An anonymous reader writes with word that BP has announced the Gulf oil spill has been stopped. Another reader adds more detail: "The last valve on the new cap has been closed, and the flow of oil and gas into the sea has stopped. That doesn't mean it's over. It is unclear whether the steel casing deep in the well can contain the pressure. The risk is that it could burst, which would eventually cause a rupture on the sea floor that would make things much messier to deal with. However, they're monitoring the pressure buildup carefully and if the pressure holds over the next 48 hours (indicating there is no leak below the sea floor), they'll assess what to do next. If it doesn't hold at the expected readings, then they'll re-attach the pipe used for producing to the surface and start collecting again. Regardless of what happens the relief well still has to be completed to permanently plug the well with cement, which could take a couple more weeks."