We completed the 2nd wipe down of the upper sections of BSC-7. Work was slowed by the discovery of a mystery substance (Jodi calls it goopies, Mike L. calls it snot: see pix below) found during inspection.  It required special attention to remove as it was very tightly adhered to the chamber, in some cases appearing to be baked on. It seems likely that this material was left over from iLIGO install. We will continue to investigate. We ended the day by taking eight FTIR samples.