Umetco Minerals Corp. is laying off 83 more workers as a result of the indefinite closure of its uranium and vanadium mining and milling operations in southeastern Utah and southwestern Colorado.

The cutbacks are the result of depressed domestic prices for uranium and vanadium and increased foreign competition, which has grown to about 25 percent of the U.S. market, said Umetco President P.K. Willmott.The company has furloughed 58 workers at its Dove Creek, La Sal and Sunday mines and laid off 25 employees at its White Mesa mill. Last month, Umetco reduced its workforce by 97 employees.

A small number of workers will maintain the mines and mill "on a standby basis," said Willmott.