Kyle R., Gerardo M., Jeff B. 

Today we hammer-drilled (4) holes in the LVEA floor beneath CP2, (4) holes beneath CP1 and (2) holes beneath iLIGO RGA at NW corner of CP7.  Gerardo held in position a HEPA filtered vacuum at the hole site during the drilling to capture dust as it was being generated.  Following the drilling, the vacuum was left in position while a hand bulb was used to pump a jet of air into the bottom of the hole to liberate any remaining settled dust.  Jeff B. used a hand-held particle counter to monitor the operation at CP2.  At the next opportunity, I will use drop-in anchors to mount 1' lengths of unistrut to the floor.  These will provide a means to permanently mount 55 l/s ion pumps which will then connect to the vent/purge valves of CP1 and CP2.  These ion pumps will provide a means to pump hydrogen for those instances when CP1/CP2 need to be isolated for prolonged periods.  

This completes WP #6515