General Stationary Fuel Combustion (Subpart C) and the Inputs Verification Tool

Should You Use the Inputs Verification Tool for Subpart C?

Beginning in RY2014, facilities will need to determine if they should use the Inputs Verification Tool (IVT) to calculate emissions or if they should report the inputs to EPA for each configuration reporting under Subpart C. The following flowchart outlines this decision process:

Note: There is no difference in the calculations conducted when using IVT or when reporting inputs to EPA. This decision only impacts how your data will be handled. If you chose to use IVT, the inputs data will not be sent to EPA – it will be your responsibility to save your inputs verifier file (see Entering Inputs and Saving Them Locally). If you chose to report inputs to EPA, you will not need to create or save the inputs verifier file.

Once you have determined whether or not you will use IVT for a configuration, you can then determine if you are subject to back year reporting requirements. Facilities will need to submit deferred data for RY2010-2013 for any configuration where they do not use IVT. See Deferred Reporting: Subpart C for information on submitting deferred data for Subpart C. Facilities that use IVT for all configurations will not need to submit deferred data.

How do I enter this decision into e-GGRT?

Before you can begin data entry for any configuration under Subpart C, you will need to indicate whether or not you plan to use IVT for that configuration. E-GGRT will prompt you with several questions to guide you through this decision. Following is a description of how to navigate these screens.

When adding a new configuration, you will see a button labeled "Help me determine..." beneath "Will this configuration use IVT?" in the EQUATION INPUTS REPORTING FOR RY2015 section of the Edit Configuration Information page. Click this button to display the first question.

Click this link to expand

Question 1. E-GGRT will ask you if the facility and the stationary combustion source configuration (e.g., individual unit, aggregation of units, common pipe, or common stack) meet both of the following conditions:

  1. The facility contains at least one combustion unit that is connected to a fuel-fired electric generator owned or operated by an entity that is subject to regulation of customer billing rates by the public utility commission (PUC) (excluding generators connected to combustion units subject to 40 CFR part 98, subpart D); and
  2. The source configuration is located at a facility for which the sum of the nameplate capacities for all such electric generators is greater than or equal to 1 megawatt electric output.

If both conditions are met, the facility is required to report inputs and cannot use IVT for the source:

If you answer “yes” and click SAVE, e-GGRT will return you to the Edit Configuration Information page, where "This configuration will not use IVT for equations calculations and will report equation inputs to EPA" will be displayed in the EQUATION INPUTS REPORTING FOR RY2015 section of the page.

If you answer “no,” you will be directed Question 2.

Click this link to expand

Question 2. E-GGRT will ask if you would like to use IVT or if you would like to report inputs to equations to EPA for the configuration.

If you select that you would like to use IVT and click SAVE, e-GGRT will return you to the Edit Configuration Information page, where "This configuration will use IVT for equations calculations and as a result, will not report equation inputs to EPA" will be displayed in the EQUATION INPUTS REPORTING FOR RY2015 section of the page.

If you select that you would like to report inputs to EPA, you will be directed to Question 3.

Click this link to expand

Question 3. E-GGRT will ask you to confirm that you would like to report inputs and that you waive confidentiality claims to the inputs to equations entered for the configuration or whether you would like to return to Question 2 to reconsider this decision.

If you select the "Proceed with reporting my inputs to equations to the EPA" radio button and click SAVE, e-GGRT will return you to the Edit Configuration Summary page, where "This configuration will not use IVT for equations calculations and has chosen to report equation inputs to EPA." will be displayed in the CONFIGURATION INFORMATION section of the page.

If you select the "Return to the previous question" radio button, e-GGRT will return you to Question 2. 

Click this link to expand

When e-GGRT returns you to the Configuration Summary page, your selection with respect to using IVT will be displayed in the CONFIGURATION INFORMATION section of the page. If you intend to make the same choice for all the configurations you report under subpart C, click the "Apply selection to all my configurations" button.  

Click this link to expand

This web site is maintained by a contractor to the U.S. Environmental Protection Agency (RY2023.R.01)