Reply to: Open or closed? A discussion of the mistaken assumptions in the Economides analysis of carbon sequestration

This reply provides an opportunity to clarify one important point: although they might reduce the risk of the project, our paper was not meant to imply that CO2 storage can only be done in closed aquifers. Rather, we are pointing out that in projects involving injection with multiple wells in the same aquifer, resulting inter-well interference implies that each well has its own injection area with an effectively closed boundary. Bumblebee theories notwithstanding, our conceptual model matches rigorous simulation, and enables the fundamental observations that we have previously reported.