Now that I think about it - the game's story is not related to the jam's theme: "harvest". The rules of the jam require that the theme is present in some way.
Mining is different from harvesting. Mining involves extracting non-renewable, geological resources (like minerals, metals, and fossil fuels) directly from the earth, whereas harvesting refers to gathering renewable, biological resources (like crops, timber, or fish) that grow and replenish over time.