The Glistening halls are the upper layers of the sewers / nearby mines. They tunnels are larger, and numerous. Further away the tunnels grow fewer and tighter leading towards the deeper mining areas and the underdark.

The mines were no longer turning a profit so they were reused as sewage waste pits for the town. There are gelatinous cubes here. They were placed here by the sewer crew guild. The guild carefully monitors the population of them.

The party might be hired to help with the survey.

Each cube has a silver plate embedded in it, with an identification number. Some smaller ones however have not yet been labeled, and need to have plates embedded in them using a 10ft pole.