  We present new results on the clustering and three-dimensional distribution
of radio galaxies from the Texas-Oxford NVSS Structure (TONS) survey. The TONS
survey was constructed to look at the distribution of radio galaxies in a
region of moderate (0 < z < 0.5) redshifts by matching NVSS sources with
objects in APM catalogues to obtain a sample of optically bright (R < 19.5),
radio faint (1.4-GHz flux density S_1.4 > 3 mJy) radio galaxies over large
areas on the sky. We find that redshift spikes, which represent large
concentrations of radio galaxies which trace (~ 100 Mpc^3) super-structures are
a common phenomena in these surveys. Under the assumption of quasi-linear
structure formation theory and a canonical radio galaxy bias, the structures
represent ~ 4-5 sigma peaks in the primordial density field and their expected
number is low. The most plausible explanation for these low probabilities is an
increase in the radio galaxy bias with redshift. To investigate potential
mechanisms which have triggered the radio activity in these galaxies - and
hence may account for an increase in the bias of this population, we performed
imaging studies of the cluster environment of the radio galaxies in
super-structure regions. Preliminary results show that these radio galaxies may
reside preferentially at the edges of rich clusters. If radio galaxies are
preferentially triggered as they fall towards rich clusters then they would
effectively adopt the cluster bias.
