The gradual increase leading up to the most recent "bump" was the result of manually changing the HV of IP2 from 7000V (the nominal voltage for this pressure) to 5000V (not optimal).  The remaining perturbations are the reaction to us opening/closing pump isolation valves etc...  

It looks like I'll have time to do some leak hunting on this volume next week.  Also, I assume that we will be mounting Rai's "hydrocarbon" RGA to this volume soon.