Action Update: EPA Identifies the Spilled Chemical Compound in Garnett, Kansas

The U.S. Environmental Protection Agency (EPA) has identified the chemical compound spilled in Garnett, Kansas, on Dec. 31, 2025. Recent laboratory analysis corroborates EPA’s preliminary field screening results with a “high level of confidence” that the corrosive substance was sodium aluminate. 

Field tests were conducted early in the response and identified the material as a strong base with a pH level of 14. Strong bases are reactive chemicals that undergo various chemical changes when they are exposed to the elements. These characteristics made collecting a pure sample for broad-spectrum analysis difficult. Substances with a pH of greater than or equal to 12.5 are considered hazardous based on the Resource Conservation and Recovery Act’s corrosivity characteristic.

“I want to thank the people of Garnett and Anderson County for their patience and cooperation with EPA and our partners during this response,” said EPA Region 7 Administrator Jim Macy. “Applying sciences in the field and taking the time to ensure accurate results is an important part of the emergency response process that takes time to get accurate results. We want to be confident in both our field and laboratory analyses before announcing results to the public. Communities in the Heartland should know that if any substance posed an immediate threat to life or their health, EPA would notify them and take immediate action with the help of local first responders.”

The laboratory conducting the analysis was able to account for chemical byproducts and reactions in the samples of the spilled material. The identification of the material as sodium aluminate supports EPA’s initial field screening techniques and analyses conducted at the response. These analyses enable EPA’s responders to characterize substances and direct responses appropriately.

Sodium aluminate is a chemical compound that is typically used in water and wastewater treatment, paper and glass manufacturing, and as a solidification accelerant in the construction industry. EPA responded to the spilled sodium aluminate in Garnett, Kansas, to prevent potential human exposure to the material after the material was spilled along two miles of roadway and impacted over 260 vehicles by an unknown, and still unidentified, party.

Throughout the week of Jan. 4, 2026, EPA treated 266 impacted vehicles in Garnett with a vinegar-water solution followed by a traditional car wash.

EPA worked in Unified Command along with its partners the Kansas Department of Health and Environment (KDHE), the Kansas Department of Transportation (KDOT), Anderson County Emergency Management, and the City of Garnett.

EPA ended its no cost car treatment operations to prevent potential human exposure to the spilled material at the end of the day, Friday, Jan. 9.

EPA treated 62 total vehicles on Friday, Jan. 9.

Throughout the week of Jan. 4, 2026, EPA treated 266 impacted vehicles.

EPA's air monitoring results are online for review.

EPA's surface water monitoring results have also been posted for review.

The Kansas Department of Health and Environment (KDHE) rescinded the stream advisory for the City of Garnett’s stormwater drainage system, which extended to its confluence with Lake Garnett, on Sunday, Jan. 11.

EPA's pH field screening results from the impacted road surface are also online for review.

Questions about impacted vehicles should be directed to Anderson County Emergency Manager Sarah Burkhart at 785-822-8584 or shulcy@andersoncountyks.org.

Questions about EPA’s response operations between Jan. 2 and Jan. 9 should be directed to EPA Region 7 Public Information Officer Kellen Ashford at ashford.kellen@epa.gov.

EPA has ended its no cost car treatment operations to prevent potential human exposure to the spilled material.

EPA treated 62 total vehicles on Friday.

Throughout the week of Jan. 4, 2026, EPA treated 266 impacted vehicles.

EPA's air monitoring results have also been posted for review.

Questions about impacted vehicles should be directed to Anderson County Emergency Manager Sarah Burkhart at 785-822-8584 or shulcy@andersoncountyks.org.

Questions about EPA’s response operations between Jan. 2 and Jan. 9 should be directed to EPA Region 7 Public Information Officer Kellen Ashford at ashford.kellen@epa.gov.

Substance Update:

Additional analytical testing has yielded more information about the spilled substance in Garnett, Kansas. EPA has identified the material as an inorganic, strongly basic, sodium-based compound with a pH of 14 that is very caustic. Substances with a pH of greater than or equal to 12.5 are considered to be hazardous substances.

As a strong base, this sodium-based compound is a reactive chemical. Reactive chemicals undergo various chemical changes when they are exposed to the elements, making the collection of a pure sample for broad-spectrum analysis much more difficult.

Further identification, such as a trade name, will likely require the chemical container or safety data sheet that would be in possession of the party responsible for the spill, which is still part of an ongoing investigation.

EPA treated 51 total vehicles on Thursday. The total number of vehicles treated to date is 204. 

EPA will be ending its car treatment operations at the end of the day, Friday, Jan. 9.

Daily field pH screening and sampling at the outfall at Lake Garnett continued in the inclement weather. To date, there have been no elevated pH levels or detections of concern.

EPA treated 56 total vehicles on Wednesday. The total number of vehicles treated to date is 153. 

Please note that the total number of vehicles treated greater than the originally reported number of 131 as EPA and its contractors are treating vehicles that are stop in for a car treatment unscheduled.

The car treatment is still scheduled to run through Friday, even in the forecasted inclement weather. Work crews will be setting up canopies so they can continue to follow the process outlined in the Frequently Asked Questions.

EPA treated 53 total vehicles on Tuesday. The total number of vehicles treated, to date, is 97 total vehicles (this includes 3 vehicles treated on Sunday as part of the test treatments).

The responding agencies have updated the Frequently Asked Questions. Regarding the spilled substance:

While the trade name of the spilled substance may not be known until a responsible party is identified, the responding agencies characterized the spilled substance from a preliminary field analysis.

EPA Region 7 maintains field portable equipment that can provide information about unknown chemicals that can enable first responders to safely work with unknown materials.

The preliminary field analysis indicates that the substance is a high pH caustic material that has been neutralized with warm, soapy water and a water/vinegar solution.

Based on the field analysis, EPA has enough information to develop response plans; treat residual material; and rule out other characteristics of the spilled material.

This substance is not:

• An acid (low pH)
• An oil or petroleum product
• A halogen, such as chlorine or fluorine
• An oxidizer, such as peroxide
• Flammable
• Volatile
• Radioactive

Positive identification, including the trade name, may require the chemical container or safety data sheet which would be in possession of the party responsible for the spill which is part of an ongoing investigation.

EPA and its contractors performed 41 no cost car treatments on Monday, Jan. 5. Individuals interested in scheduling a time to have their car treated should call 785-822-8584. Please view the car treatment route before arriving for your scheduled treatment time.

EPA, the Kansas Department of Health and Environment (KDHE), the Kansas Department of Transportation (KDOT), the City of Garnett, and Anderson County Emergency Management posted a Frequently Asked Questions. The responding agencies intend to update this FAQ with new questions and answers throughout the response.

An EPA response to material spilled along impacted roadways in Garnett is ongoing. EPA is being assisted by local and state coordinating agencies to help identify the responsible party.

EPA will be establishing a no cost car treatment for individuals whose vehicles were impacted by the unknown, spilled substance.

This car treatment will be available to all impacted individuals at no cost and will operate from 10:00am to 7:00pm on Monday, Jan. 5 through Wednesday, Jan. 7, 2026.