1. A processing system configured to implement a distributed storage (DS) managing unit, the DS managing unit comprising: a computing core including associated memory; a network interface configured to couple the DS managing unit to a dispersed storage network (DSN) memory including a plurality of physical sites at which one or more DS units are located, the DS units storing encoded data slices associated with a storage vault having a number of pillars and a read threshold, the number of pillars corresponding to a first number of encoded data slices generated from a particular segment of data of a plurality of data segments of a data object, and the read threshold corresponding to a second number of encoded data slices, fewer than the first number of encoded data slices, the second number of encoded data slices corresponding to a subset of the first number of encoded data slices required to reconstruct the particular segment of data; and the computing core configured to assign storage of a particular encoded data slice to a particular DS unit included in the DSN memory based, at least in part, on a pillar associated with the particular encoded data slice, and on a physical site at which the particular DS unit is located such that at least one of the physical sites is assigned storage of encoded data slices associated with a plurality of pillars, and such that no one physical site is assigned storage of at least the read threshold number of the encoded data slices generated from the particular segment of data.