40 CFR 98.528 - Definitions.

Regulations last checked for updates: May 01, 2025

Title 40 - Protection of Environment last revised: Nov 01, 2025

§ 98.528 - Definitions.

All terms used of this subpart have the same meaning given in the Clean Air Act and subpart A of this part.

Table 1 to Subpart ZZ of Part 98—CO2 Emission Factors for Carbonate-Based Raw Materials

Carbonate	Mineral name(s)	CO2 emission factor ^a
BaCO3	Witherite, Barium carbonate	0.223
CaCO3	Limestone, Calcium Carbonate, Calcite, Aragonite	0.440
Ca(Fe,Mg,Mn)(CO3)2	Ankerite ^b	0.408-0.476
CaMg(CO3)2	Dolomite	0.477
FeCO3	Siderite	0.380
K2CO3	Potassium carbonate	0.318
Li2CO3	Lithium carbonate	0.596
MgCO3	Magnesite	0.522
MnCO3	Rhodochrosite	0.383
Na2CO3	Sodium carbonate, Soda ash	0.415
SrCO3	Strontium carbonate, Strontianite	0.298

^a Emission factors are in units of metric tons of CO2 emitted per metric ton of carbonate-based material.

^b Ankerite emission factors are based on a formula weight range that assumes Fe, Mg, and Mn are present in amounts of at least 1.0 percent.

authority: 42 U.S.C. 7401-7671q.

source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.

cite as: 40 CFR 98.528