Three manual valves are closed on TCS water system return line in experimental hall. See attachments. It is for TCS TK2 water level slow drop trouble shooting.  These valves will be opened again right after troubleshooting.  

TCS TK2 water level no change(11.1 inches) in this week after valves are closed. I will keep these three valves closed for one more week.

I opened these valves. In two week times, The TK2 level dropped 0.1 inches. The water level change could be a result of evaporation of water in system. We will keep watching on it.