Objective/Goals

Inspect, test and repair a dated 2,500L underground fuel system, restore to full functionality and provide compliance enabling support to this shopping centre in the event of a power-outage.

Problem/Issues

• The site’s ageing fuel tank had ongoing issues, and several investigations by other service providers had not found a cause or solution.
• Specifically, the underground tank had ingress of moisture and other contaminants into the fuel system significantly increasing the likelihood of failure to plant and equipment and ultimately compromising the safety of the buildings that relied on emergency generators.
• The contamination was at such a level that the system had to be isolated from the generators until rectified.
• Testing found underground fuel lines had perished and were leaking causing water ingress into the fuel tank.
• The tank was located in a high traffic commercial area with all works required to be done out of hours. Several unknown underground electrical and communication services were also in close proximity to the tank, so extreme caution was required during any works, especially excavations.

Solutions

• We conducted initial analysis of the tank and associated systems, then undertook integrity testing to identify the core issues.
• Based on initial results, we initiated surface excavation to expose the top of the fuel tank and isolate all external underground lines allowing the tanks to be tested individually. Utilising hydro excavation the system was uncovered without any damage to the fuel system or surrounding underground services.
• Through further isolation of external pipework, integrity testing revealed the underground tank was within standards and directed us towards an underground vent line that was the key issue.
• Further excavations were undertaken and new vent lines were installed using fusion welded Durapipe underground and all above ground lines with crimped stainless steel,
• The system was retested, approved for use and placed back into service

Outcomes

• Continuity of service and operations for this shopping and business centre, with an expedited project schedule.
• The underground fuel tank was restored for service, providing the on-site generator with a reliable fuel supply, and test certification validating the system is within EPA guidelines and standards.
• The additional identification and consequential safe removal and decontamination of old asbestos pipework and surplus building waste that had been buried on site decades earlier.