Don't know the specifics to your setup, here's how I try:

- EM, lightning shield

- 5x healing stream
- 1 wrath of air, three grounding totems, nature resistance totem (thanks to Ellay, see this thread)
- 1 totem of wrath, four searing totems
(sort of my standard layout)
- stoneskin, earthbind, strength of air, 2 earth elementals (this usually initiates the fight)

- bloodlust, trinket
- flameshock, lava, lb, lb etc.

I need to cross-heal after some 3 dmg casts; when one earth elemental is down I cast the next and so on.

When he becomes immune TAB over to his elemental spawn, that guy hurts. I may have to spread out to avoid some AoE damage.

He's level 78 and it's a tough fight for level 75 shamans, but I suppose he is well doable still. Had the "last" elemental phase down to 14%...
I'll keep trying and experimenting, for those nice q-reward boots alone^^.