InsideClimate News reporter Lisa Song. (Reuters)

InsideClimate News, which won the Pulitzer Prize for National Reporting on Monday for its coverage of the 2010 Enbridge pipeline spill in Michigan’s Kalamazoo River, has just seven employees and no office. But as Executive Editor Susan White jokes, “We’ve got all the time zones covered.”

The Web-only publication, which was founded in 2008, has reporters and editors scattered among New York, San Diego and Tel Aviv. But the scrappy outfit — which is primarily funded by the Rockefeller Brothers Fund, the Marisla Foundation and the Grantham Foundation for the Protection of the Environment — has made its mark by pursuing investigative journalism rather than aggregating other publications’ coverage.

“We try to fill in the gaps that exist in American journalism that are more and more common,” said David Sassoon, the site’s founder and publisher.

In the case of “The Dilbit Disaster: Inside the Biggest Oil Spill You’ve Never Heard Of,” it meant a seven-month investigation that found that the rupture of a pipeline carrying diluted bitumen from Canada’s oil sands region resulted in the largest onshore oil spill in U.S. history.

Sassoon said the reporters who ended up pursuing the story — Lisa Song, Elizabeth McGowan and David Hasemyer — were prompted to pursue it because Americans were wondering what would happen if the proposed Keystone XL pipeline extension would leak oil into Nebraska’s Ogallala Aquifer.

Song had interviewed landowners living along the proposed Keystone XL route, White said, and had met people “who lived in this really barren place” and had learned how to eke out a living there over generations.

“These people were saying, ‘What will happen to us out here, if there was a spill?’ ” White recalled. “We decided to go back and pull that apart.”

Curtis Brainard, a staff writer at the Columbia Journalism Review who covers science, wrote a piece in July saying InsideClimate had managed to delve deeper into the issue than any other publication.

“Nobody was paying attention to this,” Brainard said, adding that the series managed to “highlight flaws in the U.S. pipeline system. . . . They were just right on top of it and really stuck it to the federal government on this one, and to Enbridge, for that matter.”

White said the Web site, which is aimed at people focused on energy and climate issues, tried to write the series as a narrative rather than a straight investigative project.

“We need to broaden our audience, because the people who need to read our stories are not the people who already understand them,” she said, adding that there were days when the site did not have fresh news because the staff preferred to pursue long-term stories.

Although the group is funded by environmentally-minded foundations, and was named “SolveClimate News” when it was founded, White said it is driven solely by the facts.

“We’re interested in environmental issues and we’re interested in energy issues because they’re connected,” she said. “But we don’t have an agenda. We write what we find.”

Brainard said Sassoon and his colleagues deserve credit for pursuing important environmental stories, including the recent Exxon pipeline spill in Mayflower, Ark.

“He’s really built this operation up brick by brick, and he has worked his tail off to do it,” he said. “Its work is driven by facts, and well-supported facts. They’re real shoe-leather journalists.”

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