It's been two months since BP's Deepwater Horizon oil rig started spewing toxicity into the Gulf of Mexico. And we're just now learning how the rig's last line of defense failed to prevent one modern history's biggest ecological disasters.


The video above, from the NY Times, outlines how Deepwater Horizon's blowout preventer—and more specifically, the "blind shear ram" designed to shut down the well in event of a blowout—was supposed to work, and why it didn't.


BP workers did try to deploy the blind shear ram by hitting the emergency button, but the system, designed with too few backup measures, did not perform as designed. Today, at least, it's impossible to know exactly why that is, but there's plenty of evidence showing that blowout preventers aren't the foolproof failsafe they're advertised to be.

It's a fascinating read, and part of the NYT's comprehensive overview of all aspects of the oil disaster, from a spill tracker to a detailed timeline of failed fixes. And, of course, an array of live video feeds to remind you how bad it continues to be.

Terrific coverage, to be sure sure. But let's hope it's not too long before they don't have to update it anymore. [NY Times]