craig
It means that if the seal is intact then there is a 90% chance of recovering at least 350bcf. Similarly there is a 50% probability of recovering at least 1.2tcf. But all this assumes that the exploration risks are zero, when in fact they are high at about 8 to 1. The exploration risks include a number of individual risks, the main one being the integrity of the seal. There are also environmental issues, which in the Fatherland are not to be underestimated, like what to do with the extracted water. However, all these things are solvable at a cost, but if the seal is not intact this becomes academic