What were they doing on Ronika?

In the Fall of the Sith Empire comic series, Jori Daragon is arrested for shipjacking, and is sent to the arid planet of Ronika, which is being turned into a colony to serve on a chain gang type of operation. But what are they doing there? Im not sure whether theyre digging those little slab things out of the ground or sticking them in the ground. And what are they anyway? Its never really explained.

 

Nobody knows...

 

Digging. Most likely they were leveling terrain for a settlement, or else they were quarrying building materials. Another possibility is that they were quarrying raw carbonite.