From Halopedia, the Halo wiki
Sector 24 is a sector in the city of Suraka on the planet of Carrow.
Sector 24 contained a collection of vertical farming facilities.
Sector 24 was not heavily attacked during the Voice of Maardoth's attack on Suraka during the Carrow Conflict, leaving it's vertical farms unscathed. As such, Surakan Militia Volunteers convoys were dispatched to these facilities to harvest the available food and transport them to Sector 31 in order to feed the refugees that had gathered there.