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10 US refineries exceeded federal benzene levels at their perimeters

Two other facilities surpassed limit but then lowered their emissions as required

by Cheryl Hogue
February 10, 2020

Photo of a chain-link fence with a sign saying private property, no trespassing, and violators will be prosecuted.
Credit: Shutterstock
Refineries must act to lower benzene emissions if they exceed a yearly average of 9 µm of benzen per m3 at their perimeters.

Federal data show that last year, 10 US refineries exceeded the Environmental Protection Agency’s action level for benzene, an advocacy group announced in early February. That is the concentration at which refineries must cut emissions of carcinogenic benzene.

The refineries—six in Texas and one each in Louisiana, New Mexico, Mississippi, and Pennsylvania—all surpassed a yearly average of 9 µg of benzene per m3 of air at their perimeters. More than 30,000 people live within 1.6 km of those 10 facilities, the Environmental Integrity Project, a group that advocates for enforcement of environmental laws, says in a report that analyzes monitoring data submitted to EPA.

As part of a Clean Air Act regulation that took effect in 2018, refineries that exceed the EPA’s action threshold must determine where their benzene is coming from and then act to lower concentrations at their perimeters. The Environmental Integrity Project and the activist law firm Earthjustice successfully sued the EPA to issue that so-called fence-line regulation to protect the health of people living close to refineries. Benzene is a known human carcinogen that is also linked to blood disorders, reproductive effects, and adverse developmental effects, according to the EPA.

The benzene monitoring rule appears to be working in some cases. The report notes that two refineries—in addition to the other 10—surpassed the 9 µg/m3 threshold for much of 2019. But those two took action that lowered their fence-line benzene concentrations later that year.

Eric Schaeffer, executive director of the Environmental Integrity Project, says state agencies or the EPA are empowered to take action against facilities that do not follow the regulation’s requirements.

American Petroleum Institute spokesperson Scott Lauermann says, “The fence-line monitoring program provides refiners with an additional tool to manage and control emission sources, but as the EPA notes, it is not intended to measure community benzene levels, nor is the action level representative of any health-based standard. Because fence-line monitors capture benzene emissions from all nearby sources, the data may at times reflect emissions from external sources and events, such as wildfires and neighboring facilities.”



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