should be debris zones near those schools; near to where people whose homes didn’t burn are living; and close to the shoreline, due to the risk of potential runoff into ocean waters.

Further complicating the Soiltac timing, though, is that it can’t be applied until Lahaina evacuees have had a chance to return to, and sift through, their decimated properties. It’s a process now underway that involves the EPA, together with cultural monitors, painstakingly clearing then declaring, zone by zone, areas safe for reentry.

This is a delicate period that must be very respectful of emotions, but there is urgency to protect public health and environmental safety. There will be only this one window of time to encapsulate the toxic debris, prior to the winter season’s probable rains and higher winds.

As of Sept. 29, the EPA had cleared more than 1,000 of some 1,598 Maui parcels, and expects to finish the remaining residential sites in coming weeks. But anything that can expedite this phase, with more and wider zones being reopened quicker to returnees, must be done.

Soiltac remediation in Lahaina will take about a month to complete; it already was done last month in Kula, where a separate Aug. 8 fire destroyed 16 homes. The sealant will be sprayed only over burned structures, not entire lots, and will be removed along with the rubble. That major next phase, to be overseen by the U.S. Army Corps of Engineers, will entail debris removal for up to 12 months.

The tragedy of Lahaina is almost too much to bear, with a long recovery ahead. But today’s returns to the burn zone must be respectfully yet purposefully expedited, before the rainy season. The last thing anyone wants is for Maui’s already massive tragedy to be compounded by an environmental disaster of toxic spread and runoff that was wholly preventable.