Festival of Dangerous Ideas exhibition/installation in the cavernous foyer of Carriageworks will feature 80 works by eight Australian artists.

I’m watching a Hitachi earthmover bury a suitcase in a mound of dirt inside Carriageworks when my mind peels off on a surreal tangent: does the machine have job satisfaction? I happen to know that another machine on this job has an MOU with its human operator outlining fair work conditions, and I’m wondering if this excavator got the memo.

In fact, the Hitachi just buried the memo: 25 tiles bearing the text of a labour agreement between artist Sophie Penkethman-Young and the 3D printer she used to make them. This weekend, members of the public will dig them up as part of Heap: an unusual mix of exhibition, installation and “archaeological dig” featuring 80 artworks by eight Australian artists, commissioned by the Festival of Dangerous Ideas (Fodi). Taking place in Carriageworks’ cavernous foyer, it’s the centrepiece of a program of panels, performances and screenings inspired by this year’s theme: revelation.

During the installation process, I see a bronze mushroom, a canister of kangaroo apple and a spider costume buried under 120 tonnes of earth. Already interred: a human figure cast in hardened dirt, and a funerary urn. Each represents a “dangerous idea” – something “that has potential to change the world if taken seriously”, says festival director Danielle Harvey. Audiences are invited to “really get their hands dirty” in excavating these ideas, “as a prompt to think a bit deeply” about thorny issues such as climate change and colonisation.

Heap draws on a “very obvious metaphor,” Harvey concedes, but a powerful one. “We’re a country built on mining and excavating, so what we find in the dirt and the lens that we [put on it] – whether it’s interesting or dangerous, and how we value it – is super interesting in an Australian context.”