The use of proper backfill is critical to long term underground storage tank performance. Only approved backfill is allowed when installing fiberglass storage tanks and the backfill must meet ASTM C-33 for quality and soundness. To verify that your backfill material meets our specifications, use the Approved Backfill Calculator. Crushed concrete or limestone CAN NOT be used as backfill.
To begin: Select the backfill material you wish to verify. Then enter the required data from your provider’s sieve analysis and if your material meets our specification, you will receive a confirmation email from our Tank Technical Support department.