Subpart G Information Sheet
Overview
Subpart G of the Greenhouse Gas Reporting Program (GHGRP) (40 CFR 98.70 – 98.78) applies to any facility that contains an ammonia (NH3) manufacturing process and meets the Subpart G source category definition. Some subparts have thresholds that determine applicability for reporting, and some do not. To decide whether your facility must report under this subpart, please refer to 40 CFR 98.71 and the GHGRP Applicability Tool.
This Information Sheet is intended to help facilities reporting under Subpart G understand how the source category is defined, what greenhouse gases (GHGs) must be reported, how GHG emissions must be calculated and shared with EPA, and where to find more information.
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- How is This Source Category Defined?
- What GHGs Must Be Reported?
- How Must GHG Emissions Be Calculated?
- What Information Must Be Reported?
- What Records Must Be Maintained?
- When and How Must Reported Be Submitted?
- When Can a Facility Stop Reporting?
- For More Information
How is This Source Category Defined?
The ammonia (NH3) manufacturing source category consists of process units in which NH3 is manufactured either from a fossil-based feedstock produced via steam reforming of a hydrocarbon (HC) or through the gasification of solid and liquid raw material.
What GHGs Must Be Reported?
NH3 manufacturing facilities must report the following emissions:
- Carbon dioxide (CO2) process emissions for each NH3 manufacturing process unit following the requirements of this subpart (CO2 process emissions reported under this subpart may include CO2 that is later consumed on site for urea (CO(NH2)2) production, and therefore is not released to the ambient air from the NH3 manufacturing process unit).
- CO2, methane (CH4), and nitrous oxide (N2O) emissions from each stationary combustion unit. Report these emissions under Subpart C (General Stationary Fuel Combustion Sources) found at 40 CFR §§ 98.30 – 98.38, except that for NH3 manufacturing processes Subpart C does not apply to any CO2 resulting from combustion of the waste recycle stream (commonly referred to as the purge gas stream).
- CO2 emissions collected and transferred off site, following the requirements of Subpart PP (Suppliers of CO2) found at 40 CFR §§ 98.420 – 98.428.
If multiple Greenhouse Gas Reporting Program (GHGRP) source categories are co-located at a facility, the facility may need to report GHG emissions under a different subpart. Please refer to the relevant information sheet for a summary of the rule requirements and emissions calculation and reporting requirements for any other applicable source categories located at the facility.
How Must GHG Emissions Be Calculated?
Reporters must calculate and report process CO2 emissions from each NH3 manufacturing process unit by using one of two methods:
- Installing and operating a continuous emission monitoring system (CEMS) to measure combined process and combustion CO2 emissions according to the requirements specified in 40 CFR Part 98, Subpart C.
- Calculating CO2 process emissions using the equations provided in the rule for solid, liquid, and gaseous feedstocks, as applicable, along with the following measurements:
- Continuous measurement of gaseous or liquid feedstock consumed (using a flow meter).
- Monthly aggregate of solid feedstock consumed (using company records).
- Carbon content and average molecular weight of each feedstock consumed (using reports from your supplier).
However, if process CO2 emissions from an NH3 manufacturing process unit are vented through the same stack as any combustion unit or process equipment that reports CO2 emissions using a CEMS that complies with the Tier 4 calculation methodology in Subpart, then the owner or operator must report under Subpart G, the combined stack emissions from that stack, instead of using the calculation procedures described above.
A checklist for data that must be monitored is available here: Subpart G Monitoring Checklist.
What Information Must Be Reported?
In addition to the information required by the General Provisions in Subpart A, found at 40 CFR § 98.3(c), the following must be reported under the circumstances indicated:
- If a CEMS is used to measure CO2 emissions, under Subpart G report the relevant information required by 40 CFR § 98.33(a)(4)), Subpart C for the Tier 4 calculation methodology and the following information:
- Annual quantity of each type of feedstock consumed for NH3 manufacturing (standard cubic feet (scf) of gaseous feedstock or gallons (gal) of liquid feedstock or kilograms (kg) of solid feedstock).
- Method used for determining quantity of feedstock used.
- Annual NH3 production (metric tons), sum of all process units reported within Subpart G).
- If a CEMS is not used to measure emissions, report the following information for each unit:
- Annual CO2 process emissions (metric tons) for each NH3 manufacturing process unit.
- Annual quantity of each type of feedstock consumed for NH3 manufacturing (scf of gaseous feedstock or gal of liquid feedstock or kg of solid feedstock).
- Method used for determining quantity of monthly feedstock used.
- Whether monthly carbon content for each feedstock is based on reports from the supplier or analysis of carbon content.
- If monthly carbon content of feedstock is based on analysis, the test method used.
- Sampling analysis results of carbon content of feedstock as determined for quality assurance/quality control (QA/QC) of supplier data under 40 CFR § 98.74(e).
- Annual average carbon content of each type of feedstock consumed.
- Annual CO(NH2)2 production (metric tons) and method used to determine CO(NH2)2 production.
- Annual CO2 emissions (metric tons) from the steam reforming of a HC or the gasification of solid and liquid raw material at the NH3 manufacturing process unit used to produce CO(NH2)2 and the method used to determine the CO2 consumed in CO(NH2)2 production.
- Annual NH3 production (metric tons, sum of all process units reported within Subpart G).
- Annual quantity of methanol (CH3OH) intentionally produced as a desired product, for each process unit (metric tons).
What Records Must Be Maintained?
Reporters are required to retain records that pertain to their annual GHGRP report for at least three years after the date the report is submitted. Please see the Subpart A Information Sheet and 40 CFR § 98.3(g) for general recordkeeping requirements. Specific recordkeeping requirements for Subpart G are listed at 40 CFR § 98.77.
When and How Must Reports Be Submitted?
Reporters must submit their annual GHGRP reports for the previous calendar year to the EPA by March 31st, unless the 31st falls on a Saturday, Sunday, or federal holiday, in which case reports are due on the next business day. Annual reports must be submitted electronically using the electronic Greenhouse Gas Reporting Tool (e-GGRT), the GHGRP’s online reporting system.
Additional information on setting up user accounts, registering a facility, and submitting annual reports is available on the GHGRP Help webpage.
When Can a Facility Stop Reporting?
A facility may discontinue reporting under several scenarios, which are summarized in the Subpart A Information Sheet and the frequently asked questions (FAQs).
For More Information
For additional information on Subpart G, please visit the Subpart G webpage. For additional information on the GHGRP, please visit the GHGRP website, which includes additional information sheets, data previously reported to the GHGRP, training materials, and links to FAQs. For questions that cannot be answered through the GHGRP website, please contact us at: GHGreporting@epa.gov.
This Information Sheet is provided solely for informational purposes. It does not replace the need to read and comply with the regulatory text contained in the rule. Rather, it is intended to help reporting facilities and suppliers understand key provisions of the GHGRP. It does not provide legal advice; have a legally binding effect; or expressly or implicitly create, expand, or limit any legal rights, obligations, responsibilities, expectations, or benefits with regard to any person or entity.
Archived Versions
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