Which of the following is important for maintaining tank integrity during backfilling?

Maintaining tank integrity during backfilling is crucial to ensure the structural stability and long-term functionality of underground storage tanks. The use of proper materials is essential because they provide the necessary support and protection for the tank. Appropriate backfill materials are typically lightweight and engineered to distribute pressure evenly around the tank, minimizing the risk of deformation or damage. Moreover, these materials should be free of sharp objects or debris that could compromise the tank's surface.

Utilizing correct backfill materials also helps in managing groundwater and preventing corrosion, which can lead to leaks and environmental hazards. This adherence to using proper materials not only safeguards the tank but also ensures compliance with regulatory standards, making it a vital aspect of tank installation and retrofitting practices.