A pipeline that leaked 20,000 gallons of diesel fuel near northern Utah’s Willard Bay has failed a federally mandated pressure test required to make it fully operational again.

The pipeline owned by Chevron extends from Salt Lake City to Burley, Idaho.

John Whitehead of the Utah Division of Water Quality told The (Ogden) Standard-Examiner (http://tinyurl.com/csnh9gm) the 8-inch pipeline required to hold 2,600 pounds per square inch of water for 30 minutes failed after six minutes during Monday’s test.

Chevron spokesman Gareth Johnstone says the cause of the failure is under investigation. Workers plan another test this week. The pipeline has been operating at 80 percent of normal since April. Six beavers were injured but the state says trace amounts of hydrocarbons in groundwater flowing into the bay pose no danger.