Its complicated but I would peg it at about 1/5th of a super tankers worth.
The Exxon Valdez carries 1.2 million barrels of crude. During the refining process a barrel of crude produces 19.5 gallons of gas, 9.2 gallons of home heating oil and diesel, 4.1 gallons of jet fuel, And a small amount of other products... See the Texas oil and gas association website for details.

This does not take into account the grid electricty used in the refining process ( between 7 to 12kwh) which is produced by buring coal and other nasty petro byproducts. ( a side note, the volt can actually go futher on the energy used to refine a gallon of gas, than an average car can on the gas).
So factoring in the energy used in the refining process gives you the 1/5th of a super tanker.

A good start but the US is currently importing 9.6 million barrels a day... and every day world demand goes up and the cost of finding and extracting goes up, the crude gets heavier and more costly to refine....

They also swallowed the cool aid on thinking that the cruse and volt are the same . They are not, the volt is a purpose designed EV. One look at the Volt and cruze side by side would have shown them this. They do share parts but not chassies although the cruze styling has obviously been influenced by the volt design ( which predated the cruze)

The volt is a purpose designed EV and that is has a low, well designed C of G compared to other sedans as the battery is inline with the engine/drive-train centre and it handles very nicely because of this.
It sounds like the author really wanted to take Aim at ford ( the Focus EV batteries are in the trunk, and not distributed properly in the car, which gives it an inferior weight and balance from the volt, leaf etc). Fords “Me-Too” car is obviously being built for fleet compliance issues and is not a serious contender. It is the only EV from the big auto makers that is not purpose built.

CR forgot the elephant in the room... SAFETY! The Volt is a purpose build EV derived from a 2007 concept car and the reason why the volt has its battery designed in a T shape and placed in the middle of the car is for crash safety. The skate board design used by the leaf and others does have a slightly lower C of G but is more prone to side impact crash damage and is more costly to repair ( if you get into even a low speed side impact accident the leaf and Model S batteries can be damaged cost thousands more to repair than the Volt).

reading the comments is the best part... but it also shows that we are doomed...

I hate to be the nerdy engineer in the pack, but the idea that the volt is coal powered and your normal car isn’t is simply incorrect. For the record, it takes between 7kwh and 12kwh of energy (including coal fired electricity) and the burning of other nasty petroleum waste products to refine an average gallon of gas. That means that the Volt can go further on the energy used to refine a gallon of gas than most cars can on the gas.
Then there is the issue of drilling, transporting, storage of both crude and refined product.

The idea that the volt creates more pollution by running on coal was actually started by a report commissioned by Toyota to help their Prius sales team. It was a tanks to wheels only study and did not look at the whole emissions lifecycle.