Two protesters from the Michigan Coalition Against Tar Sands, who locked themselves onto heavy equipment at a pipeline construction site, last July. Rod Sanford/Lansing State Journal/AP

President Barack Obama traveled to Michigan's Ingham County on Friday to sign the recently passed farm bill at Michigan State University, less than an hour's drive from the site of a major inland tar sands oil spill. A group of local environmentalists hopes to use the president’s visit to warn him of the potential dangers of tar sands oil ahead of his final decision on Keystone XL and other proposed pipeline projects. Three members of the group — the Michigan Coalition Against Tar Sands (MICATS) — were arrested last July 22 and face up to two years in prison for locking themselves to excavators at a construction site of the Calgary-based company Enbridge near Stockbridge, Mich. The group said the action was aimed at stopping work on Enbridge's Line 6B — the same pipeline that ruptured in 2010 near the Kalamazoo River. That spill dumped more than 800,000 gallons of tar sands oil into a tributary of the river. The pipeline had been built in 1969 to transport conventional oil. On Jan. 31, the three MICATS protesters, Vicci Hamlin, Barb Carter and Lisa Leggio, were found guilty in an Ingham County court for misdemeanor trespassing and also resisting and obstructing police. The latter, a felony charge, carries a maximum sentence of two years. During Obama’s visit, MICATS hopes to show him tar balls — toxic left-overs from the spill — that the group recently fished out of the Kalamazoo River. But the activists acknowledged that this might not be easy. "I have no delusion that I will magically bump into you," MICATS member Chris Wahmhoff wrote in a letter sent to Obama and released to the media ahead of the visit. "These are not brought for intimidation," Wahmhoff wrote. "You asked in your speech for us to make you do your job. I am telling you and your secret service, and the Ingham County police … that I am coming to honor your request."

Proof from the river

Enbridge’s proposed pipeline expansion, called the Alberta Clipper (Line 67), would almost double the amount of tar sands oil it could transport across the Great Lakes region. Enbridge did not respond to Al Jazeera’s request for comment. Another controversial pipeline project, the high-profile Keystone XL, recently gained key State Department approval. The department has yet to release its report on the Enbridge proposal. Both projects ultimately need a presidential permit to move forward. Wahmhoff said toxic chemicals and tar balls remain in the Kalamazoo River despite Enbridge’s massive cleanup efforts in the years following the spill. Wahmhoff, who once skateboarded into an Enbridge pipeline to bring attention to the controversial project, grew up on the Kalamazoo River, which, he said, after the 2010 spill was “just dead.” Obama had earlier said he would approve Keystone XL only if it could be shown not to contribute significantly to climate change. But MICATS says there is another factor that should be considered: safety. Hamlin, Carter and Leggio said they oppose Enbridge's activities out of concern for their safety, and that of their friends and family, in view of the more immediate physical threats posed by environmental pollution. The three women were denied bail and must await their March 5 sentencing in prison. The Ingham County prosecutor’s office denied it was targeting the activists for their anti-energy-industry politics. “Our office takes no position on the political beliefs of this movement. The charges would have been issued whether defendants were obstructing a military recruitment office, an abortion clinic, or a pipeline,” the office told Al Jazeera in an email, declining an interview.

‘Feels like a battlefield’