USOR (U.S. Oil & Refining Co.) began in 1952 as Pacific Oil & Refining Co., a privately held corporation. Its first president was Dr. Ernest Lyder. The company was formed to build an oil refinery in the
Pacific Northwest. In 1954, the refinery's present site in
Tacoma was purchased, and in 1955 the corporation was renamed U.S. Oil & Refining Co. Construction of the initial facility, a (stream) refinery, began during the summer of 1955.
Chico Marx entertained at the ground-breaking ceremony on July 22, 1955, for the new $10 million plant. Tacoma Mayor Harold Tollefson and senators
Warren G. Magnuson and
Henry M. Jackson also attended the ceremony. Construction was completed in mid-1957 and the refinery in full operation by the end of the year. The site had been a favorite spot for fishing, swimming, and duck hunting in earlier years. The west end of the site had once been the city landfill, which at one time contained (unmodified, unstripped)
Japanese Zeros brought over from after
World War II. The east end of the site was once
wetlands. A second crude unit, capable of processing
heavy crude oil, used in the manufacture of paving grade asphalt, became operational in 1959. USOR was sold to
Astra Oil Trading, a subsidiary of
Transcor, in 2006. Astra sold USOR to
TrailStone in 2014, which is funded by
Riverstone Holdings, a private equity firm founded by key
Goldman Sachs entrepreneurs. == Products and facility ==