What the heck was that all about???
From the source site:
A power arc to ground on the Low Voltage side of this substation creates an arcing fault that behaves like an uncontrollable welding torch from Hell, chewing up everything in its path. Protection hardware either fails to open the High Voltage side or is unable to sense the presence of the fault. Excessive current eventually causes the windings on the substation's power transformer to overheat, severely cooking its innards and causing the mineral oil inside to begin violently boiling. In a vain attempt to prevent the transformer's tank from exploding, pressure release valves vent clouds of superheated oil vapor which subsequently ignites and explodes in a ball of flame. A phase to phase short circuit occurs, perhaps caused by a flashover within the flames or a heat induced fault in the transformer. This causes an expulsion fuse to blow with a flash and a resounding BANG, finally killing power to the substation.
However, by this time, the weakened transformer's tank fails, and it spills hundreds of gallons of flaming mineral oil onto the already devastated substation. Local firefighters can only watch from a distance since there's no way to safely fight this fire, and the substation is a total loss. As one fireman quipped, "Firemen don't mess with their wires, and linemen don't mess with their fires". A very sobering look at the explosive power silently lurking within the quietly humming substation in your neighborhood...