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In 2015, a field study was conducted on two texturally different copper mine tailings in British Columbia, Canada. The objective of the study is to determine the long term response of carbon and nitrogen concentrations and identify if there is a long term benefit of a one-time biosolids application during mine tailings reclamation. In August 1998, anaerobically digested biosolids were applied in a randomized complete block experimental design to a sand and a silt loam tailings pond at rates of 0 (control), 50, 100, 150, 200 and 250 Mg ha-1. In July 1999 all experimental plots were seeded with an agronomic seed mix. Soil samples were taken from a depth of 0-15 cm, September 1998, 1999 and 2000 (1, 13, and 25 months after biosolids application) and 2015, 17 years after treatment applications. Both carbon and nitrogen concentrations increased due to biosolids applications in 1998, and then decreased in 1999. Carbon concentrations then increased from 1999 to 2000 and from 2000 to 2015. Depending on tailings texture, nitrogen concentrations display increases or decreases between 1999 and 2000, and then increases between 2000 and 2015. This data provides insight into the long term trajectory of tailings ponds reclaimed with a one-time biosolids application. The current study supports the hypothesis that biosolids provide a long term benefit on mine tailings, and support a positive, self-sustaining trajectory.