SRP materials testing information and data needs

The Savannah River Plant (SRP) will license and construct an underground repository in salt for HLW and DHLW. Waste package performance requirements are an essentially complete containment of radioactivity in the waste package for a period of 300 to 1000 years, and a controlled or limited release of radioactivity from the waste package and the engineered barrier system. Performance requirements are trivial unless the waste package is contacted by fluids. An advantage of a salt repository is its dryness, with limited fluids available for interactions with emplaced waste packages. The fluids that are present in salt (saturated brine solutions) are aggressive toward some of the waste package components. The fluids that might contact the emplaced waste package are water inflow due to failure of the sealing system, human intrusion, etc. Such fluids are referred to as ''intrusion brines'' and are generally expected to be NaCl-type brines. Water present in the salt include chemically bound water found in various minerals and clays, ''free'' or sorbed water (e.g., in clays), and brine inclusions. Solubilities of brine constituents generally increase with temperature