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Al Hartmann | Tribune file photo The Salt Lake Valley during a 2016 day when levels of health-threatening ozone levels were high. Steve Griffin / The Salt Lake Tribune The Salt Lake City skyline is visible through the hazy air in Salt Lake City Tuesday Januar Chris Detrick | The Salt Lake Tribune A pollution inversion over the Salt Lake Valley as seen from an airplane leaving from Salt Francisco Kjolseth | Tribune file photo In this February 2016 file photo, Jason Dunn of Draper seeks higher, cleaner air as he ri