Well, I'm a big dummy. I've never owned an RV, but I did use to live on a sailboat, so my only experience with grey/black tanks was with marine pump out systems. My boat had a particularly difficult method to pump out, and rarely worked, and was a messy ordeal.
So I just assumed it was the same way with RV/Skoolie pump out stations. Because of my awful experience with my marine tanks, I wanted to avoid this whole situation on my Skoolie. So my design calls for a composting head, with urine being directed into the grey tank along with the sink drain.
Since we primarily use Argo for boondocking, I figured just dumping the grey tank prior to leaving whatever logging road we were on would be no different than taking a piss on the ground or dumping dishwater behind a tree (biodegradable soap and all).
However, thanks to some public shaming on this forum directed at me and my "genius" plan, I discovered there was something I wasn't considering: keeping urine and dishwater in a tank for days at a time allows it to ripen, and then dumping ten, twenty, thirty gallons of this ripe liquid in one spot is not
the same as just taking a piss behind a tree. And it's also disrespectful to the intent of Tahoe National Park (open for everyone, pack in/pack out, etc...).
On top of that, I now realize that using an RV dump station is nowhere near
the same as it worked on my sailboat. It's stupendously easy and simple. However, my tanks are already installed so I can't really change or add anything new. But maybe you could critique my new method and tell me what I'm missing:
The drain on my grey tank is a 3/4 ball valve (https://www.amazon.com/gp/product/B0764NBD7L/
), so can I just attach a 3/4 hose to this drain, put the other end in the dump receptacle, then open the drain valve? Then also turn the sink to flush out any remaining liquid? This is just a grey tank, so there won't be any solids bigger than the holes in the sink drain, so I think the hose size will be fine.