This is probably too late for Michael and Stephen but maybe helpful for someone.
The 'white container' is part of the salt dispensing mechanism.
It has a thread on it which passes through to the inside of the right side of the machine.
The white flange surrounding the blue salt level selector unscrews (I needed stilsons to get it off) and the top of the white container pulls free. Be careful not to damage the large rubber seal between the white container and the stainless chassis
All you need to do then is to free a little clip just inbetween the two leaky O rings and then pull the top container off the salt container.
The O rings on mine weren't split or hard but still leaked. I used a bit of plumbers silicone grease on mine to effect a seal and reassembled -- no leak!!
Gary Waite
August 2011