The CHAP was some kind of Life Support structure in OP V1.5 and I believe since gas will become a mentioned resource that the CHAP may become nessesary. I think that the CHAP could be required for a colony that has a population of over 50 which we could say is taxing the CC life support generation systems.
Stats: ALL: CHAP
HP: 800
Armor: Medium
Ability: Allows for a colony to grow over 50 colonists (Produces air for 50 colonists)
Light Range: 6 tile radius
Size: 3 by 4 squares
Common Ore: 1300
Rare Ore: N/A
3rd Ore: N/A
Power: 40
Colonists: 2 Workers
Tube Connection: Yes
Also perhaps there could be a technology that increases it's production rate so each CHAP can support 75 people instead of 50.