Woodcache PBC

Decomposition of Forest Products Buried in Landfills

Xiaoming Wang, Jennifer M. Padgett, John S. Powell, Morton A. Barlaz
Waste Management
Peer Reviewed: Yes
Year Published: 2013

Key Takeaways

  • More lignified materials exhibit less anaerobic degradation in landfills.
  • No significant degradation was observed in wood samples, with the exception of oriented strand board (OSB) and Red Oak.
  • The carbon conversion of wood under landfill conditions is well below the recommended assumption in the 2006 IPCC Guidance.
Decomposition of wood products buried in landfills
This entry is part 5 of 5 in the series Do Wood Vaults Really Work?


The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g1 dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported.