The SNS provides an intense flux of neutrinos in the few tens-of-MeV range, with a sharply-pulsed timing structure that is beneficial for background rejection. The CEvNS process is cleanly predicted in the Standard Model and its measurement provides a Standard Model test; furthermore, the process is involved in supernova explosion processes and supernova neutrino detection. It also represents a background floor for dark matter direct detection. In the long term, precision measurement of CEvNS will address questions of nuclear structure. We aim to deploy multiple detector technologies in a phased approach.