We replaced tha O-ring on M20 at T2 and brought the target station down to vacuum, which allowed the target water pump to be turned on. 

After turning the pump on, we inspected the replaced valves for any leaks and found none - the flow on the demineralizing line was adjusted to 1.2GPM (also done at T1) by turning the needle valve.

Will observe till tomorrow to ensure that the T2 system is stable before proceeding with last system check.