Tracks are electrified in the New York City market. But diesel allows more torque which is why they are also often used on trucks so it can pull more. They could always build out an electric train that provides more torque.

But thats another issue. I presume they will be able to pipe the gas throughout the whole area. Streets aren't hard to run pipelines through. Natural gas lines have been replaced now with new PVC pipes in sections for a long time and they still likely aren't even fully finished.

It is a done deal and come September we will see Delta having access to more jetfuel.

While Delta is assuming they will save significant funds here, it is true they will still be subject to the fluctuation of crude oil prices. But in order to sustain their business they need to pay for jetfuel regardless. This way they will be getting access to more fuel since they will be refining more of what meets their actual needs.

http://upload.wikimedia.org/wikipedi...l_Reserves.png

I think Delta found the right method here to sustain its business for the long haul.