The T2 cooling package was visually inspected today after blocks were removed.  With the cooling package off the following leaks were observed:

- Collimator A return line ball valve: ~ 2 drops / second
- Collimator B return line ball valve: ~ 1 drop / 3 seconds

The cooling package was then started and the following leaks were observed:

- T2 heat exchanger secondary side, north end ball valve (CuALCW):  ~ 1 drop / sec
- Target water return line ball valve above reservoir: very slow leak, wet but no drips visible

These leaks explain the water found in the tunnel, and the slow drop in T2 expansion tank level.  However it is a little mysterious why four valves all failed around the same time on two different water systems..

The copper active supply to the T2 area will be valved off to stop the leaks, and the valves will be serviced or replaced during this shutdown.