The facility, at Tomago, was delivered on time and on budget.

“It’s a vital asset for the Hunter region and will be used to support gas supplies during times of peak winter demand and if there is a major disruption to NSW gas supplies,” AGL CEO Andy Vesey said.

“The project team has done an impressive job of delivering, in less than three years, the large storage tank and all the necessary gas processing equipment, gas supply pipelines and electrical connection infrastructure.”

The 40m tank has the capacity to hold 30,000 tonnes – or 1.5 petajoules – of LNG.

“The cost of one day’s interruption to the region’s gas supply is estimated to be $5.5 million,” he said.

“The tank provides storage capability for up to two weeks of gas demand providing much needed energy security, particularly to manufacturers.”

The project did not record a single lost time injury during the 1.3 million hours worked.

The NGSF project made a major economic contribution to the Hunter region, employing more than 300 people during the construction peak in September last year.

Work started in August 2012 by major CBI Constructors.

The construction contributed an estimated $144 million, directly and indirectly, to the regional economy between 2012 and 2015.

A 5.5km pipeline connects the gas storage facility to the receiving station at Hexham.

AGL supplies natural gas to 700,000 gas users in NSW, including hospitals, schools, businesses and homes.

The company also operates the Silver Springs storage facility in a depleted gas field in Queensland’s Surat Basin.