I did some further google searching and came across the following post. Im not sure if we can post it here... Assuming we can if we make reference to its source... If not can admin delete please.
reference: whrl.pl/RcXpjt
posted 2011-Oct-15, 9am AEST
http://forums.whirlpool.net.au/archive/1771243
Andebrook wrote a reply to another poster Nuard... Its in colour on their blog...
Mate you are off on a few things here...
Nuard writes...
All product is carried in the same piping system, and tanks arent cleaned between product changes.
Refinery fed terminals use the same primary pipe into the terminal.
Once in the terminal, there is a pipe for every different base grade (G10, M91, M96, M98, E100)
Tanks are NEVER empty – safety, air, loss of suction – except for scheduled maintenance.
Nuard writes...
All fuel is exactly the same, comes from the same storage tanks and isn't separated into brands at all, same with Diesel (except Vortex diesel since it has an extra anti foam additive)
The base grade is the same – it has to be, it is an Australian standard and requirement.
The final product that gets pumped into your car is different for every grade for every company.
Vortex G10 additive is added at the terminal level also.
Nuard writes...
There is a difference however on the QC between the big three. Both Caltex and BP only pull test samples at the refinery level, Shell however not only pull samples at the refinery, but they also pull samples at all the major storage sites and do significantly more random checks at servo's.
It is an Australia requirement that all product must settle in tank at the terminal level and be sampled and tested prior to release to the gantry.
Refinery testing occurs to ensure that off-spec product is not sent down the pipe, as there is no way to pump back to a refinery (truck back only option).
Product MUST and DOES get tested at the terminal level as the spec changes once moved in a pipeline (mulitgrade pipeline provides low risk of contamination) – ie: conductivity in JET-A1 decreases with movement.
Nuard writes...
All the different fuel types use the same additive pack, feel free to look at the MSDS's of each product which lists whats in the packs.
Absolute rubbish.
As a driver you only have access to the gantry area and driveways of a terminal.
Mini-Pac additive pumps at the gantry provide no insight as to what additive is being put into each product.
If you had access to the tank farm, you would notice that there are multiple additive tanks throughout the terminal, each for a different grade for a different company.
All majors use COMPLETELY different additives in their products, this is what provides the point of differentiation and why majors spend money on R&D!
As for Vortex, you cannot pump an anti-foam additive (key word here) down a refinery pipeline for quality and contamination reasons – it is added at the gantry level when loading your barrells...