to us once again what they are worried about could go wrong. >> reporter: well, they need to just by the name of the test. integrity testing. essentially what they're going to do in this test is close off all of the valves. you can imagine how intense the pressure with all of this oil shooting out into the gulf of mexico. we are talking about intense, intense pressure. when they cap that, all that pressure is kind of contained in there and they need to make sure that the cap that they've put on there will be able to withstand that and that everything down the line, deep into the earth, would be able to withstand that. obviously they're saying when you are dealing with this kind of pressure, if there are other problems that they don't know about down there, that this could actually cause further damage into that well bore and the casing, that pipe casing that goes into the earth and they don't want to cause any damage there because that can complicate things further. so that's really what they're trying to test. they're trying to figure out if they can even proceed with this integrity test to make sure that