Pipers' Parking?

I blipped this about three years ago but I am still none the wiser as to what it is all about so I decided to photograph it again. 
Is it somewhere people can go to practise their bagpipe playing as it is on waste ground right on the western edge of Perth beyond the bypass and well away from any houses. 
Or it may have something to do with a gas pipeline which years ago was laid somewhere nearby. I think that is the more likely explanation.