Enbridge Energy Partners is being investigated after some 1,200 barrels of oil spilled into a field near Grand Marsh, Wisconsin, causing the shutdown of the company鈥檚 pipeline that transports light crude from Canada to refineries in the Chicago area.

The company reported that the spill, which took place at approximately 2:45 am Friday, had been contained on the field, which is mostly on the pipeline right-of-way.

"Enbridge is treating this situation as a top priority," Richard Adams, vice president, U.S. Operations, Enbridge said in a news release issued late Friday.

"We are bringing all necessary resources to bear. Our immediate focus is on keeping our workers and the public safe as we work to remove the oil and clean up the site."

On Saturday, Enbridge spokesperson Graham White said the spill has not impacted any water sources.

鈥淭here鈥檚 no flowing water here, there鈥檚 no rivers or streams,鈥 White told CTV Edmonton. 鈥淪o fortunately we haven鈥檛 had any impact on any running water.鈥

U.S. officials confirmed Saturday that they are on scene, conducting an investigation.

鈥淚 can confirm that Enbridge Energy Partners experienced a leak on their Line 14 pipeline in Adams County, Wisconsin. The Pipeline and Hazardous Materials Safety Administration has authority over this operator and has sent inspectors to the site to conduct a failure investigation,鈥 said Damon Hill, a spokesman for the U.S. Department of Transport.

鈥淭he Environmental Protection Agency is on the on-scene coordinator.鈥

The affected line has a capacity to transport 317,600 barrels per day. Enbridge said it was not clear when the line could be restarted.

The spill comes two years after another Enbridge spill in Michigan.

The U.S. National Transportation Safety Board (NTSB) slammed the company's response to that leak, in which some three million litres of crude spilled into wetlands, a creek and the Kalamazoo River. The river was recently re-opened for recreational use.

The company appears to have acted faster Friday than it did two years ago to stop oil from spilling.
 
Enbridge reported Friday that when control room employees detected a pressure drop on Line 14 鈥渙perators shut down and immediately isolated the line. Enbridge emergency crews were promptly deployed to the site.鈥

The U.S. NTSB said that in the spill two years ago, Enbridge control room employees misinterpreted alarms signalling a problem with the pipeline and pumped more oil into it -- twice -- instead of shutting it down. The NTSB said it took more than 17 hours to respond properly.

White said Saturday that the quick response to the most recent spill is 鈥渧ery indicative of the considerable improvements we鈥檝e made not just in the past two years, but even in the last year in areas like leak detection, pipeline control centre operations.鈥

Enbridge has been in the news in Canada this month for its proposed Northern Gateway pipeline. The company wants to build a pipeline between Alberta and the West Coast so that Canadian crude can be shipped overseas to Asia by tanker and garner a higher price.

The Northern Gateway proposal met stiff resistance from B.C. First Nations groups and others. The pipeline is also at the centre of an argument between B.C. Premier Christy Clark and Alberta Premier Alison Redford over how to fairly divvy up the project's risks and rewards.

Enbridge president Al Monaco told a recent TD Securities Energy Conference that his company has learned lessons from the Kalamazoo River spill that would be applied to the Northern Gateway pipeline.

Earlier in July, the company announced safety improvements, including thicker pipe and better monitoring, that pushed the Northern Gateway project's pricetag by $500 million to $6 billion.

Enbridge plan to move oil from west to east approved

On the same day as the latest oil spill, the National Energy Board said it had approved Enbridge Inc.'s plan to reverse the flow of part of an oil pipeline in southern Ontario.

The federal watchdog said Friday it has imposed 15 conditions on the $16.9-million project, mainly having to do with pipeline integrity.

Line 9 currently flows from Montreal to Sarnia, Ont., but Enbridge wants it reconfigured so it flows from west to east.

Refiners in central and eastern Canada want to use cheaper Canadian crude instead of pricier oil imported by tanker from overseas.

The NEB approval pertains to the section of pipe between Sarnia, Ont., and West over, Ont., near Hamilton.

In May, the board held hearings where it heard concerns from the public about possible spills from the pipeline.

Environmental Justice Toronto said Saturday it was organising a protest of the NEB decision to be held on Monday outside the office of Peter Kent, Minister of Ethical Oil.

Labour Minister Lisa Raitt, a former natural resources minister, said the NEB decision is "quite important" as it helps improve pipeline access to Canada's coasts and customers in the U.S.

Raitt said the reversal reflects what customers want and need and keeps Canada's oil flowing in a way that is most economic, adding that customers on the east coast will be able to receive cheaper crude from North America rather than have to import it from abroad.

"Energy is a matter of national importance and the government welcomes efforts to better utilize our energy assets for the benefit of Canadians from coast to coast to coast," she said.

"So in this respect the expansion and the diversification of our energy markets is one of our priorities."

Enbridge rival TransCanada Corp. is also working on a plan to ship western Canadian crude east. It's looking at converting its gas mainline, which is running partly-empty, to gas service. It could ship between 400,000 and 900,000 barrels per day of oil, depending on customer demand.

With files from The Canadian Press and a report from CTV Edmonton鈥檚 Amanda Anderson