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Subpart PP—Suppliers of Carbon Dioxide

§ 98.420 Definition of the source category.

(a) The carbon dioxide (CO2) supplier source category consists of the following:

(1) Facilities with production process units that capture a CO2 stream for purposes of 

supplying CO2 for commercial applications or that capture and maintain custody of a CO2 stream 

in order to sequester or otherwise inject it underground. Capture refers to the initial separation 

and removal of CO2 from a manufacturing process or any other process.

(2) Facilities with CO2 production wells that extract or produce a CO2 stream for 

purposes of supplying CO2 for commercial applications or that extract and maintain custody of a 

CO2 stream in order to sequester or otherwise inject it underground.

(3) Importers or exporters of bulk CO2.

(b) This source category is focused on upstream supply. It does not cover:

(1) Storage of CO2 above ground or in geologic formations.

(2) Use of CO2 in enhanced oil and gas recovery.

(3) Transportation or distribution of CO2.

(4) Purification, compression, or processing of CO2.

(5) On-site use of CO2 captured on site.

(c) This source category does not include CO2 imported or exported in equipment, such 

as fire extinguishers.

§ 98.421 Reporting threshold.

Any supplier of CO2 who meets the requirements of § 98.2(a)(4) of subpart A of this part 

must report the mass of CO2 captured, extracted, imported, or exported.

§ 98.422 GHGs to report.
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(a) Mass of CO2 captured from production process units.

(b) Mass of CO2 extracted from CO2 production wells.

(c) Mass of CO2 imported.

(d) Mass of CO2 exported.

§ 98.423 Calculating CO2 supply.

(a) Except as allowed in paragraph (b) of this section, calculate the annual mass of CO2

captured, extracted, imported, or exported through each flow meter in accordance with the 

procedures specified in either paragraph (a)(1) or (a)(2) of this section. If multiple flow meters 

are used, you shall calculate the annual mass of CO2 for all flow meters according to the 

procedures specified in paragraph (a)(3) of this section.

(1) For each mass flow meter, you shall calculate quarterly the mass of CO2 in a CO2

stream in metric tons by multiplying the mass flow by the composition data, according to 

Equation PP-1 of this section. Mass flow and composition data measurements shall be made in 

accordance with § 98.424 of this subpart.

Where:

CO2,u = Annual mass of CO2 (metric tons) through flow meter u.

CCO2,p,u = Quarterly CO2 concentration measurement in flow for flow meter u in quarter 

p (wt. %CO2).

Qp,u = Quarterly mass flow rate measurement for flow meter u in quarter p (metric 

tons).

p = Quarter of the year.

u = Flow meter.
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(2) For each volumetric flow meter, you shall calculate quarterly the mass of CO2 in a 

CO2 stream in metric tons by multiplying the volumetric flow by the concentration and density

data, according to Equation PP-2 of this section. Volumetric flow, concentration and density data 

measurements shall be made in accordance with § 98.424 of this section.

Where:

CO2,u = Annual mass of CO2 (metric tons) through flow meter u.

CCO2,p = Quarterly CO2 concentration measurement in flow for flow meter u in quarter 

p (measured as either volume % CO2 or weight % CO2).

Qp = Quarterly volumetric flow rate measurement for flow meter u in quarter p 

(standard cubic meters).

Dp = Density of CO2 in quarter p (metric tons CO2 per standard cubic meter) for 

flow meter u if CCO2,p is measured as volume % CO2, or density of the whole 

CO2 stream for flow meter u (metric tons per standard cubic meter) if CCO2,p

is measured as weight % CO2.

p = Quarter of the year.

u = Flow meter.

(3) To aggregate data, use either Equation PP-3a or PP-3b in this paragraph, as 

appropriate.

(i) For facilities with production process units or production wells that capture or extract 

a CO2 stream and either measure it after segregation or do not segregate the flow, calculate the 

total CO2 supplied in accordance with Equation PP-3a in paragraph (a)(3).

where:

CO2 = Total annual mass of CO2 (metric tons).
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CO2,u = Annual mass of CO2 (metric tons) through flow meter u.

u = Flow meter.

(ii) For facilities with production process units that capture a CO2 stream and measure it 

ahead of segregation, calculate the total CO2 supplied in accordance with Equation PP-3b.

where:

CO2 = Total annual mass of CO2 (metric tons).

CO2,u = Annual mass of CO2 (metric tons) through main flow meter u.

CO2,v = Annual mass of CO2 (metric tons) through subsequent flow meter v for use 

on site.

u = Main flow meter.

v = Subsequent flow meter.

(b) As an alternative to paragraphs (a)(1) through (3) of this section for CO2 that is 

supplied in containers, calculate the annual mass of CO2 supplied in containers delivered by each 

CO2 stream in accordance with the procedures specified in either paragraph (b)(1) or (b)(2) of 

this section. If multiple CO2 streams are used to deliver CO2 to containers, you shall calculate the 

annual mass of CO2 supplied in containers delivered by all CO2 streams according to the 

procedures specified in paragraph (b)(3) of this section.

(1) For each CO2 stream that delivers CO2 to containers, for which mass is measured, you 

shall calculate CO2 supply in containers using Equation PP-1 of this section.

where:

CO2,u = Annual mass of CO2 (metric tons) supplied in containers delivered by CO2

stream u.

CCO2,p,u = Quarterly CO2 concentration measurement of CO2 stream u that delivers CO2

to containers in quarter p (wt. %CO2).
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Qp,u = Quarterly mass of contents supplied in all containers delivered by CO2 stream 

u in quarter p (metric tons).

p = Quarter of the year.

u = CO2 stream that delivers to containers.

(2) For each CO2 stream that delivers to containers, for which volume is measured, you 

shall calculate CO2 supply in containers using Equation PP-2 of this section.

where:

CO2,u = Annual mass of CO2 (metric tons) supplied in containers delivered by CO2

stream u.

CCO2,p = Quarterly CO2 concentration measurement of CO2 stream u that delivers CO2

to containers in quarter p (measured as either volume % CO2 or weight % 

CO2).

Qp = Quarterly volume of contents supplied in all containers delivered by CO2

stream u in quarter p (standard cubic meters).

Dp = Quarterly CO2 density determination for CO2 stream u in quarter p (metric 

tons per standard cubic meter) if CO2,p is measured as volume % CO2, or 

density of CO2 stream u (metric tons per standard cubic meter) if CO2,p is 

measured as weight % CO2.

p = Quarter of the year.

u = CO2 stream that delivers to containers.

(3) To aggregate data, sum the mass of CO2 supplied in containers delivered by all CO2

streams in accordance with Equation PP-3a of this section.

where:

CO2 = Annual mass of CO2 (metric tons) supplied in containers delivered by all CO2

streams.

CO2,u = Annual mass of CO2 (metric tons) supplied in containers delivered by CO2

stream u.

u = CO2 stream that delivers to containers.
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(c) Importers or exporters that import or export CO2 in containers shall calculate the total 

mass of CO2 imported or exported in metric tons based on summing the mass in each CO2

container using weigh bills, scales, or load cells according to Equation PP-4 of this section.

where:

CO2 = Annual mass of CO2 (metric tons).

Q = Annual mass in all CO2 containers imported or exported during the reporting 

year (metric tons).

§ 98.424 Monitoring and QA/QC requirements.

(a) Determination of quantity. (1) Reporters following the procedures in § 98.423(a) shall 

determine quantity using a flow meter or meters located in accordance with this paragraph.

(i) If the CO2 stream is segregated such that only a portion is captured for commercial 

application or for injection, you must locate the flow meter according to the following:

(A) For reporters following the procedures in § 98.423(a)(3)(i), you must locate the flow 

meter(s) after the point of segregation.

(B) For reporters following the procedures in paragraph (a)(3)(ii) of § 98.423, you must 

locate the main flow meter(s) on the captured CO2 stream(s) prior to the point of segregation and 

the subsequent flow meter(s) on the CO2 stream(s) for on-site use after the point of segregation. 

You may only follow the procedures in paragraph (a)(3)(ii) of § 98.423 if the CO2 stream(s) for 

on-site use is/are the only diversion(s) from the main, captured CO2 stream(s) after the main flow 

meter location(s).

(ii) Reporters that have a mass flow meter or volumetric flow meter installed to measure 

the flow of a CO2 stream that meets the requirements of paragraph (a)(1)(i) of this section shall 
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base calculations in § 98.423 of this subpart on the installed mass flow or volumetric flow 

meters.

(iii) Reporters that do not have a mass flow meter or volumetric flow meter installed to 

measure the flow of the CO2 stream that meets the requirements of paragraph (a)(1)(i) of this 

section shall base calculations in § 98.423 of this subpart on the flow of gas transferred off site 

using a mass flow meter or a volumetric flow meter located at the point of off-site transfer.

(2) Reporters following the procedures in paragraph (b) of § 98.423 shall determine 

quantity in accordance with this paragraph.

(i) Reporters that supply CO2 in containers using weigh bills, scales, or load cells shall 

measure the mass of contents of each CO2 container to which the CO2 stream is delivered, sum 

the mass of contents supplied in all containers to which the CO2 stream is delivered during each 

quarter, sample the CO2 stream delivering CO2 to containers on a quarterly basis to determine the 

composition of the CO2 stream, and apply Equation PP-1.

(ii) Reporters that supply CO2 in containers using loaded container volumes shall 

measure the volume of contents of each CO2 container to which the CO2 stream is delivered, sum 

the volume of contents supplied in all containers to which the CO2 stream is delivered during 

each quarter, sample the CO2 stream on a quarterly basis to determine the composition of the 

CO2 stream, determine the density quarterly, and apply Equation PP-2.

(3) Importers or exporters that import or export CO2 in containers shall measure the mass 

in each CO2 container using weigh bills, scales, or load cells and sum the mass in all containers 

imported or exported during the reporting year.

(4) All flow meters, scales, and load cells used to measure quantities that are reported in § 

98.423 of this subpart shall be operated and calibrated according to the following procedure:
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(i) You shall use an appropriate standard method published by a consensus-based 

standards organization if such a method exists. Consensus-based standards organizations include, 

but are not limited to, the following: ASTM International, the American National Standards 

Institute (ANSI), the American Gas Association (AGA), the American Society of Mechanical 

Engineers (ASME), the American Petroleum Institute (API), and the North American Energy

Standards Board (NAESB).

(ii) Where no appropriate standard method developed by a consensus-based standards 

organization exists, you shall follow industry standard practices.

(iii) You must ensure that any flow meter calibrations performed are NIST traceable.

(5) Reporters using Equation PP-2 of this subpart and measuring CO2 concentration as

weight % CO2 shall determine the density of the CO2 stream on a quarterly basis in order to 

calculate the mass of the CO2 stream according to one of the following procedures:

(i) You may use a method published by a consensus-based standards organization. 

Consensus-based standards organizations include, but are not limited to, the following: ASTM 

International (100 Barr Harbor Drive, P.O. Box CB700, West Conshohocken, Pennsylvania 

19428-B2959, (800) 262-1373, http://www.astm.org), the American National Standards Institute 

(ANSI, 1819 L Street, NW., 6th floor, Washington, DC 20036, (202) 293-8020, 

http://www.ansi.org), the American Gas Association (AGA, 400 North Capitol Street, NW., 4th 

Floor, Washington, DC 20001, (202) 824-7000, http://www.aga.org), the American Society of 

Mechanical Engineers (ASME, Three Park Avenue, New York, NY 10016-5990, (800) 843-

2763, http://www.asme.org), the American Petroleum Institute (API, 1220 L Street, NW., 

Washington, DC 20005-4070, (202) 682-8000, http://www.api.org), and the North American 

Energy Standards Board (NAESB, 801 Travis Street, Suite 1675, Houston, TX 77002, (713) 
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356-0060, http://www.api.org). The method(s) used shall be documented in the Monitoring Plan 

required under § 98.3(g)(5).

(ii) You may follow an industry standard method.

(b) Determination of concentration. (1) Reporters using Equation PP-1 or PP-2 of this 

subpart shall sample the CO2 stream on a quarterly basis to determine the composition of the 

CO2 stream.

(2) Methods to measure the composition of the CO2 stream must conform to applicable 

chemical analytical standards. Acceptable methods include, but are not limited to, the U.S. Food 

and Drug Administration food-grade specifications for CO2 (see 21 CFR 184.1240) and ASTM 

standard E1747-95 (Reapproved 2005) Standard Guide for Purity of Carbon Dioxide Used in 

Supercritical Fluid Applications (ASTM International, 100 Barr Harbor Drive, P.O. Box CB700, 

West Conshohocken, Pennsylvania 19428-B2959, (800) 262-1373, http://www.astm.org).

(c) You shall convert the density of the CO2 stream(s) and all measured volumes of 

carbon dioxide to the following standard industry temperature and pressure conditions: Standard 

cubic meters at a temperature of 60 degrees Fahrenheit and at an absolute pressure of 1 

atmosphere. If you apply the density value for CO2 at standard conditions, you must use 

0.001868 metric tons per standard cubic meter.

§ 98.425 Procedures for estimating missing data.

(a) Whenever the quality assurance procedures in § 98.424(a)(1) of this subpart cannot be 

followed to measure quarterly mass flow or volumetric flow of CO2, the most appropriate of the 

following missing data procedures shall be followed:

(1) A quarterly CO2 mass flow or volumetric flow value that is missing may be 

substituted with a quarterly value measured during another quarter of the current reporting year.
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(2) A quarterly CO2 mass flow or volumetric flow value that is missing may be 

substituted with a quarterly value measured during the same quarter from the past reporting year.

(3) If a mass or volumetric flow meter is installed to measure the CO2 stream, you may

substitute data from a mass or volumetric flow meter measuring the CO2 stream transferred for 

any period during which the installed meter is inoperable.

(4) The mass or volumetric flow used for purposes of product tracking and billing 

according to the reporter's established procedures may be substituted for any period during which 

measurement equipment is inoperable.

(b) Whenever the quality assurance procedures in § 98.424(b) of this subpart cannot be 

followed to determine concentration of the CO2 stream, the most appropriate of the following 

missing data procedures shall be followed:

(1) A quarterly concentration value that is missing may be substituted with a quarterly

value measured during another quarter of the current reporting year.

(2) A quarterly concentration value that is missing may be substituted with a quarterly 

value measured during the same quarter from the previous reporting year.

(3) The concentration used for purposes of product tracking and billing according to the 

reporter's established procedures may be substituted for any quarterly value.

(c) Missing data on density of the CO2 stream shall be substituted with quarterly or 

annual average values from the previous calendar year.

(d) Whenever the quality assurance procedures in § 98.424(a)(2) of this subpart cannot be 

followed to measure quarterly quantity of CO2 in containers, the most appropriate of the 

following missing data procedures shall be followed:
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(1) A quarterly quantity of CO2 in containers that is missing may be substituted with a 

quarterly value measured during another representative quarter of the current reporting year.

(2) A quarterly quantity of CO2 in containers that is missing may be substituted with a 

quarterly value measured during the same quarter from the past reporting year.

(3) The quarterly quantity of CO2 in containers recorded for purposes of product tracking 

and billing according to the reporter's established procedures may be substituted for any period 

during which measurement equipment is inoperable.

§ 98.426 Data reporting requirements.

In addition to the information required by § 98.3(c) of subpart A of this part, the annual 

report shall contain the following information, as applicable:

(a) If you use Equation PP-1 of this subpart, report the following information for each 

mass flow meter or CO2 stream that delivers CO2 to containers:

(1) Annual mass in metric tons of CO2.

(2) Quarterly mass in metric tons of CO2.

(3) Quarterly concentration of the CO2 stream.

(4) The standard used to measure CO2 concentration.

(5) The location of the flow meter in your process chain in relation to the points of CO2

stream capture, dehydration, compression, and other processing.

(b) If you use Equation PP-2 of this subpart, report the following information for each 

volumetric flow meter or CO2 stream that delivers CO2 to containers:

(1) Annual mass in metric tons of CO2.

(2) Quarterly volume in standard cubic meters of CO2.

(3) Quarterly concentration of the CO2 stream in volume or weight percent.
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(4) Report density as follows:

(i) Quarterly density of the CO2 stream in metric tons per standard cubic meter if you 

report the concentration of the CO2 stream in paragraph (b)(3) of this section in weight percent.

(ii) Quarterly density of CO2 in metric tons per standard cubic meter if you report the 

concentration of the CO2 stream in paragraph (b)(3) of this section in volume percent.

(5) The method used to measure density.

(6) The standard used to measure CO2 concentration.

(7) The location of the flow meter in your process chain in relation to the points of CO2

stream capture, dehydration, compression, and other processing.

(c) For the aggregated annual mass of CO2 emissions calculated using Equation PP-3a or 

PP-3b, report the following:

(1) If you use Equation PP-3a of this subpart, report the annual CO2 mass in metric tons 

from all flow meters and CO2 streams that deliver CO2 to containers.

(2) If you use Equation PP-3b of this subpart, report:

(i) The total annual CO2 mass through main flow meter(s) in metric tons.

(ii) The total annual CO2 mass through subsequent flow meter(s) in metric tons.

(iii) The total annual CO2 mass supplied in metric tons.

(iv) The location of each flow meter in relation to the point of segregation.

(d) If you use Equation PP-4 of this subpart, report at the corporate level the annual mass 

of CO2 in metric tons in all CO2 containers that are imported or exported.

(e) Each reporter shall report the following information:

(1) The type of equipment used to measure the total flow of the CO2 stream or the total 

mass or volume in CO2 containers.
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(2) The standard used to operate and calibrate the equipment reported in (e)(1) of this 

section.

(3) The number of days in the reporting year for which substitute data procedures were 

used for the following purpose:

(i) To measure quantity.

(ii) To measure concentration.

(iii) To measure density.

(f) Report the aggregated annual quantity of CO2 in metric tons that is transferred to each 

of the following end use applications, if known:

(1) Food and beverage.

(2) Industrial and municipal water/wastewater treatment.

(3) Metal fabrication, including welding and cutting.

(4) Greenhouse uses for plant growth.

(5) Fumigants (e.g., grain storage) and herbicides.

(6) Pulp and paper.

(7) Cleaning and solvent use.

(8) Fire fighting.

(9) Transportation and storage of explosives.

(10) Injection of carbon dioxide for enhanced oil and natural gas recovery that is covered 

by subpart UU of this part.

(11) Geologic sequestration of carbon dioxide that is covered by subpart RR of this part.

(12) Research and development.

(13) Other.
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(g) Each production process unit that captures a CO2 stream for purposes of supplying 

CO2 for commercial applications or in order to sequester or otherwise inject it underground when 

custody of the CO2 is maintained shall report the percentage of that stream, if any, that is 

biomass-based during the reporting year.

§ 98.427 Records that must be retained.

In addition to the records required by § 98.3(g) of subpart A of this part, you must retain 

the records specified in paragraphs (a) through (c) of this section, as applicable.

(a) The owner or operator of a facility containing production process units must retain 

quarterly records of captured or transferred CO2 streams and composition.

(b) The owner or operator of a CO2 production well facility must maintain quarterly 

records of the mass flow or volumetric flow of the extracted or transferred CO2 stream and 

concentration and density if volumetric flow meters are used.

(c) Importers or exporters of CO2 must retain annual records of the mass flow, volumetric 

flow, and mass of CO2 imported or exported.

§ 98.428 Definitions.

All terms used in this subpart have the same meaning given in the Clean Air Act and 

subpart A of this part.
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