FAQs- UNIT EMISSIONSInformation on the Data Sources Used to Obtain the Greenhouse Gas (GHG) Unit Emission FactorsThe data for each combination study region- waste management process obtained from facilities during the data collection survey and supplemented with literature data (See April 14, 2009 Interim Project Report) were used as input to RTIs MSW DST. RTIs MSW DST provided study region- waste management process- waste category specific GHG emission factors for the following processes: Collection Transportation for all modes, except ocean freighter. Franklin Associates, LTD. (1998) was used for ocean freighter. Compost preparation, excluding application Chipping and grinding, excluding application (emissions from tub grinders and rolling stock operation as obtain from the MSW DST were used) Recycling, separation and remanufacturing (excluding forest carbon sequestration) BTE (data were obtained only for combustion of biomass and energy recovery) WTE Landfill disposal (excluding carbon storage)RTIs MSW DST does not provide emission factors for N2O, only for CO2 and CH4, and RTI used the following data sources to obtain N2O emissions: Used IPCC (2006) and data collected during compost sampling for Brown et al. (2009) for compost preparation (excluding application) Used US.EPA (2006) and Franklin Associates, LTD. (1998) for WTE and BTE Used IPCC (2006) for AD, landfill disposal (leachate treatment and energy generation at landfills with energy recovery)N2O emissions from other processes (e.g., transportation) are less significant than CO2 emissions. When data were available from the sources consulted RTI considered those data and additional data sources were not consulted.RTI used additional data sources for other processes not included in the MSW DST as follows: Used data collected during compost sampling for Brown and Cotton (2009) for compost and mulch application emission burdens Used ROU (2006) for compost and mulch application energy burdens and for compost application energy offsets Used Brown and Cotton (2009) for compost application emission offsets Used US.EPA (2006), for recycling emissions offsets associated with forest carbon sequestration Used RTIs AD model (RTI, 2005) in combination with the data presented in the April 14, 2009 Interim Project Report for AD emissions and energy burdens and offsets Used Franklin Associates, LTD. (1998) for emissions burdens associated with using natural gas as supplemental fuel in BTE facilities Used CARB (2009) for energy and emission burdens associated with CNG production and Franklin Associates, LTD. (1998) for offsets associated with replacing natural gas with CNG as vehicle fuel. Used Staley and Barlaz (2009) for landfill emission offsets associated with carbon storageInformation on the Calculations Used to Obtain the By-Process Greenhouse Gas (GHG) Unit Emission Factors RTI calculated net emission factors for each waste management process according to the LCA boundaries defined in the April 14, 2009 Interim Project Report. Burdens and offsets were identified and factored in as presented in the following table.Waste Management ProcessProcess ComponentBurdens (A)Offsets (B)% Mass Flow to Different Activities (C) (1)Net Value CalculationCompost CollectionNAUser DefinedC = (A)Compost preparation- Windrow or ASPNAUser DefinedP = (A)Compost applicationVaries according to the waste category or User DefinedA = (A) - (B)Product (compost) transportationNAVaries according to the waste category or User DefinedPT = (A)Residuals transportationNAUser DefinedRT = (A)Residuals disposal at LF (1)User DefinedLF = (A) - (B)COMPOST NET GHG EMISSION OR ENERGY FACTOR (CNEMF)CNEMF = C + P + (C)*A + (C)*PT + (C)*RT + (C)*LFChipping and GrindingCollectionNAUser DefinedC = (A)Mulch preparationNAUser DefinedP = (A)Mulch applicationUser DefinedA = (A) - (B)Product (mulch) transportationNAUser DefinedPT = (A)Residuals transportationNAUser DefinedRT = (A)Residuals disposal at LF (1)User DefinedLF = (A) - (B)CHIPPING AND GRINDING NET GHG EMISSION OR ENERGY FACTOR (C&GNEMF)C&GNEMF = C + P + (C)*A + (C)*PT + (C)*RT + (C)*LFRecyclingCollectionNAUser DefinedC = (A)Separation at MRFNAUser DefinedS = (A)RemanufacturingUser DefinedR = (A) - (B)Product (recyclables) transportationNAUser DefinedPT = (A)Residuals transportationNAUser DefinedRT = (A)Residuals disposal at LF (1)User DefinedLF = (A) - (B)RECYCLING NET GHG EMISSION OR ENERGY FACTOR (RNEMF)RNEMF = C + S + (C)*R + (C)*PT + (C)*RT + (C)*LFAnaerobic DigestionCollectionNAUser DefinedC = (A)ADUser DefinedAD = (A) - (B)Leachate treatment