Different weight percents of natron in the regolith in the salty ice-table system affects the retreat rate calculated in 5 K temperature intervals to different depths. The time delay spans several orders of magnitude, from 1 yr (top contour), all the way through to 10 Gyr (bottom contour). At the lowest temperatures, for the highest salt contents, the salt could extend the lifetime of the ice table in the near surface to almost that of the universe.