Failure Evaluation of Savannah River Site High-Level Waste Evaporator 242-25H - Part I - 17366

(25H) in February 2016. Part I discusses the physical investigation to determine the nature and location of the leak site. Part II separately discusses the analytical work to determine the most plausible failure modes. The following investigation methods have been used to aid in determining the leak location: - Remote visual inspection: using remote cameras, inspection of both the inside of the evaporator pot and the evaporator cell, to see if leak locations are visible. Also, inspect the stainless steel insulation jacket for visible leakage. - Leak level check: filling the evaporator pot with flush water to determine at what elevation the pot stops leaking. - Enhanced remote visual inspection: utilizing dye penetrant on the inside of the evaporator pot, attempting to see if any defects in the primary containment are visible. - Grey Qb Gamma camera survey: to look for high radiation areas in the insulation of the evaporator pot. Parallel efforts are underway to develop a strategy for remotely removing the evaporator stainless steel lagging and insulation, locating the specific leak site and developing a repair method; and repairing the leak site if practicable. (authors)