Deer Valley East Village was once home to the Mayflower Mine, where workers dug for gold, silver, copper and other metals for about a century, starting in the 1870s.
The mining work left behind water and soil contaminated with arsenic, lead and other heavy metals. The site also had toxic chemicals found in crude oil, known as total petroleum hydrocarbons.
The Utah Department of Environmental Quality issued a certificate of completion Dec. 2, showing that East Village developer Extell had cleaned up about 450 acres of contaminated land.
The process took about five years from the time state environmental experts approved a cleanup plan for the site in 2019, according to DEQ records.
Contaminated soils were removed and consolidated into one area, then capped with a special cover to prevent the toxins from spreading or leaking. That repository is beneath the main parking lot for East Village skiers.
A site management plan will require the local HOA to arrange annual inspections to make sure the cleanup standards are still being met. There will also be regular tests to watch for any heavy metals in the water.
Remediation work also included changes to mining-era infrastructure, like pipelines and mine portals, to prevent future contamination.
Kurt Krieg, executive vice president of Extell, said in June the remediation project is the second-largest environmental cleanup in Utah history.
