PORTLAND, Maine — A group of environmental advocates believe they have evidence that oil giant ExxonMobil — and perhaps even Gov. Paul LePage — are backing a plan to push controversial tar sands oil through an aging pipeline across Maine.

But Adrienne Bennett, spokeswoman for LePage, said the governor has nothing to hide on the issue, and that the administration is not advocating for such a project. She said a meeting last October between LePage and oil industry officials, pointed to by environmentalists Wednesday as a sign of his interest in moving tar sands oil through the state, was a simple “meet and greet” with no deeper ramifications.

“There are no secret behind-the-door meetings,” Bennett said. “This took place in October of last year, a year ago, and there have been no meetings since then for us to be promoting [the transportation of tar sands oil in Maine].”

Representatives of the Natural Resources Defense Council, Environment Maine, the Sierra Club and Natural Resources Council of Maine, among others, told reporters Wednesday morning during a news conference in Portland that research into the corporate parentage of the Portland Pipe Line Corp. shows a direct line to ExxonMobil, a company the environmentalists described as a major player in the field of Canadian tar sands oil extraction.

Further, the environmental advocates handed out copies of emails they said were acquired through a Freedom of Information Act request, in which Drew Cobbs of the American Petroleum Institute and Patricia Aho, commissioner of the Department of Environmental Protection, discussed an Oct. 17, 2011, meeting about Canadian tar sands oil with the governor. Among those scheduled to attend that meeting, according to the emails, were two representatives of the Portland Pipe Line Corp. and the Canadian Consulate General in Boston.

“The evidence is undeniable that this project is moving forward, albeit in pieces and behind closed doors,” said Dylan Voorhees, clean energy director for the Natural Resources Council of Maine.

Bennett, when reached by the BDN Wednesday afternoon, said the administration made no effort to cover up the meeting, which she described as introductory in nature.

“The extent of it was a meet and greet and to be introduced to these folks who were representatives of both institutions,” she said. “We’re not advocating for one thing or another. If [Portland Pipe Line officials] did decide they wanted to move forward, they would be subject to a transparent review within the state government.

“For the NRCM to insinuate that this plan is moving forward, I would simply point out that there is a fair and objective process that must take place before that can happen — and that has not occurred,” she said.

Samantha DePoy-Warren, spokeswoman for the Maine Department of Environmental Protection, confirmed that no applications tied to a pipeline project have been submitted. She said that in 2009, the department issued a draft approval of an air emissions license to the Portland Pipe Line Corp. for the reversal of the Portland-Montreal line, but that the company withdrew its application before the approval was finalized.

Since then, DePoy-Warren said, the department has not received any indication the plan is still being considered. She also said Aho was not able to attend the Oct. 17, 2011, meeting in question.

“They’ve never again walked through our door with an application or even [requested] a pre-application meeting, so anything NRCM has said today or in the past is speculative,” she said. “[NRCM officials] file FOIA requests with us all the time. If all they can find is a meeting from October 2011, it doesn’t seem like there’s much there.”

But Voorhees said Wednesday he believes the urge for big oil companies to capitalize on tar sands oil makes Maine a prime target to serve as an export path. He and the other environmental advocates on hand at the morning news conference said they’re convinced the plan remains in play.

“The dirtiest oil on the planet is coming out of the ground in Alberta, Canada, and big oil companies are desperate to transport it to ports like the one here in Portland to increase their already record-high profits,” he added. “Enter an old pipeline carrying oil stretching from Portland, Maine, to Montreal, and beyond that across Ontario.”

Voorhees said the Portland Pipe Line Corp. is wholly owned by Montreal Pipe Line Ltd., in which an ExxonMobil subsidiary holds a 76 percent majority stake. That subsidiary, Imperial Oil Ltd., as well as the 24-percent minority owner, Suncor Energy, are among the companies active in extracting tar sands oil in Canada, Voorhees said.

He said the parentage of the Portland Pipe Line Corp., as well as the meeting scheduled between LePage and industry officials, indicate signs of life for a plan to pump tar sands oil through Maine which PPL officials have long described as dead or dormant. That plan, originally hatched in 2008 under the project title “Trailbreaker,” called for the reversal of the Portland-Montreal pipeline to allow for the tar sands oil to be moved from Canada to Maine’s largest port and, by extension, international markets.

A call placed to the Portland Pipe Line Corp. Wednesday seeking comment was not immediately returned, but company treasurer David Cyr previously had told the Bangor Daily News a reversal of the pipeline would more likely be done to accommodate the transport of the less controversial crude oil — similar to what currently flows through the pipe — from western Canada.

The environmental advocates who held Wednesday’s news conference, however, maintained their belief that Portland Pipe Line Corp.’s global parent company has an interest in moving the thicker tar sands oil.

Nationwide, the debate over tar sands oil has largely centered around the Keystone XL pipeline, which is proposed to carry the controversial oil through middle America to the Gulf of Mexico.

On Wednesday, Environment Maine Director Emily Figdor invoked the imagery of past high-profile Exxon oil spills — such as the 1989 disaster involving the tanker Valdez off the coast of Alaska — to illustrate her group’s concern about ExxonMobil’s environmental track record and its ownership of the Maine pipeline.

She and Natural Resources Defense Council attorney Anthony Swift added that the transportation of tar sands oil is dangerous regardless of the company doing it.

“It has much higher acid content, much higher sediment content and much heavier molecules,” Swift said of the so-called bituminous oil.

As a result, he said, it must be diluted with toxic chemicals such as benzene and piped at higher pressures and heat levels than light crude to allow it to flow. That extra stress placed on the pipelines has caused increased leakage of the mixture, with pipes carrying tar sands oil shown to leak three times as much as pipes carrying traditional crude, he said.

And those leaks, Swift added, are much more damaging. He referred to a 2010 spill of bituminous oil in the Kalamazoo River in Michigan that environmental regulators said has “permanently” polluted 38 miles of the waterway and — at one point — raised benzene gas levels in the nearby air to 15,000 parts per billion. The exposure level at which humans can be severely harmed or killed, he said, is 9 parts per billion.

Environmentalists on hand Wednesday pointed out that the Portland-Montreal pipeline passes Sebago Lake, a significant drinking water source for southern Maine, and that the 62-year-old pipe is older than the one which broke down near the Kalamazoo River.

“It’s too late to save the Kalamazoo River,” Swift said. “But it’s not too late to save the rivers and waterways in Maine.”

In addition to the morning news conference, a public forum about the topic was scheduled to take place at 7 p.m. Wednesday, at Southern Maine Community College in South Portland.

Seth has nearly a decade of professional journalism experience and writes about the greater Portland region.