11.1 Sector Descriptions and Overview

Greenwaste composting includes the diversion of yard waste, food waste, and other biogenic waste from landfills to composting facilities. Estimates of emissions of volatile organic compounds (VOC), ammonia (NH3), and three hazardous air pollutants (HAPs), acetaldehyde; methanol; and naphthalene, from greenwaste composting are based on the amount of food and yard waste composted. Composting of biogenic waste is currently not included in emissions estimates for this category as activity data on this waste type is not available.

Note that this source category does not include the composting of biosolids from wastewater treatment plants or manure management facilities. There are separate SCCs for biosolids (2680001000) and for a mixture of greenwaste and biosolids (2680002000). EPA is not currently estimating emissions for these SCCs. If S/L/Ts report any emissions for the mixture SCC, emissions from the greenwaste portion of that mixture may be duplicative of some or all of the EPA emissions estimates described here. Note also that this source category estimates emissions from composting facilities but does not estimate emissions from backyard composting.

Table 11.1 shows, for composting, the SCCs covered by the EPA estimates and by the State/Local and Tribal agencies that submitted data. The SCC level 3 and 4 SCC descriptions are also provided. The SCC level 1 and leading level 2 descriptions is “Waste Disposal, Treatment, and Recovery; Composting:” for all SCCs.

Table 11.1: Source Classification Codes used in the compost sector.
SCC Description EPA S/L/T
2680001000 100% Biosolids (e.g., sewage sludge, manure, mixtures of these matls); All Processes X
2680002000 Mixed Waste (e.g., a 50:50 mixture of biosolids and green wastes); All Processes X
2680003000 100% Green Waste (e.g., residential or municipal yard wastes); All Processes X X