  We present new Chandra Observatory observations with archival HST and radio
observations of 3C254, a radio quasara at z=0.734, and 3C280, a radio galaxy at
z=0.996. We report the detection of X-ray and possible HST optical counterparts
to the radio hot spots in 3C280 and of an X-ray counterpart to the radio hot
spot in 3C254. We present constraints on the presence of X-ray clusters and on
the magnetic field strengths in and around the radio hot spots. The spatial
resolution of Chandra allows us to show that these sources are not in hot,
massive clusters. The extended emission seen in ROSAT observations is resolved
into point sources. The IGM around these sources is demonstrably not dense and
hot. We conclude that radio sources are not reliable signposts of massive
clusters at moderate redshifts. X-ray synchrotron emission could explain the
radio, optical, and X-ray hot spot fluxes in 3C280, but it would require
continuous acceleration of electrons to high Lorentz factors, since the
synchrotron lifetime required to produce the X-ray emission is of order a human
lifetime. SSC with or without IC scattering of the CMB can also explain the
X-ray emission, but not the optical. We review all of the physical mechanisms
and summarize our current constraints on the magnetic field strengths in
andaround the hot spots of 3C254 and 3C280.
