I assumed the hundreds of protesters who’ve come to D.C. to protest against the Keystone XL tar sands pipeline weren’t out there because they thought the Administration was on their side.  They meant to pressure the Administration over the environmental and political consequences of their imminent actions. Indeed, we now learn that at least one imminent actions may be a day away.

The State Department will remove a major roadblock to construction of a massive oil pipeline stretching from Canada to Texas when it releases its final environmental assessment of the project as soon as Friday, according to sources briefed on the process.

The move is critical because it will affirm the agency’s earlier finding that the project will have “limited adverse environmental impacts” during construction and operation, according to sources familiar with the assessment who asked not to be identified because the decision has not been made public.

The department will have to conduct one more assessment — of whether the Keystone XL pipeline is in the “national interest” — before making a final permit decision by the end of the year.

If the project is said to have “limited adverse impacts,” then the national interest question is more purely an economic one, and I can’t see this Administration denying the permit based on that.

At least 322 protesters have already been arrested one week into the tar sands protest, but it remains to be seen whether this news will amplify or depress efforts.  Only yesterday, the nation’s largest environmental groups announced unified opposition to the Keystone XL project.

I don’t know if the environmental impact is being measured merely on the construction of the pipeline or the impact of extracting and transporting 500,000 barrels of tar sands crude per day. We know that to extract the oil from the tar sands, forests must be destroyed, energy use must be expanded, and massive amounts of water have to be employed, similar to the amounts of water usage in hydraulic fracturing.

Canada has already released a report showing that greenhouse gas emissions from tar sands production would increase by one-third by 2020. As oil becomes more scarce, these more environmentally harmful processes to find energy get used, leading to a spiraling downward effect.   And the jackpot is often oversold; we just learned today that the Marcellus Shale has 80% less oil and gas than originally estimated.

That sets aside the potential environmental damage from leaks of the tar sands pipeline at any point across the 1,661 miles from Alberta to Texas. We’ve already seen leaks in the existing Keystone pipeline (the XL pipeline would carry the tar sands oil) on a dozen separate occasions in its first year of operations.

Kate Sheppard has a great breakdown of the relevant issues. But the State Department appears poised to issue their environmental report.