Hibernate query

I usually put my machine into hibernate mode when I am away from it for short periods of time. Since installing Win8 when I put the machine into hibernate I frequently find that it has come to life on it's on. I assumed that it might be "Wake on Lan" but I have not been able to find that option to change it. When I use search it says it cannot find anything relating to wake on lan.
Does anyone have any suggestions/directions to solve this? When I put the machine into hibernate I want it to stay there until I take it out, not pop back to life.
Thanks.