  Equation for the sum of BFKL pomeron fan diagrams is rederived by direct
summation and solved numerically for rapidities $y\leq 50$. At high rapidities
y>20 the resulting cross-sections for the scattering of a longitudinally
polarized $q\bar q$ pair on the nucleus cease to depend on its transverse
dimension and tend to a constant limit 0.1768 $R_A^2$, which corresponds to
scattering of a colour dipole on a black disk. Thus the unitarity is restored
and the singularity in the j plane is reduced to a simple pole at j=1.The
nuclear structure function at small x behaves as $Q^2\ln(1/x)$. The found gluon
density has a soliton-like form in the $\log k$ space: its form is close to
Gaussian, independent of rapidity, the centermoving towards higher $\log k$
with a nearly constant velocity as rapidity increases.
