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Proposed Amendment to the National Emission Standards for Hazardous Air Pollutants for Phosphoric Acid Manufacturing

The U.S. Environmental Protection Agency (EPA) is proposing to amend the 2015 National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Phosphoric Acid Manufacturing. On September 6, 2016, PCS Phosphates (now under Nutrien) petitioned EPA to review the 2015 NESHAP based on newly available data. Following analysis of the petitioner’s data, EPA is proposing to revise the mercury standard for calciners in the Phosphoric Acid Manufacturing NESHAP. The proposed amendment will revise the mercury maximum achievable control technology (MACT) floor for existing calciners from 0.14 milligrams per dry standard cubic meter (mg/dscm) at 3-percent oxygen to 0.23 mg/dscm at 3-percent oxygen. We do not anticipate a change in actual mercury emissions as a result of this proposed action given that it is an adjustment to the current baseline of the PCS Phosphates facility in North Carolina. The proposed amendment fulfills EPA’s statutory requirements under the CAA, while maintaining the intent of the emission and operational standards of the 2015 NESHAP. EPA will accept comment on the proposed amendment for 45 days after publication in the Federal Register.

For more information visit the Phosphoric Acid Manufacturing NESHAP rule page

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