Crews worked feverishly Monday and Tuesday to remove hundreds of gallons of diesel fuel from a stream that flows into Utah Lake to keep it from contaminating more bird and fish habitat.

A Union Pacific locomotive was bumped off the track early Monday morning by the cars behind it, rupturing a fuel tank that leaked an estimated 1,500 gallons of diesel into Mill Race canal in south Provo, said Paul Beckett, a Utah County Health Department environmental health scientist.At least seven wild ducks died. So far, there's no evidence that the fuel killed any fish, including the endangered June sucker.

The spill - which came about two weeks after a similar railroad accident in Orem - has federal wildlife officials concerned about the transport of hazardous substances. The Orem spill didn't affect surface water but leeched into groundwater.

"I don't know what it's going to take to recognize that handling these materials is something we're going to have to do a better job of," said Reed Harris, U.S. Fish and Wildlife Service field supervisor for Utah.

Union Pacific Railroad could be liable for fowl poisoned by the fuel under federal laws that protect migratory birds.

Mike Furtney, a San Francisco-based Union Pacific spokesman, said the railroad will get with the proper government agencies to "do whatever needs to be done," noting it can't bring back dead animals.

"Anything we can do to remediate the area, we will do," he said. Union Pacific had an environmental contingent on the scene Tuesday.

The canal winds its way through East Bay Golf Course before reaching Utah Lake. Harris said it might be some time before officials know the effects of the spill. In addition to the dead birds, Harris said, many other birds are or will get sick. "They'll go off somewhere and die," he said.

Fish could also die as a result of the diesel fuel getting into the water column.

"That ends up being a problem long term unless we can get dilution," Harris said.

The Provo Storm Water Service District and Provo Fire Department used a boom Monday to trap the diesel and skim it from the water's surface. Union Pacific also hired a clean-up crew to work the waterway Tuesday, Beckett said. The goal is to keep it from running into the lake.

"We're definitely seeing the diesel," he said, adding he doesn't know if crews can prevent it from getting to the lake. "A drop of oil or gas on water can go a long way."

That troubles Harris, who said spills are occurring much too often. Two other oil spills this year, including, one near the Utah State Hospital, have leaked in drainages that lead to Provo Bay, he said.

"Once it gets to be so chronic, what we're afraid of is birds just can't make it. We don't want to see that happen," he said.

Provo Bay and south Provo wetlands are nesting areas for all types of migratory birds, water fowl and songbirds. Birds and other wildlife use the canal for feeding.

Fish and Wildlife officials will try to track the effects of Monday's diesel spill by depending on residents to report evidence of dead birds or fish.