Entire city sitting on CSG reservoir

FIRST ON 7: Clashes over coal seam gas mining could soon be happening a lot closer to the city.

Experts say the whole of Sydney, from the mountains to the coast, is sitting on a vast reservoir of natural gas, and energy companies are determined to get it.

Cremorne Point is pretty, exclusive, and ripe for coal seam gas mining.

Documents held by the resources department show there's coal 900 metres under these expensive homes.

Part of the same field that runs under Campbelltown is currently the target of an AGL gas grab.

"If the O'Farrell Government approves coal seam gas extraction under houses around Campbelltown and Liverpool, no one is safe in Sydney from having coal seam gas extraction under their house," Opposition leader John Robertson said.

A state government report obtained by 7News suggests that the Opposition leader is right.

"The pause button should be pushed on coal seam gas extraction until we understand the science," John Robertson said.

Gas maps show almost all of the Sydney Basin has "desirable" gas-producing coal, but it's the corridor from Wollongong through Penrith, to Gosford, that promises the richest pickings.

It's described as having 'peak' CSG value, right under Campbelltown, St Marys, Windsor, Richmond, Woy Woy, even Palm Beach.

For many years CSG was seen as something for country people to worry about but recent moves by gas companies show Sydney, and its suburbs are squarely in their sights.

The CSG industry says wherever it goes, it's heavily regulated.

"We have very, very high standards in New South Wales, which we have to meet, and these include things like air quality and water etcetera,” the Australian Petroleum and Production Association’s Rick Wilkinson said.

The government says its hands are tied, because the Labor opposition granted the exploration licences when it was in power.

The O’Farrell government has extended tomorrow’s deadline, for objections to coal seam gas mining, at Campbelltown.

They’ll now be accepted for another three months.