Find out about how we're managing the Marwell Tar Pit site

Government of Yukon staff overseeing the Marwell Tar Pit site.

Where is it?

  • In the Marwell Industrial Area of Whitehorse.
  • Less than 500 metres from Two Mile Hill, at the foot of the Takhini East bluffs.
  • The Marwell tar pit site is fenced off and has posted signs.

History of the Marwell Tar Pit remediation project

  • Part of a crude oil refinery that operated for less than 1 year before closing in March 1945.
  • When the refinery was dismantled, sludge from the refinery tank bottoms ended up in the pit of a dismantled storage tank.
  • The deposits were covered with locally-sourced soils.
  • Declared a "Designated Contaminated Site" in 1998 under the Environment Act.
  • In June 2010, the governments of Canada and Yukon agreed to jointly fund the remediation of the Marwell Tar Pit.

Current work

  • Excavation began in May 2018 and is expected to continue into December 2019.
  • The contaminated soil is segregated and treated on site using Enhanced Thermal Conduction.
    • This process heats the soil and vaporizes the contamination.
    • Vapours are then captured and destroyed through “burning” that meets air quality standards.
    • CO2 and water vapour remains.
    • The remediated soil is then used to backfill the excavation.
  • On-site treatment of soil is not expected to cause public health concerns.
  • This method of remediation has been used elsewhere for decades, but this is only the second time it has been used in Yukon.

Project timeline


  • Project started in 2011 with assessment work.
  • This determined the extent and types of contamination.


  • Contract for remediation work awarded in February.
  • Construction work began in May.
  • Excavation and remediation began in July.


  • Excavation and remediation paused for January through mid-March.
  • Excavation and remediation is expected to continue until December.
  • Monitoring will continue in the years following the project's completion.



For questions about government-owned contaminated sites, email or phone 867-667-5683, or toll free in Yukon 1-800-661-0408.