Reference Library

Soilworks products are the industry’s top standard due to our insistence on creating high performance soil stabilization and dust control products that stand up to rigorous testing – both in the lab and in the field. Our commitment to quality and performance has led to our involvement and testing in hundreds of real-world situations. The following library of reports, presentations, specifications, approvals and other similar documents provide you, our customer, the transparency and dependable assurance that is expected from Soilworks.

EPA Maui Wildfire Recovery Factsheet – FAQ About Using Soiltac Soil Stabilizer on Properties with Ash and Debris (TPD2310049)

Maui Wildfire Recovery

Frequently Asked Questions About Using Soiltac® Soil Stabilizer on Properties with Ash and Debris

October 19, 2023

Maui gives so much to the world. As guests, we are honored to give our support back.

Ash and debris on properties affected by wildfires on Maui may impact wildlife, marine life, and people’s health as they can contain harmful contaminants like asbestos, lead, and arsenic. Ash and debris can spread by wind, rain, re-entry, Phase 2 debris removal, or events where ash is disturbed.

Who made the decision to use a soil stabilizer?


Maui County—with the Hawaiʻi Department of Health (DOH), Federal Emergency Management Agency (FEMA), United States Army Corps of Engineers (USACE), and EPA—requested using soil stabilizer to control ash and dust in the areas impacted by the wildfires.


EPA successfully applied soil stabilizer in Kula on September 25, 2023, and after the Mayor approved applying Soiltac® in Lāhainā in mid-October, EPA began applying it thereafter.


What are the implications of ash and debris on human health?


Ash and debris can contain harmful contaminants like asbestos, lead, arsenic, and other hazardous substances.

  • Short-term exposure may cause lung, throat, and nasal irritation including sneezing, coughing, shortness of breath, allergic reactions, and intensified asthma It also can cause eye irritation and infections, and skin irritation.
  • Long-term exposure may increase risk of heart disease, strokes, and lung cancer and diseases that

impact breathing and cause infections.


For more information on the impacts of ash on human health, please go to: health.hawaii.gov/mauiwildfires/


What are the benefits of using a soil stabilizer?


  • Using a soil stabilizer reduces the chance of people breathing in
  • It also helps prevent ash from spreading off
  • If a soil stabilizer is not applied, the risk of ash running-off into the watershed and causing damage to the ecosystem will be greater. Specifically, ash could wash onto the reef and coastal marine


Where will the soil stabilizer be applied?


  • EPA teams will apply a soil stabilizer on ash and debris on the footprint of burned


  • Teams will be closely supervised to ensure all health and safety guidelines are followed and that

residents and workers are protected.


What is the protocol to apply Soiltac?


Before application, EPA teams and cultural monitors will closely study the building footprint and surrounding area to ensure wildlife, animal feeders, personal items, or other unintended items are not impacted by application.


Soil stabilizer will not be applied to historic or cultural areas or items previously known or flagged by cultural monitors.

  • In the event an item of cultural significance is identified by cultural monitors, crews will work around the item and it will be further investigated for next steps.
  • Examples of cultural and historic structures that will not be sprayed include:
    • burial sites,
    • walls,
    • temple bells, historic structures, such as Waiola Church, Pioneer Mill Office, and the Lahaina Store, and
    • known collections of artifacts and ancestral ashes at the Baldwin House, Wo Hing, and Shingon


What does ash and debris look like after it is treated with soil stabilizer?


  • Soiltac® dries It is non-toxic when dry, and commonly used for dust and soil control.
  • Its transparency will allow S. Army Corps of Engineers to see what is underneath during Phase 2 ash and debris removal.


Will people be able to sift through their properties after the soil stabilizer has been applied?


  • Yes, people searching properties can easily see underneath the clear coating and break through to sift ash, if desired.
  • EPA requests people wait 24-hours after application to sift through debris when it becomes fully effective. EPA will post signs at the property to indicate the time of application.


What if I disturbed the soil stabilizer? Can you come back to re-apply it?


We anticipate there will be a need for reapplication based on significant disturbances (after it has been applied), weather events, and/or solar degredation. But our first objective is to apply the soil stablizer to all ash footprints. For more information, please contact our hotline at: (808)-539-0555.


How long will the soil stabilizer be effective?


The soil stabilizer is effective for four to six months if it is not disturbed.


How long will the soil stabilizer remain on properties and when will it be removed?


Soil stabilizer is not intended to permanently control ash. After residents visit their properties, the U.S. Army Corps of Engineers will remove ash, debris, and the soil stabilizer during Phase 2.


Can residents opt out of soil stabilizer application?


Residents cannot opt out of soil stabilizer application. Soil stabilizer will be applied to all properties in Lāhainā to protect residents’ health and fragile coastal and marine ecosystems.


Can I remove Soiltac® from something I retrieve from my home?


Yes. Run it under hot water or steam it, then wipe the surface with a soft cloth. The Soiltac® will remain non- toxic, even during removal.



For more information regarding the above uses please visit: soilworks.com/reference-library


Find more information about EPA’s support of the Maui wildfires response at: epa.gov/maui-wildfires


For more info about EPA’s work, contact us at:


Email: R9Wildfiresinfo@epa.gov

Phone: (808)-539-0555

Or visit: epa.gov/maui-wildfires facebook.com/EPAregion9 twitter.com/EPAregion9 instagram.com/epagov


mauicounty.gov and mauinuistrong.info

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