A small leak has been found on TM4 Ta(-) which is marked as "B" on terminal blocks. The LD base Leak rate is 1.2XE-8 atm.cc/sec. 70psi helium has been applied to Ta(-) water line for 3minutes. The leak rate went up to 2.5xE-6 atm.cc/sec and stabilized there. Anders found a helium response on RGA helium reading during the same time. This confirms the leak is real. Other lines are leak checked today also. They are good still. All TM4 water lines were leak checked in ITE in 2017 January. They  were all good at 0.0 X E-9 atm.cc/sec. See attachment e-log.