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A87. If the unit is less than or equal to 250 mmBtu/hr, GHG emissions reporting is not required if the fuel or the fuel constituents are not listed in Table C-1.  However, if the unit is greater than 250 mmBtu/hr, CO2 emissions reporting for a fuel not listed in Table C-1 is required, using Tier 3, if: (1) combustion of the fuel accounts for 10% or more of the combustion unit’s annual heat input; and (2) the unit is not required to use Tier 4.  This response applies only to units that calculate CO2 emissions in accordance with Subpart C. (See §98.33(b)(3)(iii).)

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