QGC tests the waters ...

Excerpt from an article in the Chronicle on 3 November 2006 regarding coal seam gas water:

QGC tests the water

Strategies in place to fix the long-term shortages

By Rebecca Vonhoff

Water is weighing heavily on Richard Cottee's mind.

The managing director of Queensland Gas Company (QGC), which explores and develops the coal seam gas resources of the Surat Basin, says a range of water-saving strategies has been introduced in the hope of overcoming long-term water shortages.

Water is an unwanted by-product when harnessing coal seam gas.

But QGC has applied to the Federal Government for a water grant that will, when coupled with capital from the company, allow for the building of a reverse osmosis plant that will supply Chinchilla with 3000 megalitres of water each year.

The water is reasonably brackish with 2000 ppm (parts per million) total dissolved solids (TDS).

"It's the kind of water that when I was young I would have put into the billy, thrown in some tea leaves and not worried about it," Mr Cottee said. "It's not incredibly high (in salt content)."

But once water passes through the reverse osmosis plant, the salt is eliminated. The 8000 ppm TDS discharge from this process can then be supplied to coal washing plants.

"This means we could supply Chinchilla with 100% of their potable water," Mr Cottee said.

"The Chinchilla weir is terribly low ... and obviously there's an enormous demand and I've always thought it's criminal to let water go to waste in evaporation ponds."

"We're custodians of the Earth."

In May, QGC also began a technologically adventurous plan to use the salty water for irrigation.

Usually salt is an irrigator's enemy, but QGC has devised a technique has the salt dropping to below root level after the soil has been ripped and calcium and sulphur added.

It is though that the soil would have to be rested every third season to allow for rejuvenation.

While Mr Cottee concedes the scheme is in its primary stages, so far the results have been promising.

"We're getting about two tonnes of barley to an acre," the managing director said, a figure that is better than the district average.

The technology is so new it has not been given a title, but Mr Cottee is quick to point out the technology has received no government support or funding.

While technology advances and grant applications progress, QGC has built dams.

"At the moment they're called evaporation ponds, but in time we hope to be able to call them surge tanks," Mr Cottee said, referring to an optimistic future that would result in a zero discharge site.

"We're trying to use the water in a manner that's beneficial to the region."