When fully implemented, the rule will result in a reduction of 5,200 tons per year of toxic air pollutants, and 50,000 tons per year of volatile organic compounds (VOCs). Also, as a co-benefit of these final standards, EPA projects that these standards will eliminate emissions of greenhouse gases equivalent to approximately 660,000 tons per year of CO₂.

The EPA estimates the capital cost of this final rule to be approximately $283 million, with an annualized cost of approximately $63 million. The EPA estimates that these final standards will have a negligible impact on the costs of petroleum products.

The action requires continuous monitoring of benzene concentrations at the fenceline of refinery facilities to ensure that refineries appropriately manage toxic emissions. The rule requires corrective action to protect neighboring communities from being exposed to harmful levels of emissions if the established standard level is exceeded. The new fenceline monitors must encircle the facility to detect benzene at very low levels, and the monitoring data will be posted on EPA’s website. In addition, in response to public feedback, the rule provides room for alternative monitoring methods in the future as technology advances.

Other specific requirements in this rule will virtually eliminate visible flare emissions and releases by pressure release devices by requiring a comprehensive program of process changes and pollution prevention measures for these emission sources. It will also require additional emission reductions from storage tanks and delayed coking units, some of which had no previous required controls.

This final rule is based on the risk and technology review of two emissions standards already in place at refineries: the National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries (Refinery MACT 1) and the National Emission Standards for Hazardous Air Pollutants for Petroleum Refineries: Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery Units (Refinery MACT 2).

This rulemaking was informed by a Petroleum Refinery Risk and Technology Review (RTR). During this scientific and technical review, EPA also engaged with key communities in the two years prior to proposing a regulation in 2014.