In July 2010, hundreds of buyers queued to buy land from as little as $230,000 in stage one of the $500 million, 2400-home Gregory Hills subdivision being developed in a joint venture between Dart West Developments, half-owned by the wealthy Perich family, and the landowners, the Marist Brothers.

AGL first lodged a major project application for its northern expansion, covering 20 coal seam gas well sites, in February 2009, tabling it at community consultation committee meetings with councils and developers in March that year.

Following widespread concern, including a 982-signature petition from the Scenic Hills Association, the proposal was scaled back and resubmitted in September 2010. Last November, AGL resubmitted the state significant project, which is on public exhibition until February, and has scaled back the northern expansion for a third time.

As Fairfax Media has reported, AGL now proposes to drill 66 wells at 11 surface locations in the Camden and Campbelltown local government areas and, although it does not plan to use hydraulic fracturing (or fracking), it will use directional drilling technology to extend the wells for up to 2.5 kilometres in a subsurface area below about 10,000 homes.

Many of the well sites are on lands earmarked for residential development. One, designated CUO2, is only a few hundred metres from homes at Gregory Hills, just across the road on an empty paddock that is to be turned into a business park.

AGL is understood to be in talks to buy part or all of the site. The company has declined to comment.

Andrew and Rachel Cartledge paid $245,000 for a 560-square metre lot in Lancaster Street in September 2010 and moved in with their two daughters a year later. The couple only learned of AGL's plans in April last year and wrote an objection to the Planning Minister, Brad Hazzard, and their local member, Chris Patterson.

After the revised project went on public exhibition, Mr Cartledge letter-boxed his neighbours at Gregory Hills. Most knew nothing of the plan. He spoke to Dart West and found out that it was opposed to AGL's plan.

"We didn't know when [Dart West] actually knew about it," Mr Cartledge said. ''Some people are saying they actually knew that coal seam gas was going to go in here before they started selling land to people, but it's not in any of our contracts. There was no information about it when we were actually buying the land."

Mr Cartledge is concerned about potential air, noise and water pollution and he is worried that not enough is known about the risks of coal seam gas extraction, including the potential for the kind of fires and gas leaks that arise in gas fields in Queensland. He is also concerned about the possible effect on the value of his home.

"This is pretty much our only investment,'' he said. ''It's our home, we've got a sizeable mortgage. We don't want to be tied to something that's going to drop in price."

Mr Cartledge said if a buyer had a choice between Gregory Hills and Oran Park, which does not have wellheads, "you'd have to say they would choose not to purchase here".

However, Mr Cartledge and his neighbours are wary of taking legal action against Dart West. ''We want this community to thrive. We want this project to be completed. [If] people say 'Hey, we weren't told about this and we're going to take you to court', obviously that's going to slow down the project. We've spoken about it with the neighbours and we all agree that would be the worst thing that would happen.''

At the nearby Hermitage project in Gledswood Hills, part of an 1800-lot development that includes the old El Caballo Blanco site, the developer, Sekisui House, took a different approach: it inserted a clause on the AGL gas project in all its sales contracts. The Hermitage went on sale last year. Sekisui, which has also objected to the AGL project, also declined to comment.

Dart West says that in 2010 there was too much uncertainty about AGL's intentions for the developer to make a meaningful disclosure to prospective buyers.

''We were aware there was a proposal. We took the view it was only a proposal, until it had any status, we were not in a position to accurately inform people because AGL … have been modifying their proposal repeatedly,'' the company's general manager, David Taylor, told Fairfax.

''At the time the original proposal came out there were no wells near where we were intending to sell. There was no impact on any of those lots.''

Dart West and Sekisui have lodged submissions opposing AGL's northern expansion at Camden. They have also asked AGL to relocate wells, and in at least two cases AGL has done so.

smh.com.au