Using e-GGRT to Prepare Your Subpart TT Report

Subpart TT applies to industrial waste landfills that accepted waste on or after January 1, 1980 and that are located at a facility whose total landfill design capacity is greater than or equal to 300,000 metric tons. 

This page provides an overview of sub-topics that are central to Subpart TT reporting:

The end of this page contains links you can use for more information on these topics.

Subpart TT requires industrial waste landfills to report methane (CH4) generation and emissions quantities. First, provide the information requested in the Landfill Details page and e-GGRT will determine what additional information is required for reporting based on the information you provide about your landfill. Next, identify each waste stream placed into the landfill and provide the associated information requested by e-GGRT.

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Subpart TT Landfill Details for this Facility

The following industrial waste landfill information is collected for Subpart TT:

  • If the landfill was open or closed in the current reporting year.
  • The capacity of the landfill.
  • If the landfill has a gas collection system.
  • If passive vents and/or flares are present (other than as part of a gas collection system).
  • If leachate recirculation is used at the landfill during the emissions reporting year.
  • The typical frequency with which leachate recirculation was used over the past 10 years.
  • Some information about values used to calculate methane generation using Equation TT-1.
  • Active aeration system information (if applicable)
  • Information on data used to estimate annual waste quantities if Equation TT-4a or Equation TT-4b was used.

Subpart TT Emissions Information

Landfills that do not have a landfill gas collection system are required to report annual CH4 generation and CH4 emissions for each waste stream (i.e., the modeled methane generation for each waste stream, calculated using Equation TT-1 of this subpart, and the CH4 generation, adjusted for oxidation, calculated using Equation TT-6 of this subpart), reported in metric tons of CH4.

Landfills that have a landfill gas collection system are also required to report modeled and measured CH4 generation and CH4 emissions values and are referred to Subpart HH for the additonal required calculations (i.e., Equations HH-4, HH-6, HH-7, and HH-8). See Using Subpart HH Calculation Spreadsheets to find instructions on how to use these Calculation Spreadsheets.

Subpart TT Waste Stream Summary Information

For each waste stream disposed of in the landfill provide:

  • A unique name or identifier.
  • A description of the waste stream.
  • An indication of each type of waste (as listed in Table TT-1) present in the waste stream.
  • Information regarding the methods used to determine the degradable organic carbon (DOCx) value for the waste stream as well as the actual value of the DOCx used in Equation TT-1.
  • Method(s) used to determine the historical waste stream quantity for each year the waste stream was disposed in the landfill as well as the actual yearly quantities of waste used in Equation TT-1.
  • The decay rate (k) value for each year used in Equation TT-1.

Subpart TT Validation Report

You can use the Validation Report to assist with the completeness and quality of your reporting data.

You should use the Validation Report to check your work. The Validation Report performs three types of checks:

  • Data Completeness: Data that are required for reporting are missing or incomplete.
  • Data Quality: Data are outside of the expected range of values.
  • Screen Errors: Critical errors which prevent the acceptance of the reported data. Typically these will appear on the upload page.

You may view the Validation Report at any time.

Note that the Validation Report is intended to assist users in entering data, but it is not an indication that the reporter has entered all necessary information, nor is it an indication that the reporter is in compliance with part 98. Furthermore a negative finding on the validation report is not a guarantee that a data element was entered incorrectly.

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