Resolve Earthworks & Environmental Ltd. was awarded the contract to remediate a former substation site and select lands off property. The project presented numerous challenges including but not limited to: overhead powerlines located within excavation footprint; deep excavation (5 to 9m below surface); high groundwater table; excavation immediately adjacent to Town roads and sidewalks, as well as a neighboring business and building that remained operational.

Resolve was awarded the project based on its overall price and proposed work plan, as well as its safety record and proven capabilities on similar projects. 

The project scope included the following:

• Work in conjunction with shoring subcontractor to develop a shoring system and excavation plan that would be most suitable to achieve the target excavation limits without compromising the surrounding infrastructure including roadways, sidewalks, overhead & underground utilities, and adjacent building (operating commercial business).

• Coordination with site owner, environmental consultant, Town Administration, utility owners, and adjacent businesses to develop a work plan agreeable to all parties, and acquire all required permits and approvals.

• Complete utility location and property boundary survey.

• Disconnection and removal of former water service line into the site to facilitate shoring wall installation, and installation of new curb stop outside property line to allow for future reinstatement service line.

• Permanent removal and rerouting of overhead powerlines in area of excavation.

• Coordinate the design and installation of secant pile shoring wall on 3 sides of excavation to allow vertical excavation between 5 – 9m below ground surface.

• Removal and offsite recycling of concrete from sidewalk and buried foundation of former site building.

• Excavation and stockpiling of overburden soils.

• Excavation, transport and disposal of over 5,000 mt of petroleum hydrocarbon (PHC) impacted soils to a Class II landfill.

• Dewatering, off-site temporary storage, and subsequent hauling and disposal of PHC impacted groundwater.

• Installation of hydrocarbon-resistant liner at excavation boundary to prevent re-contamination of remediated areas.

• Backfill and compaction of excavated area using stockpiled overburden materials and imported clean fill.

• Assist with planning of future remedial activities at site.