On Sep. 3rd during the 6 hr maintenance day, Doug Preddy & I went into the 1A tunnel under “controlled access” to investigate a water leak that triggered the Water Detection Sensors. It was also noticed that the Cu-ALCW tank level was losing water.
Water was found to be leaking down the south wall chase where the T2 water package goes up the wall. Drip rate was ~1 drip every 15 seconds.
In the late afternoon of Sep. 9th;
Day one of the 1.5 day maintenance, the tunnel was surveyed by Fiona H. see RPG for field map & floor swipe results.
Doug, John McKinnon & I set up a plastic sheet with a funnel connected to a 8ft. lg. poly-flow tubing to direct leaking water from the T2 into the south gutter. This set up was left over night for the floor to dry up and resume the water leak investigation. See photos.
On Sep. 10th;
@ 08:30 about 70% of the 1A tunnel floor had dried up and the diverted water into the south side gutter had travelled to the T1 area.
The T2 cooling package was then turned off followed by valving off the Cu-ALCW feeding the T2 cooling package. A few more strips of red tuck tape were added to secure the temporary plastic diversion sheet.
@ 11:30 the x-strip graph (T/W MS 230) of the Cu-ALCW tank level showed that the leak had stopped and leveled off.
@ 13:15 the 1A tunnel floor had dried up with no water seen dripping from the vertical chase. Doug also mentioned that the “water sensors” that were activated reflected this. The Cu-ALCW was then valved back on to the T2 cooling package and within 3 minutes water began dripping from the south wall vertical service chase which now appeared to about 1 drip/sec.
Fiona took a water sample (20 ml vial) from the drips and also found ~ 1000 c/m (44-2 monitor) on the tacky mat just on the inside of 1A tunnel door. The 1A Tunnel and South TNF were then locked-up by Derek H., Violeta T. & Doug. The T2 cooling package was turned back on ok. Will try to repair this water leak during the Oct. mini shutdown.
 
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