I have two currently abandoned in place circuits which are capped off and terminated in separate work boxes:

a) a 10/3 non-metalic sheathed NM-B 220V cable protected by a 30A CB which lands in the main panel,

and

b) a cable marked "E32071 3CDRS AWG6 compact AL Triple Alloy AA8176 Type SE cable Style U type XHHW 2 CDRS 600V" protected by a 30A CB which lands in a sub-panel.

Is there any way I can use either of these cables to split the hot legs and turn them into 20A 110V circuits? (Assuming I use the proper CBs in the panels).

I assume I cannot power a new sub-panel from the SE cable (and run my 20A circuits from the new sub) because it originates in a sub-panel and it is a 3 wire cable.

The 10/3 has no ground so, I think I am pretty limited here too. Right?

What I am hoping to accomplish is create a third 20A kitchen circuit (already have 2) to hook up to receptacles in a new island.

Any hope for me or do I have to put in a 12/2 homerun to the island from either the main panel or existing sub?

Alternatively, can I tie in the island circuit to an existing lighting circuit since I already have my two dedicated small appliance kitchen circuits in place?

Hmmmm - now that I think about it - I could tie the new island receptacles into one of the existing kitchen appliance circuits and just call it a day, couldn't I?

TIA

Doc