Regional District of Nanaimo Fabricated Soil for Landfill Cover

Through an assessment of local biosolids management options that SYLVIS completed for the Regional District of Nanaimo (RDN), soil fabrication using biosolids was identified as a viable contingency option for management of a portion of the RDN’s biosolids.

The Nanaimo Forest Products Harmac Mill in Nanaimo, BC operates a landfill for management of ash from its power boilers. This landfill will be closed in sections over a number of years as mill operations continue. Landfill closure includes installing a growth medium for the establishment of vegetative cover which protects the closed landfill against erosion and infiltration of rainwater.

Regional District of Nanaimo (RDN) biosolids are mixed together with native mineral soil, wood waste to produce a fabricated soil / growth medium at a lower cost to Harmac than commercially available topsoil. SYLVIS provides qualified professional oversight of the soil mixing project, including regulatory authorization, calculation of an appropriate feedstock mixing ratio, and carrying out a QA/QC program to ensure that fabricated soil meets quality criteria.

Since 2017 over 7,000 cubic metres of mixed soil has been produced and is currently being stored, awaiting use as the landfill growth medium. This project continues in 2020, serving as a valuable contingency site in the RDN’s biosolids management program.