  Verification solutions for uncertainty quantification are presented for time
dependent transport problems where $c$, the scattering ratio, is uncertain. The
method of polynomial chaos expansions is employed for quick and accurate
calculation of the quantities of interest and uncollided solutions are used to
treat part of the uncertainty calculation analytically. We find that
approximately six moments in the polynomial expansion are required to represent
the solutions to these problems accurately. Additionally, the results show that
if the uncertainty interval spans c=1, which means it is uncertain whether the
system is multiplying or not, the confidence interval will grow in time.
Finally, since the QoI is a strictly increasing function, the percentile values
are known and can be used to verify the accuracy of the expansion. These
results can be used to test UQ methods for time-dependent transport problems.
