Intel secured a milestone state air quality permit Tuesday for a major expansion planned at its chip factories in Hillsboro, but it also received a reprimand from regulators for having significantly understated its Oregon carbon emissions during 2022.

The permit makes way for the upgrade to Intel’s manufacturing campus near Hillsboro Stadium, work the company says represents a “multibillion-dollar” investment. But the reporting gaffe, Intel’s third major air quality issue in Oregon in recent years, raises questions about the reliability of its pollution controls.

Intel applied for a new Oregon air quality permit last year, seeking major increases in its emissions caps for greenhouse gases and other key pollutants. The company plans to build a fourth phase of its D1X research factory at Gordon Moore Park in Hillsboro, a site previously known as Ronler Acres.

The Oregon Department of Environmental Quality awarded Intel that permit on Tuesday. But at the same time, the agency announced that Intel had not accurately reported its emissions of greenhouse gases during 2022.

The company, regulators say, understated its Oregon carbon dioxide emissions by about 155,000 metric tons during 2022. Regulators said the enforcement process for air quality violations is separate from its permitting process, so Intel’s greenhouse gas blunder did not affect its permit application. The state issued Intel a warning letter and Intel said it is “cooperating fully” with the Department of Environmental Quality.

“We take these matters seriously,” Intel spokesperson Elly Akopyan wrote in a statement Tuesday. “Intel notified DEQ of inaccuracies it had discovered in its 2022 Greenhouse Gas emissions data report. Intel is taking steps to address this event and to prevent future similar events.”

Oregon penalized Intel $31,000 last year because the company had inadvertently disconnected pollution control equipment for 63 days, resulting in uncontrolled emissions of hydrogen fluoride, hydrogen chloride and possibly other chemicals.

Intel is Oregon’s largest corporate employer, with 23,000 people working at its Washington County campuses. It’s also the state’s second-largest emitter of greenhouse gases, excluding electric utilities, trailing only Ash Grove Cement Co. in Baker County.

Intel’s new air-quality permit would allow it to triple its annual greenhouse gas emissions, to 1.7 million metric tons.

The Oregon Legislature and Gov. Tina Kotek have awarded Intel $115 million in state funding to pay for its Hillsboro expansion, which the company says will create 2,000 new jobs. Last month, the Biden administration awarded Intel $8.5 billion and billions of dollars’ worth of incentives to subsidize new factories.

On Tuesday, Intel said it is still in the planning stages for the fourth phase of D1X in Hillsboro. The company’s regulatory filings indicate construction could start as soon as next year.