What is the typical diameter of tank openings on underground tanks manufactured in the USA today?

The typical diameter of tank openings on underground storage tanks (USTs) manufactured in the USA today is generally standardized at 4 inches. This size is commonly used for various applications, including fill ports, observation ports, and product withdrawal, which are crucial for the safe operation and maintenance of the tanks. Standardization of the opening sizes helps ensure compatibility with the equipment and accessories used during installation, maintenance, and monitoring.

While there are larger openings available for specific applications or older installations, 4 inches remains the standard for modern USTs, aligning with safety regulations and operational guidelines established for the industry. This standardization is critical for preventing spills and ensuring the integrity of the storage systems throughout their lifecycle.