  The behavior of the residual (impurity-dominated) resistivity is computed for
a material near a two dimensional quantum critical point characterized by a
divergent $q=0$ susceptibility. A singular renormalization of the amplitude for
back-scattering of an electron off of a single impurity is found. When the
correlation length of the quantum critical point exceeds the mean free path,
the singular renormalization is found to convert the familiar
`Altshuler-Aronov' logarithmic correction to the conductivity into a
squared-logarithmic form. Impurities can induce unconventional Friedel
oscillations, which may be observable in scanning tunnelling microscope
experiments. Possible connections to the metamagnetic quantum critical end
point recently proposed for the material $Sr_{3}Ru_{2}O_{7}$ are discussed.
