It’s now official: there was no metal contamination in the groundwater on the SEMCORP site. SEMCORP has requested the termination of the suspension of production and commits to regular groundwater testing with results made available for public scrutiny.
Debrecen, Hungary, September 10, 2026 – The laboratory responsible for the March groundwater sampling and testing at SEMCORP’s Debrecen site has formally withdrawn its reports and the accompanying data after concluding that the sampling and testing protocols used were not suitable for the regulatory assessment of metals in groundwater. The withdrawal has been submitted to the competent environmental authority.
The withdrawal provides important new confirmation of the findings of the comprehensive investigation commissioned by SEMCORP following the suspension of its production activities on June 24. That investigation in July and August, involving a team of accredited experts, four independent accredited laboratories, 45 sampling points and hundreds of groundwater and soil samples, found no metals contamination in the groundwater and soil sampled across the site.
Taken together, the laboratory’s formal withdrawal of the March reports and data and the extensive expert site assessment also confirm SEMCORP’s longstanding position that its process and materials are not capable of causing a metal contamination of the nature and magnitude suggested by the March data.
On the basis of this evidence, SEMCORP has submitted a request to the competent authorities to terminate the suspension of its production activities. SEMCORP will resume production only if and when permitted to do so in accordance with all applicable legal requirements.
Groundwater samples taken at SEMCORP’s Debrecen site in March were reported as containing high concentrations of 13 metals, including 12 that SEMCORP does not use. On June 24, the environmental authority suspended the company’s production activities. SEMCORP subsequently commissioned a large-scale investigation to determine whether metals contamination was present, establish what could explain the March figures and provide the authorities with a comprehensive body of evidence.
The central issue with the March report concerns the distinction between total-metal concentrations and dissolved-metal concentrations.
Under the Hungarian regulatory framework applicable to statutory thresholds for groundwater contaminants and generally accepted environmental standards, potential metals contamination is assessed using dissolved-metal concentrations, with soil and other solid particles excluded. Groundwater samples inevitably contain suspended soil particles, and soil naturally contains metals, particularly aluminum and iron. A total-metal analysis can therefore include metals contained in these particles and produce values that cannot properly be compared with regulatory thresholds established for dissolved metals.
The subsequent expert investigation concluded, based on a thorough review of the lab’s sampling and testing records, that the March reports clearly reflected total-metal concentrations rather than the dissolved-metal concentrations required for the relevant groundwater assessment. The laboratory that carried out the March work has confirmed this conclusion, and on that basis has now formally withdrawn its reports.
Other evidence independently supports this conclusion. The March samples showed a pattern of elevated aluminum and iron consistent with the presence of soil particles, and iron is not an input or output material in SEMCORP’s manufacturing process. Controlled testing of the aluminum-containing ceramic materials actually used by SEMCORP was also unable to reproduce anything approaching the extreme March concentrations.
Following the June suspension, SEMCORP commissioned a comprehensive investigation involving a team of accredited experts, four independent accredited laboratories, 45 sampling points and hundreds of groundwater and soil samples. The program was deliberately designed to examine the areas of greatest concern, and samples were taken from 37 newly drilled boreholes as well as eight existing monitoring wells.
The investigation found no contamination by aluminum or the other 12 metals at issue in the groundwater and soil sampled across the site, including around the locations associated with the extreme March figures.
Experts also investigated whether severe contamination could have been present in March but disappeared before the July sampling. Groundwater measurements and modelling indicated that groundwater had moved less than an estimated 10 metres during the relevant period, while soil testing found no evidence that a large quantity of aluminum had simply transferred from groundwater into the soil. The evidence therefore did not support a scenario in which a severe metals contamination event had occurred in March and subsequently disappeared before the July investigation.
Following the laboratory’s formal withdrawal of the March reports and data, and the findings of the comprehensive investigation, SEMCORP has submitted a request to the competent authorities to terminate the suspension of its production activities.
“We respect the government’s responsibility to independently review all of the evidence before making its decision. Production will resume only when suspension has been lifted and all applicable requirements are satisfied,” said James Shih, Managing Director of SEMCORP.
SEMCORP also announced that it will introduce regular groundwater testing at its Debrecen site as part of its long-term environmental monitoring and transparency commitments.
The company intends to invite local NGOs to participate in the samplings, and to make the results available for public scrutiny, following the approach taken with the groundwater metals investigation, for which laboratory reports and supporting information were published so that residents, journalists, independent experts and other interested parties could examine the evidence directly.
“We know that trust cannot be built through statements alone. It has to be supported by evidence and sustained transparency. That is why we will continue regular groundwater monitoring and make the results available for public scrutiny. We want the local community to be able to see the data, not simply take our word for it,” Shih said.
SEMCORP said it remains committed to full cooperation with the environmental authority and other competent authorities. The company also acknowledged that building its relationship with the local community will require continued openness about both its environmental impact and the improvements it is making to its compliance and management systems.
“We understand why the March figures caused serious concern in Debrecen. The laboratory’s withdrawal of its reports and the extensive investigation now provide a clear understanding of what happened. Our responsibility is not only to cooperate fully with the authorities, but also to continue providing the community with evidence it can independently examine. We know that trust must be earned, and we intend to keep working to earn it,” Shih added.
SEMCORP is a global market leader in lithium-ion battery separator films. At its Hungarian site in Debrecen, the company produces advanced separator products that support the manufacture of up to 300,000 vehicles in Europe and the United States annually.
Contact: info@hu.semcorp.com