Summit Earthworks was selected by the Ministry of Transportation and Infrastructure to complete a soil remediation, removal, and regrading project located at 7590 80th Street, Delta, B.C.
The project site contained overburden soils stockpiled from the construction of the South Fraser Perimeter Road (SFPR). The site adjacent to the SFPR RoW was also historically a former dump site. The scope of the project involved excavation of the overburden stockpile for ex-situ characterization, with clean soil directed to a non-agricultural receiving site and contaminated soil to a provincially permitted soil facility. The scope also included subsurface excavation of buried contaminated soils from the previous dump site to below groundwater elevations, along with backfilling, regrading and hydroseeding.
General scope, outline and project activities include:
- 35,000 m3 of excavated soil was windrowed for ex-situ soil characterization prior to removal from site
- Approximately, 60,000 mt of clean soil was transported from site to a non-agricultural (clean fill) receiving site
- 13 “hot spot” excavations were conducted including several below the ground water table elevation. A total of 18,000 mt of contaminated soil was excavated from these hot spots
- The project required a thoroughly prepared Construction Environmental Management Plan & Erosion Sediment Control Plan to ensure no offsite sedimentation or transfer of contaminated materials. Excavation water was managed on site via sump pumps to a water treatment system specifically designed to treat the target contaminants and reduce sediment to allow for direct discharge back to the environment
- Other ESC measures included the construction of swales and ditches to direct surface water and prevent offsite runoff, installation of silt fence and straw bales around the perimeter of the 14,000 m2 site and installation of a mechanical truck wheel wash to prevent soil tracking outside the work zone
- Following backfill and re-grading with proper slope for drainage, the site was compacted to 95% modified specification and hydroseeded
Corporation of Delta