def METHOD_NAME(uncertain_time_delay=0):
    """
    test one time step with uncertainty on the spill
    checks there is non-zero motion.
    """
    pSpill = sample_sc_release(num_le, start_pos, rel_time,
                               uncertain=True)
    curr = c_GridCurrentMover(curr_file, topology_file)
    curr.uncertain_time_delay = uncertain_time_delay
    u_delta = _uncertain_loop(pSpill, curr)
    _assert_move(u_delta)