Contractors undertaking excavation works at the site in Graham Street, were aware of one of the underground tanks but during its removal it was ruptured causing what was believed to be fuel to leak, while a second tank was also discovered.

Fire and Rescue NSW crews were called to the area after a strong odour was detected. With gas readings exceeding explosive limits, crews laid down foam to suppress the vapours. Worked was stopped on the site until the remaining fuel could be decanted from the tank and investigations made into the discovery of the second tank.

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An environmental site assessment made mention of an underground storage tank, but did not indicate what the tank might have been used for or when it had been installed on the site.

Bomaderry man Bill Kellett, who worked for a company based out of the location in the late ’60s and ’70s, has the answer to the mystery.

At the time Mr Kellett was working for a general cartage and furniture removalist company that later became Economy Express.

“The business was approached by a fuel company to also be a sub fuel agent at the location as well as running the transport operation,” he said.

“Part of the deal was that two fuel tanks would be installed on the site. One for diesel and the other petrol.

“My understanding was the two bases for the bowsers were still there somewhere.”

He said he believed at the time the owner of the property had sought approval through Shoalhaven council for the activity in addition to the other property use.

However, Mr Kellett said there was one problem with the site - water would often inundate the location.

“The buildings were safe because they were up off the ground but the water would often make its way into the tanks,” he said.

The site will be the home to the proposed Central Park residential unit development.

The buildings which were on the site, believed to be former military buildings, were brought to the location between 1961 and 1974 and used for commercial operations.

The site’s final use was for a pet store, a shop selling various homewares and a charity store, but prior to their construction the site was a vacant and undeveloped parcel of land covered by grass.