Northlands Denesuline FN Soil Remediation and Landfarm Upgrade - Site 1 (Former Petit Casimir Memorial School Tank Farm - FCSI # 5697) and Site 2 (Northlands Former Federal School - FCSI 5310001)

Project location: Northlands Denesuline First Nation

Description: Project is made up of #2 sites: Site 1 (Former Petit Casimir Memorial School Tank Farm - FCSI # 5697) and Site 2 (Northlands Former Federal School - FCSI 5310001)

Site 1 (Former Petit Casimir Memorial School Tank Farm - FCSI # 5697): Excavation in site #1 (also known as TTZ A) will be divided into two zones (A and B) due to the presence of underground utilities in Zone A, and its proximity to the road. Zone A will be excavated, using heavy equipment, in a series of trenches running north/south to maintain road integrity and avoid buried utilities. Each trench will have contaminated soil removed to the extent possible and field screening and sampling will be conducted during excavation to test for residual impacts. If soil impacts remain, a chemical amendment will be mixed with remaining soil prior to backfilling with clean material. Zone B will be excavated entirely and
backfilled with clean material after confirming the absence of contamination.
TTZ B will be excavated entirely and backfilled with clean material after confirming the absence of contamination. Contaminated soil will be transported to the Soil Treatment Facility (STF) using tandem trucks and placed in an even layer, maintaining a 10 m setback from the south berm to preserve sump capacity. Soil placed at the STF will be tilled during the summer months to enhance
bioremediation. Nutrient amendments may also be applied to accelerate treatment, with requirements determined based on annual soil sampling at the STF.

Site #2 (Northlands Former Federal School - FCSI 5310001), also known as TTZ G: Excavation at TTZ G will be excavated using heavy equipment, and backfilled with clean material after confirming the absence
of contamination. Contaminated soil will be transported to the STF using tandem trucks and placed in an even layer, maintaining a 10 m setback from the south berm to preserve sump capacity. Soil placed at the STF will be tilled during the summer months to enhance bioremediation. Nutrient amendments may also be applied to accelerate treatment, with requirements determined based on annual soil sampling at the STF.