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Draft Supplemental Environmental Impact Report Page IV.D-28 Forward Inc. Landfill 2018 Revised Project reductions from energy displacement are a credit for the landfill as the production of electrical energy is displacing GHG emissions from electrical generation from other sources. The off-site haul truck mobile emissions are on-road emissions from transporting the wastes to Forward Landfill. The carbon sequestration is also a credit for the landfill. However, as a conservative assessment the sequestration is not included in the calculation.211 Thus,the total GHG emissions from Forward Landfill are the sum of the methane emissions plus the stationary combustion emissions plus off-site haul truck emissions minus the energy displacement credit. Table IV.D-6: GHG Emissions (metric tons equivalent CO2 per year) Methane Energy Off-Site Haul Total kCurrentSActual enario Credits Truck Emissions JL AL Emissions Emissions 23,147 -5,088 9,236 27,295 Current Permitted 45,385 -6,846 27,011 65,550 Project(Flare) 51,561 -6,846 27,011 71,726 Project(LFG Engines) 65,315 -23,999 27,011 68,327 Project(Flare)—Current Actual 44,431 Project(LFG Engines)—Current Actual 41,033 Project(Flare)—Current Permitted 6,176 Project(LFG Engines)—Current Permitted 2,777 SOURCE: SCS Engineers,2018;modified by RCH Group NOTES:GHG emissions were calculated for four scenarios: •Current Actual,which assumes no waste placement occurs at Forward after 2017; •Current Permitted,which assumes waste placement continues until the site reaches its current permit limit; •Future Permitted(Flare),which is the Project scenario assuming all LFG not sent to the LFGTE or Ameresco facilities is destroyed in a flare; •Future Permitted(LFG Engines),which is the Project scenario assuming all LFG resulting from the Project is destroyed in an engine and the energy is recovered as electricity. See AQIA Table 3-10 for more information on landfill GHG emissions.See AQIA Table 3-14 for off-site haul vehicle emissions. On-site operational equipment emissions are not included because the use of such equipment will not increase with the project,see AQIA Table 3-16. Energy Credits(negative number in the table)reflect the amount of GHG emissions that are displaced by the electrical power generated by the LFGTE facilities at the Forward Landfill under the various scenarios. Because of the electricity generated by the LFGTE facilities,there is less demand for electricity from other power plants and thus the criteria air pollutant and GHG emissions from the other power plants are reduced(resulting in the GHG Energy Credits). Bold Underlined Values are above significance threshold Example:Project(Flare)—Current Actual=71,726—27,295=44,431 metric tons Values are averaged over a 60-year period and are representative of overall impacts.Peak emissions would be higher than emissions shown. 21 Landfills are a place where carbon is stored,removing it from the carbon cycle and preventing its emission as carbon dioxide.When waste is placed in a landfill,not all of the carbon decomposes into methane and carbon dioxide.The carbon that does not decompose is sequestered in the landfill.Sequestered carbon is not emitted to the atmosphere as either carbon dioxide or methane,removing it from the carbon cycle resulting in reduced greenhouse gases.The inclusion of carbon storage in a landfill greenhouse gas calculation is not universally accepted,but it is consistent with USEPA methodologies and inventories.It should be noted that the amount of carbon sequestered is greater than the GHG emissions from the landfill for all scenarios. If carbon storage is included in the GHG total for the project the Project lowers the GHG emissions because more carbon is sequestered in the landfill where it would not be emitted as either methane or CO2.