[en] Analytical needs for LMFBR HCDA source term assessment are outlined and the physical events connected with the formation of an aerosol source are discussed. The important features of the movement of hazardous materials from the core site to the boundaries of the secondary containment are described, with accompanying brief reviews of prior work. The overall problem is broken down into tractable parts and approaches for attacks on the various problems are suggested. Topics include the state of the disrupted core, interactions with intact above-core structure, HCDA bubble formation, heat exchange with the sodium pool, aerosol formation by nucleation and fragmentation, attentuation effects, and aerosol behavior in secondary containments