Dug up soil

Underground Pass
Dug up soil is a piece of scenery found in the jail on the second level of the Underground Pass. There are two slaves and a crate in the jail. Railings must be picklocked to enter the jail, although an actual lockpick is unnecessary.

The soil can be searched:
 * under the soil is a tunnel
 * would you like to enter?
 * no, im [sic] scared of small spaces / yep, let's do it
 * you climb into the small tunnel
 * and crawl into a small dark passage

Plague City
Dug up soil is also found in the backyard of the Edmond's house. During the Plague City quest, players need to use 4 buckets of water to soften the soil enough to enter the Ardougne sewers.

Attempting to use a spade on the soil before it is soft enough will generate the message:
 * "you dig the soil The ground is rather hard"

After you soften the soil enough, when you use a spade on it you will receive the message:
 * "you dig deep into the soft soil 
 * Suddenly it crumbles away you fall through and land in the sewer 
 * Edmond follows you down the hole"