out of Paine Field without significantly adding to local noise and traffic. The findings cleared the way for commercial operations along with the construction of a terminal building. On February 5, 2013, the cities of Edmonds and Mukilteo, along with two individuals, filed notice with the 9th U.S. Circuit Court of Appeals in San Francisco that they intend to challenge the results of the Environmental Assessment. On July 15, 2013, Allegiant Air refused the county's terms to operate a terminal at Paine. Commercial service resumes In June 2014, New York-based Propeller Investments asked Snohomish County to start discussions leading to their construction of a terminal and parking facility at Paine Field. Propeller Investments would shoulder the risk — leasing land from the airport, financing terminal construction, and finding tenant airlines. On March 2, 2015, Snohomish County approved a lease-option agreement that gave Propeller Airports three years to carry out preliminary design work, environmental studies and to obtain permits needed to construct a proposed two-gate passenger terminal. In turn, Snohomish County would receive about $429,000 per year in rent plus a share of flight and parking revenues. On March 4, 2016, a federal court denied an appeal by the City of Mukilteo and other citizens groups to prevent commercial flights at Paine Field. The ground was broken for the passenger terminal on June 5, 2017. The 30,000 square foot building will have two gates and will be capable of handling about 16 flights per day. The operator, Propeller Airports, has agreed to limit early-morning and late-night commercial flights to reduce noise impacts on Mukilteo and nearby residential areas. Alaska Airlines was the first to announce in May 2017 would operate from Paine Field. The airline initially announced that it would fly nine daily flights with a mix of mainline and regional jets. In January 2018, Alaska announced that instead all flights from Everett would be operated by its regional subsidiary, Horizon Air using the Embraer 175 regional jet, but that it would be offering 13 flights each day. In November 2018, the number of daily departures was again increased to 18. Alaska plans daily flights to several west coast destinations: Las Vegas, Los Angeles, Orange County, Phoenix, Portland, San Diego, San Francisco, and San Jose. United Airlines announced on August 10, 2017, that six flights a day will be operated to its hubs in Denver and San Francisco. Southwest Airlines announced