critical. we're following every moment of it for you on the surface of the gulf of mexico. brian, explain to our viewers, the delicate situation going on right now. >> wolf, there's a new sealing cap that bp is put into place as we speak. if this works like they think it might, then this main leak could be completely stopped, at least temporarily, for the first time in the more than 80 days since the spill began. taking a look now at the live pictures that we're seeing from the leaking well head site. we see some of the efforts going on now. this is the cap we're talking about now. this is the leaking well. by tonight, this new cap could be in place, called a three-ram cap stack. as of late this afternoon, it was about 40 feet away from where it will be installed. it replaces the old cap that was in place before. that cap was removed on saturday to make way for this new gap. that's why you're seeing the oil