Syncrude Canada Inc. and Suncor Energy Ltd. are two oil sand operators in the Athabasca region. Following surface mining, land reclamation entails re-establishment of functioning ecosystems using salvaged mineral soil materials and organic amendments. While traditional reclamation uses peat, benefits from using the forest floor stripped from pre-mining areas were examined. This study investigated the reclamation techniques in terms of nitrogen (N) fluxes. Specifically, net N nitrogen mineralization rates and microbial biomass were measured in an undisturbed forest and several reclaimed sites at Syncrude and Suncor. Results suggested no significant difference in net N mineralization rates between sites. However, there were differences in microbial biomass possibly related to differences in moisture content. A lab experiment manipulating soil moisture content showed a positive relationship between microbial biomass N and moisture content. No relationship with microbial biomass C was found, possibly due to a shift in microbial community structure.