OREANDA-NEWS. December 21, 2015.  Congress is scheduled to vote Friday on a massive government spending package with a provision to lift all limits on crude oil exports, a potentially landmark policy change which would give US producers unfettered access to the world market for the first time in four decades.

While it remains unclear if the House and Senate will pass the bill, known as the omnibus, the White House has indicated that President Barack Obama will sign it into law if they do.

With so much hype over crude exports, which have been at the center of an intense two-year lobbying campaign, and the ever-changing nature of world oil markets, it’s a challenge, if not an impossibility, to forecast the effects of the possible policy change.

Still, here’s (almost) everything you need to know ahead of what may be a meaningful day on Capitol Hill:

Why would Democrats vote for crude exports now?

After sinking attempts this year to get two crude export bills to the president’s desk and months spent depicting an export policy change as a giveaway to Big Oil, congressional Democrats may have received an offer they couldn’t refuse from Republican leaders this week. In a series of closed door meetings and secretive negotiations, Republicans agreed to include a series of environmental-friendly concessions in the omnibus, chiefly five-year extensions of wind and solar tax credits. (For more about possible policy implications of bill, listen to this week’s special breaking news episode of Capitol Crude: The US Oil Policy Podcast.)

When will US crude hit the world market and how much is coming?

Theoretically, US crude exports could begin shortly after Obama signs the bill into law. Economically, that probably doesn’t make sense. A narrow Brent-WTI spread, which has averaged under \\$1.50/b so far this month, its lowest relational value in more than two years, makes most US crude exports uneconomic. The US Energy Information Administration maintains that if crude export limits were dropped, the US would likely export about the same amount of crude over the next 10 years than if those limits remain in place.

What about those East Coast refiners?

Since the debate over exports ramped up about two years ago, East Coast refiners were widely seen as having the most to lose from an export change. Bakken crude now shipped by rail to the East Coast, for example, may soon be more cheaply be sent by pipe to the US Gulf Coast and exported.

At the same time, shipments of Gulf Coast crude to the East Coast by vessel will still need to be shipped on Jones Act-compliant ships, which may be more costly than foreign-flagged vessels.

To address refiners concerns, Republicans included a provision in the bill which will expand a manufacturers tax deduction to cover 75% of an independent refiners’ crude shipping costs through 2021. The US Congressional Budget Office estimates that this new tax break could result in about \\$1.87 billion in lost federal revenue over seven years. Shipping by rail would be about \\$3/b to \\$3.50/b with the tax break, while shipping by pipe to the Gulf Coast would be about \\$8.50/b to \\$9/b, according to a Bentek analysis.

Could export limits go back into place?

Yes. The bill includes language allowing the president to require licensing for crude export during national emergencies, for sanctions purposes and during times of supply shortages and high domestic prices. It should be noted, the president retains executive powers to reimpose export limits as well.