Where is oxygen sensor system bank 1 located?

[xxniko90xx]

I'm getting a p1415 code and it's says something about bank 1 so I would like to replace that sensor but I don't know where it is located.

 

[bcworkz]

Front/Left is bank one. Note 2 sensors each bank, forward one is very important, rear one just verifies cat is working.

 

[xxniko90xx]

I'm sorry I'm just a bit confused. Which number in this diagram is System bank 1?

 

[Piper1]

In above pic it's labeled #1 closest o2 sensor to front of car, replaced this last week had e10 thrown was sensor ageing