Blackwater is toilet wastewater containing feces, urine and flushwater from flush toilets along with anal cleansing water (if water is used for cleansing) or toilet paper. It is considered to be contaminated, and cannot be indiscriminately dumped.
Greywater is wastewater generated from washing food, clothes and dishware, as well as from bathing, but not from toilets. Especially if biodegradable cleaning products are used, this water is generally benign and can be safely disposed of into the ground (e.g. as irrigation water feeding plants), but not dumped into bodies of water (e.g. rivers, lakes), where the contained nutrients can become pollutants.
“The main question i have is in regards to grey water and black water. I think being offgrid poses issues for disposal because holding tanks have to be emptied eventually…”
For the tiny home, blackwater can be handled through:
In small tiny home quantities, greywater can be run off into the ground. It shouldn't be stored for more than 24 hours, as pathogens can develop, turning it into blackwater.