This is an archived article that was published on sltrib.com in 2013, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

The Chevron pipeline that leaked diesel fuel near the Bear River Migratory Bird Refuge has passed a stress test and has been cleared to resume operations, but at limited capacity.

Cleanup crews continued this week to mop up traces of diesel from the March 18 spill, which dumped about 21,000 gallons of fuel at Willard Bay State Park. A 6-foot section had failed on the 8-inch pipeline that transports fuel from the five Salt Lake area refineries to Idaho and Spokane, Wash. Once the leak was detected, the pipeline was shut down for repairs.

The diesel leaked into the soil and drainage ditches and eventually found its way into the reservoir that draws picnickers and campers to the popular recreation spot.

The biggest casualties have been six sickened beavers whose lodges helped slow the diesel's flow, plus a few dead fish and birds. Water in the reservoir has been mildly contaminated, but not to a level that has water officials concerned.

Chevron resumed operating the line at about 80 percent of its normal pressure in early April after receiving permission from the federal oversight agency. In order to pump the fuel at 100 percent of normal pressure, a federal oversight agency mandated that the pipeline pass a stress test.

Fuel operations were halted this week for the test, and petroleum was cleared from the pipe. On Monday, water was pumped in, the pressure modulated and the pipe sprung a leak when the pressure hit the maximum 2,606 pounds per square inch.

On Thursday, a second test was conducted. At about 11 a.m., the U.S. Transportation Department's Pipeline and Hazardous Materials Safety Administration declared: "Spike test complete. No loss of pressure. Accepted test."

Agency spokesman Damon Hill noted the company had met the required safety terms.

"They repaired the part that failed [Monday] and they conducted another test," said Hill. "That test was successful."

But the company still is not permitted to pump fuel normally, only at 80 percent. The company would not comment on any details of future operations, such as when it might be cleared to run the pipeline at the normal pressure.

"The pipeline is being prepared to resume operations at a reduced capacity and is targeted to commence operating on Saturday, May 4, 2013," Chevron Pipe Line Co.'s Gareth Johnstone said in an emailed statement.

Walt Baker, director of the Utah Division of Water Quality, welcomed the news about the latest test."We are pleased to learn of the successful re-test of the pipeline," he said, "and that the integrity of the line appears to have been verified."

Meanwhile, as the cleanup continues, the North Marina of the Willard Bay State Park remains closed as its busy visitor season gets underway.

Twitter: @judyfutah