MONTPELIER, Vt. — Vermont Gov. Peter Shumlin has asked Secretary of State John Kerry to require a detailed federal environmental review if the owner of an oil pipeline than runs through Vermont seeks to reverse its flow and move so-called tar sands crude from Montreal to Portland, Maine.

In a letter, Shumlin asked for a presidential permit for the pipeline and an impact statement to assess the environmental costs of reversing the pipeline.

Vermont Deputy Natural Resources Secretary Justin Johnson said the Shumlin Administration is concerned that extracting and burning tar sands oil from western Canada would add to climate change. The letter also said the state’s economy and environment would be hurt if the pipeline ruptured and oil spilled.

“So we just want to make sure that if this process goes forward all the environmental factors have been considered and that we have a good understanding both on the federal level and the state level what the risks and the rewards would be,” Johnson told Vermont Public Radio.

The pipeline line now carries conventional crude oil northwest from a terminal in Portland, Maine to refineries in Montreal.

The head of the Portland Pipe Line Corp. has said there are no current plans to reverse the flow of the pipeline, but he’s also said he’s looking for new business and the pipeline could safely carry tar sands oil.

Vermont’s District 7 Environmental Commission has also determined that the project needs a new Act 250 land-use permit if the flow is reversed to carry tar sands, but the pipeline company has asked the commission to reverse that decision.

Pipeline officials did not return a call seeking comment.