Trump EPA Takes Action After Uncovering Government Subcontractor Analysts Altering Measurements in East Palestine Train Derailment Clean Up
EPA-Validated Testing Shows No New Groundwater Contamination or Threat to Public Health
WASHINGTON – Today, U.S. Environmental Protection Agency (EPA) sent a notice to Tetra Tech Inc. detailing the failure of its subcontractor—ALS Houston—to meet data quality standards in groundwater sampling conducted at the East Palestine train derailment site in the fall of 2025. Rigorous and ongoing validating analysis confirms there is no ongoing exposure to toxic chemicals from the derailment endangering the public health or environment in East Palestine.
Transparency and gold standard science drive all of EPA’s actions, and the Agency has strict protocols in place to identify inconsistencies, fix problems, and ensure that the public receives accurate health and safety information. In September 2025, as part of this quality assurance and quality control process, EPA identified potential discrepancies in groundwater sampling data from the government’s contractor for 2-butoxyethanol, a colorless solvent used in household cleaners, paints, varnishes, and paint strippers.
With a steadfast commitment to ensuring that the public has accurate and actionable data and information, the Agency immediately launched an investigation. EPA found that the results analyzed by the government subcontractor, ALS Houston, showed the presence of 2-butoxyethanol that did not match the results from split sampling testing at other labs. Under EPA's oversight and after extensive confirmatory testing, in February 2026, EPA’s contractor, Tetra Tech, notified the agency that ALS Houston had in fact altered measurements—which resulted in the false sampling data—and as a result terminated two analysts for failure to follow standard operating procedures. Because of EPA’s investigation and quick action, none of the falsified data was used to make any health, safety, cleanup, or enforcement decisions at the site. Past and current data indicate there is no risk to groundwater from 2-butoxyethanol in East Palestine.
“The Trump EPA has never stopped fighting for the East Palestine community and those impacted by this disaster,” said EPA Administrator Lee Zeldin. “My first trip after being sworn in as EPA Administrator was to visit East Palestine alongside Vice President Vance to speak with community members and see firsthand the devastation the incident has caused. EPA does not stand for analysts altering measurements and we are investigating the actions of this subcontractor to the fullest extent of the law. My team is working swiftly, transparently, and efficiently to redouble all of our efforts to ensure that no one can ever do something like this again.”
EPA has zero tolerance for shortcuts by a lab that could result in inaccurate data and has taken the following actions to remedy this situation:
- Opened an investigation into sampling discrepancies and expanded its own rigorous quality assurance and control process.
- Rejected data submitted by the subcontractor, ALS Houston.
- Referred the data quality issues to EPA’s Office of Inspector General.
- Issued a Cure Notice to the prime contractor along with a review of all active contracts with the subcontractor with an eye towards sample testing and lab analysis.
- Reviewed internal contracting processes to identify institutional controls for the agency’s contract team to ensure this situation does not happen again.
- Updated—and will continue to update—its East Palestine website to ensure that the public has access to the most up-to-date information.
In addition, EPA is considering all avenues for action as the agency takes very seriously the obligations of government contractors to uphold the terms of contracts and applicable laws.
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Background
In September 2025, as soon as the EPA Region 5 office discovered a data discrepancy, the agency opened an investigation. At that time, the agency held all data from ALS Houston and ordered the prime contractor, Tetra Tech, to perform additional data validation on data from August, September, and October.
In December 2025, after finding more discrepancies, the agency sent additional samples to EPA’s PHILIS laboratory. EPA’s testing confirmed there was no 2-butoxyethanol and there was no risk to the public or the environment.
In January 2026, EPA sent additional August-October samples to the PHILIS lab for re-analysis as a double check. All tests at other labs confirmed there was no 2-butoxyethanol in the samples.
As the agency’s investigation continued, in February 2026, Tetra Tech notified EPA that ALS Houston had altered measurements and terminated two data analysts for failing to follow the laboratory’s standard operating procedures. This failure to follow operating procedures resulted in false levels of detection.