Despite the differences discussed in the previous three paragraphs, both the analytical and numerical solutions describe heat depletion from a reservoir with the same volume and amount of removable heat. Conduction into the reservoir from the outsides is treated similarly in that they both use 1D analytical approaches. (Recall from Sec. 2.4 that in the numerical simulator the conduction into the reservoir is an analytical solution that is built into TOUGH2). The average temperature over the first 100 years is approximately the same for the base-case analytical and numerical solution, and the temperatures approach the same late-time steady state. Thus, it is possible to get an estimate of thermal depletion using both solutions.