(a) You are subject to this subpart if you own or operate an HCl production facility that produces a liquid HCl product at a concentration of 30 weight percent or greater during its normal operations and is located at, or is part of, a major source of HAP. This does not include HCl production facilities that only produce occasionally liquid HCl product at a concentration of 30 weight percent or greater.

(1) An HCl production facility is the collection of unit operations and equipment associated with the production of liquid HCl product. The HCl production facility begins at the point where a gaseous stream containing HCl enters the HCl production unit. The HCl production facility includes all HCl storage tanks that contain liquid HCl product that is produced in the HCl production unit, with the exceptions noted in paragraph (a)(2) of this section. The HCl production facility also includes all HCl transfer operations that load HCl product produced in the HCl production unit into a tank truck, rail car, ship, or barge, along with the piping and other equipment in HCl service used to transfer liquid HCl product from the HCl production unit to the HCl storage tanks and/or HCl transfer operations. The HCl production facility ends at the point that the liquid HCl product produced in the HCl production unit is loaded into a tank truck, rail car, ship, or barge, at the point the HCl product enters another process on the plant site, or at the point the HCl product leaves the plant site via pipeline.

(2) Storage tanks that are dedicated feedstock tanks for another process and storage tanks that store HCl dedicated for use in wastewater treatment are not considered part of an HCl production facility.

(3) A major source of HAP emissions is any stationary source or group of stationary sources within a contiguous area under common control that emits or has the potential to emit any single HAP at a rate of 9.07 megagrams (10 tons) or more per year or any combination of HAP at a rate of 22.68 megagrams (25 tons) or more per year.

(b) An HCl production facility is not subject to this subpart if it is also subject to NESHAP under one of the subparts listed in paragraphs (b)(1) through (5) of this section.

(1) 40 CFR part 63, subpart S, National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry.

(2) 40 CFR part 63, subpart CCC, National Emission Standards for Hazardous Air Pollutants for Steel Pickling—HCl Process Facilities and Hydrochloric Acid Regeneration Plants.

(3) 40 CFR part 63, subpart MMM, National Emission Standards for Hazardous Air Pollutants for Pesticide Active Ingredient Production.

(4) 40 CFR part 63, section 63.994, subpart SS, National Emission Standards for Closed Vent Systems, Control Devices, Recovery Devices and Routing to a Fuel Gas System or a Process.

(5) 40 CFR part 63, subpart GGG, National Emission Standards for Pharmaceuticals Production.

(c) An HCl production facility is not subject to this subpart if it is located following the incineration of chlorinated waste gas streams, waste liquids, or solid wastes, and the emissions from the HCl production facility are subject to section 63.113(c), subpart G, National Emission Standards for Organic Hazardous Air Pollutants from the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater.

(d) An HCl production facility is not subject to this subpart if it produces HCl through the direct synthesis of hydrogen and chlorine and is part of a chlor-alkali facility.

(e) An HCl production facility is not subject to this subpart if it is a research and development facility.

(f) An HCl production facility is not subject to this subpart if all of the gaseous streams containing HCl and chlorine (Cl2) from HCl process vents, HCl storage tanks, and HCl transfer operations are recycled or routed to another process for process purpose, prior to being discharged to the atmosphere.