  The mass transfer of interstitial impurities in a crystalline lattice under
the influence of the fast-moving deformation disturbance of the type of a shock
wave is considered. The velocity of the movement of the disturbance is supposed
to be compared with the characteristic velocity of the relaxation of the
diffusion flux to its local equilibrium value determined by the Fick's law. The
similar situation occurs in a number of experiments on the exposure of a solid
to dynamical external loads giving rise to such fast hydrodynamical processes
in a sample that the local equilibrium assumption, normally assumed for the
macroscopic description of transport processes, is no longer valid. Considering
the diffusion flux among the set of independent variables we have derived a set
of coupled hydrodynamic equations describing nonequilibrium behavior of a solid
in the absence of local equilibrium in the system. Within the scope of the
proposed model it has been shown that in comparison with the local equilibrium
system an enhanced mass transfer occurs under local nonequilibrium conditions.
