What would cause the plant to turn a light green to almost white at
the base of the plant?

I'm no expert, but I've been growing aloe vera for decades, and I'd
guess the plant has  been over-watered.  The other possibility is a
shortage of nitrogen.

If the leaves (spikes) are swollen or the stem is mushy, then it's
almost certainly too much water.  If not, try a little fertilizer.
Jobe's plant sticks are easy and help prevent overdoses.


You'll find detailed instructions on aloe vera care at: 
http://www.thegardenhelper.com/aloe~vera.html