year 1980 marked the beginning of a worldwide copper recession which
initiated significant changes for Kennecott. Standard Oil of Ohio (SOHIO)
in 1981 acquired Kennecott, including the company's Utah Copper operations
which had over 7,500 employees. In 1985 operations ceased at the Bingham
Canyon mine. New labor agreements were negotiated in 1986, and resumption
of all Kennecott Utah Copper operations occurred in 1987. British Petroleum
acquired total control of SOHIO in 1987, with Kennecott becoming part
of BP Minerals America. In 1988 Kennecott announced a $400,000,000 modernization
program under president Frank Joklik.
revitalized Kennecott Utah Copper began 1988 with the completion of
a peripheral tailing discharge system at the tailings pond near Magna,
and the start-up of modernized facilities at Bingham and Copperton.
These included an in-pit crusher, conveying system, and three grinding
lines in the Copperton concentrator, which processed about 85,000 tpd.
Rio Tinto Zinc (RTZ) Corporation purchased Kennecott in 1989 and continued
the company's expansion. In 1990 a fourth grinding line at a cost of
$220,000,000 was begun at the Copperton Concentrator, and it was completed
in 1992. This increased the concentrator's production to 125,000 tpd.