Milky Spill in Goose Creek Kills Fish, Probe Ongoing

Officials investigate a milky white spill in Goose Creek, West Chester, traced to Atmos Technologies.

Published on Mar. 5, 2026

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An investigation continues in Chester County, Pennsylvania, after a 'milky white substance' entered Goose Creek, affecting waterways in West Chester and West Goshen. The Pennsylvania Department of Environmental Protection (DEP) traced the discharge to Atmos Technologies, a company that produces a manufactured product called 'AC-645' used in environmental remediation cleanups. Officials confirmed that a large number of fish died after the substance entered the creek, and authorities warned residents to stay out of the water.

Why it matters

The incident highlights the potential environmental impact of industrial discharges and the importance of strict regulations and oversight to protect local waterways and wildlife. It also raises questions about the safety and proper handling of chemicals used in environmental remediation efforts.

The details

The incident began around 12:20 p.m. Saturday when West Chester Borough received a report about the unusual liquid appearing in the creek. Environmental officials soon traced the source to an outfall pipe on the 200 block of Garfield Avenue connected to Atmos Technologies' facility. The company later identified the substance as a manufactured product called 'AC-645' or 'Long Duration Foam AC-645' used in environmental remediation cleanups. Atmos claimed the product is nonhazardous, non-toxic, and fully biodegradable, but the spill resulted in a large number of fish deaths.

  • The incident began around 12:20 p.m. on Saturday, March 5, 2026.
  • By about 12:45 p.m. on Saturday, the source had been identified and the outfall pipe was plugged by the DEP and West Chester Borough.
  • DEP personnel were on-site on Sunday, March 6, and Monday, March 7, and reported clear conditions in the creek.
  • DEP teams visited Goose Creek on Wednesday, March 9, and reported that the waterway appeared clear, though foam remained on debris in the creek.
  • As of Wednesday morning, March 9, officials reported no additional fish kills downstream.

The players

Atmos Technologies

A company that produces a manufactured product called 'AC-645' or 'Long Duration Foam AC-645' used in environmental remediation cleanups. The company's facility in West Chester was the source of the milky white substance that entered Goose Creek.

Pennsylvania Department of Environmental Protection (DEP)

The state agency that traced the discharge to Atmos Technologies, is supervising the cleanup operations, and is monitoring the downstream flow of Goose Creek.

West Chester Borough

The local government that received the initial report about the unusual liquid in Goose Creek and worked with the DEP to plug the outfall pipe.

Goose Creek Alliance

A local environmental advocacy group that plans to seek penalties connected to the incident and is requesting a legally enforceable restoration plan for the creek.

Fred Rullo

The CEO of Atmos Technologies, who stated that the company's priority is the protection of the environment and the community, and that they are cooperating with officials during the investigation.

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What they’re saying

“The product itself is nonhazardous, non-toxic, and fully biodegradable.”

— Atmos Technologies (southphillyreview.com)

“Our priority is the protection of the environment and the community in which we operate. We are taking this incident seriously and are conducting a full investigation to address the issue.”

— Fred Rullo, CEO of Atmos Technologies (southphillyreview.com)

What’s next

Several agencies, including the DEP, West Chester Borough, West Goshen officials, the Chester County Hazardous Materials Response Team, and the Pennsylvania Fish and Boat Commission, are continuing to investigate the cause of the leak and monitor the downstream flow of Goose Creek. The Goose Creek Alliance is also planning to seek penalties and request a legally enforceable restoration plan for the creek.

The takeaway

This incident highlights the importance of strict regulations and oversight to protect local waterways and wildlife from the potential environmental impacts of industrial discharges, even when the companies claim their products are 'nonhazardous, non-toxic, and fully biodegradable.' It also raises questions about the proper handling and disposal of chemicals used in environmental remediation efforts.