smell of fuel

[520Ibmw]

Hi to everyone as I am new on here.

I was wondering if you could provide me with some advice on my 520I bmw 1990.
Basically I am getting a smell of petrol from the outside of the car and I have noticed that there is some kind of black liquid thing leaking just over the the exhaust.

I am thinking that this could be fuel hoses that need to get replaced or I am totally wrong?

Any help will be much appreciated.

Thanks.