Starting 29 August, using an optical auto-level, I collected vertical position data at HAM3, HAM2 and the PSL area floor--see 38584.  On September 20 (post vent,) the HAM3 HEPI Pier Elevations were re-observed.  Bottom line:  No news, the floor did not tilt in any observable way: the four hepi piers moved up from 0.0 to 0.2mm.  While you could argue that this is about 100urads (depending on piers) it is also in the resolution of my measurements.  I closed the survey loop with just 0.1mm error but each observation is maybe +-0.1 or maybe even 0.2mm.  Again, bottom line, no big shift of the floor.

On 19 Sept, the HAM2 ISI Optical table (Stopped on Lockers) was observed with the auto-level.  The ISI table shows a tilt down from SW to NE of about 0.6mm or about 300urad over the ~2m table.  Looking at the CPS positions from before vent to now suggests the ISI has been operating at this attitude for quite awhile as there is only about 30-50urads of tilt from under-vacuum ISI isolated to vented ISI locked.

Attached are my surveying notes.