  We present VLT-UVES echelle spectroscopy of the HI and CIV absorption in the
spatially-extended Lyman-alpha emission around two high-redshift radio galaxies
0200+015 (z=2.23) and 0943-242 (z=2.92). The absorbers in 0943-242 exhibit
little additional structure compared with previous low-resolution spectroscopy
and the main absorber is still consistent with HI column density of ~10^19
cm^-2. This is consistent with a picture in which the absorbing gas has low
density and low metallicity and is distributed in a smooth absorbing shell
located beyond the emission-line gas. However, the main absorbers in 0200+015
are very different. The previous single absorber fit of HI column density
\~10^19 cm^-2, now splits into two ~4 x 10^14 cm^-2 absorbers which extend more
than 15kpc to obscure additional Ly-alpha emission coincident with a radio lobe
in these high-resolution observations. Although consistent with the shell-like
distribution for the absorption systems, 0200+015 requires a much higher metal
enrichment than 0943-242. The metallicity, inferred from the CIV absorption, is
considerably lower in 0943-242 than in 0200+015. We explain these differences
with an evolutionary scenario based on the size of the radio source. In both
sources the HI absorption gas originates from either a gas-rich merger or
pristine cluster gas which cools and collapses towards the centre of the dark
matter halo. The higher metallicity in the larger radio source (0200+015) may
be a result of a starburst driven superwind (concurrent with the triggering of
the radio emission) which has engulfed the outer halo in this older source.
