Expert Comments on Zenith Energy’s Air Permit Show Major Undercounting of Emissions
By: Audrey Leonard, Staff Attorney
In June, Columbia Riverkeeper submitted technical comments to the Oregon Department of Environmental Quality (DEQ) on Zenith Energy’s draft air quality permit. We hired a technical expert to delve into the calculations that provide the basis of the draft permit. The analysis demonstrates that Zenith will not meet the emissions limits in the permit. In actuality, Zenith’s proposed expansion will increase pollution that is harmful to surrounding neighborhoods and the climate.
Permit History
When Zenith acquired the Portland fuel terminal near the Willamette River in 2017, it inherited an outsized air permit originally designed for asphalt production—an extremely pollution-intensive industry. Now, thanks to the work of environmental and public health advocates, the City of Portland and DEQ are requiring Zenith to obtain permits that are more appropriate for its fuel handling activities. Zenith must bring its fuel storage and transportation emissions of a key pollutant below 40 tons per year, in order to comply with requirements from its Land Use Compatibility Statement from the City of Portland.
Zenith’s Modest Proposal
DEQ released Zenith’s draft air permit for public comment in April 2025. Unfortunately, Zenith’s proposal incorrectly concludes that future emissions will be within the new, reduced limits. From 2022 to 2024, Zenith’s emissions exceeded the limits requested in the new permit. Yet, Zenith claims that it will nearly double its fuel throughput after 2027, add more railcar racks and storage tanks, and operate three new pipelines—all while emitting less than its current operations. This simply does not add up.
What Zenith is proposing is an expansion disguised as a transition to renewable fuels, designed to increase the amount of toxic, flammable fuel transported through our communities and waterways. To get here, Zenith characterizes its emissions using assumptions rooted in the best case scenario rather than reality. Our comments urge DEQ to take a realistic approach to evaluating Zenith’s potential emissions. Doing so necessitates a permit denial due to Zenith’s inability to meet the emissions limits.
Zenith has requested a new permit that would result in fewer state inspections and looser reporting requirements—in exchange for a reduction in allowable emissions compared to Zenith’s current permit. Zenith’s application achieves a “reduction” in emissions on paper, not through any actual changes to its facility or pollution control technology, but by mathematical sleight of hand.
Mathematical Sleight of Hand
Zenith’s new permit was supposed to limit volatile organic compound (VOC) emissions, based on Zenith’s agreement with the City of Portland. VOCs are well known for their adverse effects on public health and the environment. A precursor to ozone, VOCs cause respiratory and other dangerous health effects, even at low levels of exposure. The permit that Zenith proposed appears, on its face, to meet the VOC limit. However, Zenith’s emissions calculations are based on unrealistic assumptions about how much VOC pollution would actually occur. For the following reasons, the draft permit underestimates Zenith’s emissions:
- Emission Factor: Zenith’s calculations rely on a variable that represents the type of facility causing emissions, called an “emission factor.” The draft permit allows Zenith to reclassify its emission factor for the facility—without making any actual changes—resulting in misleadingly low emission totals. The new emission factor Zenith uses is inappropriate for Zenith’s activities, and is based on inadequate data.
- Vapor Pressure: The draft permit assumes a lower-than-realistic vapor pressure for renewable naphtha—one of the fuels that Zenith will handle in increasing amounts. This is important because the vapor pressure of stored fuels significantly influences the rate and amount of emissions.
- Loading Emissions: The draft permit underestimates emissions from loading fuel to and from marine vessels, rail cars, and storage tanks. Zenith relies on an unsupported assumption that all of the equipment used will be “leak free and vapor tight.”
Realistic estimates for any one of these elements put Zenith above the VOC emission limits for this type of permit, and above the limits Zenith negotiated with the City of Portland. Rather than accept Zenith’s mathematical sleight of hand as truth, DEQ should deny Zenith’s permit.