Published: Sep 23, 2011 7:48 PM EDT
Updated: Sep 23, 2011 11:09 PM EDT

BILLINGS, Mont. (AP) - Montana's chief environmental regulator says a failed Exxon Mobil pipeline that spilled an estimated 42,000 gallons of oil into the Yellowstone River is likely to be restarted Friday.
    
Department of Environmental Quality Director Richard Opper says changes made during repairs to the Silvertip pipeline have made it less likely to fail again. The line broke July 1 after flooding scoured the river bottom and exposed the pipe, which was buried just five feet deep in some areas.
    
A replacement segment was installed an estimated 60 to 70 feet beneath the riverbed.
    
Cleanup of the spilled oil continues. Exxon Mobil and the DEQ are negotiating terms of the remaining work.
    
Silvertip is the main crude source for Exxon Mobil's 60,000-barrel a day refinery in Billings. A company spokeswoman declined comment.

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