What does the term "fill" refer to in surface mining?

The term "fill" in surface mining specifically refers to the material that is used to fill in an area, which is often the case in practices such as valley fills or when restoring mined land to its natural state. After extraction processes, such as coal mining, the voids left in the landscape may require the introduction of fill material to stabilize the area and minimize environmental impacts. This practice is essential for reclamation efforts, where the goal is to restore the land to a condition that is safe and usable for future purposes.

This concept is crucial in surface mining as it addresses both operational efficiency and environmental stewardship, ensuring that areas impacted by mining regain ecological function and aesthetic value.