A 5.7-magnitude earthquake struck the Salt Lake City area in Utah on Wednesday morning, causing more than 70,000 utility customers to lose power.
Rocky Mountain Power, which has more than 1.1 million customers in Utah, Wyoming, and Idaho, reported that around 73,000 customers were initially affected by the earthquake along the Wasatch Front. Later on Wednesday, that number was down to 49,000.
The Utah Division of Emergency Management tweeted that all refineries were still functioning. This was the largest earthquake to hit the state since 1992, the division noted.
Besides power outages, the earthquake yesterday caused a chemical leak at Rio Tinto Kennecott, one of the world’s largest copper mines. The Utah National Guard deployed to the site at the governor’s request, and the Immediate Response Unit announced plans to assist with air monitoring.
“We are currently conducting a full assessment of our site, and operations have been temporarily halted until we can ensure it is safe to go back to work,” Rio Tinto Kennecott posted on Twitter Wednesday.
During a press conference, Unified Fire Authority Chief Dan Peterson said, “We had been monitoring the plume from Rio Tinto Kennecott. It was hydrochloric acid and most of it was contained in a catch basin. The tank is no longer leaking.” He added that hazmat crews will continue monitoring the site.
Last year Rio Tinto permanently closed the coal plant powering its Kennecott Copper operation, a move that was expected to reduce the site’s annual carbon footprint by as much as 65%.