That is completely fair, and Wash is right to be paranoid.

At first glance, though, the hot spring seems innocuous enough! The water is clear enough that he can see to the bottom; the spring is on the smaller side and deep, and the bottom seems to be porous and lined with large rocks — plenty of room for geothermal energy to seep into the water.

While inspecting, though, he'll also find a small tree stump with a stack of freshly laundered towels and a rather large plate of elderberry macarons. It seems a certain woman in charge has been using the springs as a silent retreat.

Or, maybe she intended for someone to find it — there are an awful lot of macarons.