Herb Chambers Mercedes-Benz UST and Gasoline Dispenser Upgrade
CommTank pre-inspected all equipment and materials (including a pressure test), installed one new 11,000-gallon (7,000 gasoline/4,000 diesel) double-wall fiberglass underground storage tank (UST) with 30-year manufacturer guarantee, installed tank supports and anchoring devices, installed two (2) 42” total containment sumps, installed approved backfill (pea gravel: naturally rounded particles with a minimum diameter of 1/8" and a maximum size of ¾"), installed Veeder-Root Tank Management System, installed spill and overfill prevention measures sufficient to fulfill the requirements of 527 CMR 9.00, installed Stage I Vapor Recovery System at fill port (Stage I system prevents escape of vapors during a gasoline delivery), installed double-wall flexible suction and connect to the dispenser, installed two (2) 2” schedule 40 steel vent pipes with approved vent caps, mount vent risers on existing building wall 12’ above ground level, pour concrete pad for new dispenser, installed 2 bollard located in front of dispenser, installed new gas/diesel dispenser with suction pump, gallon reader, hose and handle.
Each compartment was pressurized to 4 pounds per square inch (PSI) and held pressure for more than one hour. Vacuum pressure of –15 PSI was applied to the new secondary containment for the UST and held for over a 24-hour period. The primary containment on the product supply lines was pressurized at 50 PSI and held pressure for over a 24-hour period. The secondary containment for the product supply lines was pressurized at 4 PSI and held pressure for over a 24-hour period.
Fuel Management System
CommTank installed a Veeder Root ™ TLS 300C System, which is able to measure for liquid at the interstitial space (between the inner tank and outside containment). It measures the amount of gas or water (if any) inside the tank. It also triggers an alarm in case the tank exceeds its filling capacity. The system is able to detect if the underground feed and return lines develop any leaks.
After placing fuel in the tanks, satisfactory operation of the tank monitoring system was ensured prior to the system being placed into operation. Satisfactory operation of the secondary containment system and overfill prevention devices, impact valves and line leak detectors was also tested.