An estimated 115 gallons of heavy acid spilled inside a North Portland warehouse Tuesday, Aug. 18, after a storage tote's bottom valve ruptured, filling the building with visible vapor and prompting a hazmat response from Portland Fire & Rescue.
All workers inside the facility evacuated safely before crews arrived, the department confirmed. The spill marks the second major acid incident in North Portland in eight days.
Portland Fire & Rescue said on X the 350-gallon tote had lost roughly one-third of its contents through the ruptured valve, allowing free flow of the substance. The department said the speed of the leak before crews arrived was unknown.
The exact chemical was not identified as of Tuesday night. Whether the warehouse's secondary containment systems held, or whether the release reached the ground outside the building, had not been determined.
Eight days earlier on Hayden Island
On Aug. 10, Portland Fire & Rescue hazmat crews responded to a 5,000-gallon tanker truck leaking sulfuric acid on Hayden Island. An estimated 100 gallons entered a storm drain before crews arrived and used sand to dam the flow, according to a Portland Fire & Rescue press release. The Bureau of Environmental Services and the Oregon Department of Environmental Quality were notified. No injuries were reported.
Regulatory thresholds in question
The city's Groundwater Protection Program requires annual hazardous materials reporting for any facility that stores 50 gallons or more of a regulated hazardous substance within the Columbia South Shore and Cascade well fields. Those well fields supply drinking water to more than 800,000 Oregonians. Whether the warehouse falls within the program's geographic boundary, or whether it was enrolled and in compliance, had not been determined as of Tuesday night.
Federal regulations under 40 CFR Part 302 also require immediate reporting of hazardous releases that meet reportable quantities to the Oregon Emergency Response System. Whether the Aug. 18 release met that threshold is unclear.
North Portland's industrial corridors house a heavy concentration of Multnomah County's roughly 1,100 chemical-storing facilities, many along riverfront zones, according to Hoodline, which cited OPB reporting. A 2023 Multnomah County emergency management study flagged toxic spills and vapor inhalation in these areas as a critical priority for evacuation planning, per Oregon Seismic Safety Policy Advisory Commission minutes cited in the same report.
The hazmat response fell to Portland Fire Station 7, which houses the State of Oregon Regional Hazardous Materials Team. The station answers more than 10,000 calls per year and covers all of Portland and Columbia County.
No cleanup timeline or further details on the substance had been released as of Tuesday night. Residents who witness a hazardous material spill can report it to the Oregon Emergency Response System at 800-452-0311.
