Been reading the posts on here with, in some cases, bemused interest . Notably those where the drained fuel is returned to the tank. How much are you actually draining here ?. ..being an engineer, the short and only answer irrespective of the volume would be "no way ! "
I admit, I have had little to with GA over the years, but a lot to do with the airline world and the sample size did vary according to type, but even so, it was minimal.
As for the standards, I can think of two operators who would send the F/E down to physically check the bowser and aircraft sample before fuelling began, another sent a usually disgruntled F/O. To be frank, you can never do enough water drains on fuel tanks. As anybody who has encountered cladosporium resinae, ( that's the extent of my Latin ) inside a tank will confirm, the stench is never forgotten....and then comes the hard work.... inspecting for the corrosion and rectifying the damage.
A slight thread drift. but, on the subject of water and drains, the fuselage water drains are another function that need to be frequently emptied.....again, it's that old favourite silent killer, corrosion, that needs preventing. How many check those as well ?
I agree, that, in a different era as they say, disposal of the sample was to simply tip the sample jar down and onto the ramp....but that's long gone so you would think it prudent for any airport / airfield operator to provide a dedicated container to promote their green / eco credentials.