I'd sure like to know the reason they wouldn't use one of these bad boys to at least TRY and remove the nuts and bolts holding the flanges together. You would then have a nice clean flange in which to bolt a shutoff valve to. Unless of course they're not confident that this damaged BOP could withstand the pressure that would result if the flow was allowed to stop.
Unless of course they're not confident that this damaged BOP could withstand the pressure that would result if the flow was allowed to stop. They have already said they now for a fact the Well casing is damaged below ground, and they are 75% sure the well head is damaged also. If they stop the flow completely without cementing it they will have an even worse blow out than they already have.