Hayden Island, Oregon
© Oregonian/StaffHayden Island.
Federal air monitoring repeatedly detected a poisonous gas on Hayden Island, where residents have complained for months about air pollution so thick they could taste it.

Yet the U.S. Environmental Protection Agency wouldn't answer The Oregonian/OregonLive's request for basic details about the discovery of hydrogen sulfide, a colorless gas that smells like rotten eggs. Nor has the agency informed residents about what it's found.

Judy Smith, a spokeswoman for the U.S. Environmental Protection Agency, would only say the dangerous gas was found at levels high enough to cause reversible short-term health effects like headaches and shortness of breath.

"These are consistent with the complaints from local residents," she said in a written statement.

Smith wouldn't say what concentration of hydrogen sulfide was detected, how frequently it appeared, or where the air monitors were set up during testing conducted from November until January. She said testing results are expected to be released at a May 9 community meeting.

The federal agency's refusal to divulge basic information about its findings continues a series of slow disclosures about Portland's toxic air that have left thousands worried about whether they're breathing clean air.

The Oregon Department of Environmental Quality learned about the discovery on March 25. The agency's new interim director, Peter Shepherd, said officials were told hydrogen sulfide had been detected seven times, most just a few minutes long. Two lasted longer, but Shepherd said the agency was unclear by how much.

He offered far more detail than federal officials, saying some detections had occurred at the Heron Lakes Golf Course, west of an oil refinery being probed. Others were detected with handheld monitors near a sewer manhole, he said.

Shepherd took the reins of the environmental quality agency on April 20 as part of Gov. Kate Brown's effort to improve the state regulator's transparency and public responsiveness. His predecessor left amid criticism of the state's response to air pollution problems connected to glass manufacturers in Portland.

Shepherd said his agency does not know how high the hydrogen sulfide levels were; state officials apparently didn't ask. As the result of The Oregonian/OregonLive's inquiries, Shepherd said he would request the results from the U.S. Environmental Protection Agency.

He also said he had urged the federal agency to release them to the news organization.

At high levels, hydrogen sulfide can kill a person in a single breath. It poses grave dangers to oil refinery crews and sewer workers. Although it can be smelled at very small levels, high volumes in the air can actually paralyze the olfactory nerve in people's noses, leaving them unable to detect dangerous amounts.

The gas can be produced by numerous industrial processes including oil refining as well as the breakdown of sewage.

Since last summer, Hayden Island residents have told state officials they've been smelling a metallic, chemical odor so strong they've awakened at night with headaches, bloody noses and breathing problems that left some reliant on inhalers.

Neighbors say they've been left in the dark about the monitoring results.

"I want answers now," said Mary Lou Putman, a Hayden Island resident who's frequently complained.

"There's a pattern here of withholding important information from the public," she said. "It's extremely concerning to me and all of us who are subjected to the daily spewing."

State and federal regulators are probing two nearby companies that recycle used oil: American Petroleum Environmental Services and the Oil Re-Refining Company. The companies face a May 2 deadline to provide key information.

Neither responded to calls for comment.

Oil Re-Refining has a long history of environmental violations. From 1992 to 2000, the company paid more than $336,000 in fines for hazardous waste and air quality violations, according to state records. It's been fined $138,800 since 2009 by the state.

American Petroleum, meanwhile, was fined $2,400 in 2014 for permit violations.

An Oregon Occupational Safety and Health Administration inspection at American Petroleum in 2015 found low levels of hydrogen sulfide there, but the concentration was well within workplace safety thresholds.

Fedor Zarkhin contributed reporting.