> Edit: Another thought - perhaps next to my organic compost I will have a plastic compost where I layer old clothing, cellphone covers, food packaging along with some coal tar or old motor oil
You are making the same mistake so many people make: Plastics are not all the same. Each one is different, and something that can break down one will not break down another. You can not combine them this way.
> to break down into a bin of ... hell I have no idea what.
Most of those things would break down into water and CO2. Unlike soil, or food, plastics don't have many types of atoms: It's mostly just Hydrogen, Carbon, and Oxygen. Plastics are very clean.
You would be better off burning all those, the end results (the waste) would be identical, but you could capture the energy, instead of letting it get wasted as heat.
Some plastics, like Nylon, have nitrogen, but there's very little. It would probably becomes ammonia and evaporate, or be released a nitrogen gas. Some, like PVC, have chlorine, which would also evaporate.
Basically: If you did have some magical ability to compost plastic, you'd end up with water, with some harmless gasses being released.
To compost my vegi cuttings and yard clippings is to allow critters to eat it and leave behind their waste. Compost of organic matter is not magic.
By the same reasoning if critters evolve to eat plastic then the plastic becomes compostable. At the end of a compost cycle we would have a pile of their poop. It wouldn't be magic it would be "Bugs are evolving to eat plastic"
You are making the same mistake so many people make: Plastics are not all the same. Each one is different, and something that can break down one will not break down another. You can not combine them this way.
> to break down into a bin of ... hell I have no idea what.
Most of those things would break down into water and CO2. Unlike soil, or food, plastics don't have many types of atoms: It's mostly just Hydrogen, Carbon, and Oxygen. Plastics are very clean.
You would be better off burning all those, the end results (the waste) would be identical, but you could capture the energy, instead of letting it get wasted as heat.
Some plastics, like Nylon, have nitrogen, but there's very little. It would probably becomes ammonia and evaporate, or be released a nitrogen gas. Some, like PVC, have chlorine, which would also evaporate.
Basically: If you did have some magical ability to compost plastic, you'd end up with water, with some harmless gasses being released.