A 2012 doomsday group which calls itself a “survival community” is building a concrete bunker at a secret location in the Tenterfield area.

Group organiser, refrigeration mechanic Simon Young, hit the national media this week when he offered $5000 seats in the bunker ahead of the doomsday the group is predicting for December this year.

Mr Young, a Tenterfield resident, told The Tenterfield Star that seven of the 20 seats had already been sold, to three families in Brisbane and Sydney.

Mr Young would not reveal details of the bunker’s location, but confirmed it was on 20 hectares of private land and was somewhere in the mountains.

The group’s website, which has had more than 29,000 hits, supports the belief there will be “massive earth changes” between October 21, 2012, and March 28, 2013.

Mr Young said he had come to believe in the theory through his own experiences.

“I had dreams of water coming in and catastrophes happening,” he said.

“A lot of my dreams have come true.”

He said he had researched the 2012 doomsday theory that predicts shifts in the Earth’s poles, massive earthquakes, the sinking of mountains and solar flares.

“This is something I guess that we are preparing for as an insurance policy - that would explain it,” Mr Young said. “People who get involved or become a member and actually put in money, then they have got somewhere to go.”

Overseas proponents of the Doomsday theory have said online that “survival in Australia will be highly unlikely”.

One December 2012 website says Australia’s mountains will collapse.

Mr Young is currently working on the bunker and said the $5,000 fee for adults and $2,500 for children went towards construction.

He said foodstocks were being gathered, there were shipping containers already on site.

“[We] are ready to crane into the bunker and [it] will be covered in 40 mpa concrete which is the highest strength available,” Mr Young said.

The doomsday theory holds no water with NASA scientists who have said December holds no great fears in store.

“Nothing bad will happen to the Earth in 2012,” their website states.

“Our planet has been getting along just fine for more than four billion years, and credible scientists worldwide know of no threat associated with 2012.”