  We consider microscopically low-temperature transport in weakly disordered
arrays of Josephson junctions in the Coulomb blockade regime. We demonstrate
that at sufficiently low temperatures the main contribution to the dc
conductivity comes from the motion of single-Cooper-pair excitations, scattered
by irregularities in the array. Being proportional to the concentration of the
excitations, the conductivity is exponentially small in temperature with the
activation energy close to the charging energy of a Cooper pair on a
superconductive island. Applying a diagrammatic approach to treat the disorder
potential we calculate the Drude-like conductivity and obtain weak localization
corrections. At sufficiently low temperatures or strong disorder the Anderson
localization of Cooper pairs ensues.
