After the Galactic Empire captured Ruul, it initiated extensive strip-mining operations across the planet. Within these newly formed canyons, the Empire established a number of mines that bored far into the exposed cliffs.
Following the Rebel Alliance's capture of the central computer complex on Ruul, they also gained control of various nearby mines. However, when Brenn Tantor spearheaded a campaign to oust the Alliance from the planet, these mines, along with the computer facility, were retaken.