Drillers have finally begun mobilising to start a campaign aimed at extending the life of New Zealand's oldest gasfield.

Kapuni, discovered 53 years ago and the field responsible for the birth of the country's natural gas industry, is to be the focus of new drilling for "tight" gas.

This is the industry term for natural gas deposits which are difficult to access because of the nature of the rock and sand surrounding them, and which require modern directional drilling techniques and fracking to get them to flow.

When the Kapuni drilling does begin, the target zones will be very deep. This has required Kapuni field operating company Shell Todd Oil Services to import a new rig from China which, when assembled, will be the biggest land-based rig yet seen in the country.

It will sit 50 metres tall, weigh more than 2300 tonnes, and have the ability to drill to five kilometres underground.

STOS has been forced to sit on its hands for several weeks waiting for an appeal period to lapse over the issuing of South Taranaki District Council land-use consents for the drilling project.

The deadline was Friday, and yesterday the Environment Court confirmed that no appeals had been received.

STOS general manager Rob Jager said his company would now immediately move into action.

"The first thing we'll be doing is setting up camp at the drill-site, and over the next couple of weeks we'll be transporting the rig down to Kapuni from its storage area at Port Taranaki," he said.

"Once the rig is assembled, we'll be doing a workover of an existing well, and then we'll drill two new wells. The whole idea of the project is to test the viability of the tight gas formations down there.

"We'll be testing the viability and the economics of it all.

"It's very exciting that we're able to do this in a field as old as Kapuni - it reflects how much technology has changed over the years."

Mr Jager confirmed that hydraulic fracturing - fracking - of the tight gas formations would be crucial to the success of the drilling. Fairfax NZ

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