How do I subtract overtime/hours minutes from column and populate them in a new one in Power Query?

[PWil84]

I'm trying to get any hours or minutes over 8 into a new column in power query. How would I do this? Please see below:

What I have is one column that is Total hours:

 

[Alex Blakenburg]

Try this, in Power Query
1) Change data type of Total Hours to Duration
2) Then Add Column > Conditional Column
3) In the dialogue box enter a Column name and the conditions per the screenshot below, then hit OK