And one of the two founders of the Texan firm, Frederic Sewell, may well be involved in the final report to the parties to the Maui gas supply contracts.

"We are very pleased to have been selected for this project and look forward to developing an understanding of the issues on the Maui Field," said project leader Joe Spellman from the firm's Dallas offices.

"We are looking forward to working with the partners and to be sure Mr Sewell, who is involved in nearly every project, will be a guiding hand for this one too.

"While he won't be involved in the day to day matters, the final report will be referred to him," added the vice-president.

Mr Spellman declined to comment on the likely length or cost of the Maui redetermination contract, saying preliminary matters, including the exact scope of the project and precise number of staff, had yet to be finalised.

However, commentators say the Netherland Sewell appointment, its investigation and subsequent report could easily cost the Maui contract parties $NZ1 million or so. The parties would consider this money well spent, with up to 250PJ of gas, worth several hundred million dollars at today's prices, at stake.

Field owner Maui Development Ltd (MDL) shocked the New Zealand energy industry last November when it announced that Maui could be depleted by mid-2007 instead of the contracted 2009. It later asked for a formal redetermination - an effective re-allocation of remaining reserves between the major users - but then the parties called in an independent expert to settle this critical issue.

The parties to the Maui gas contracts - the New Zealand government, MDL, Methanex, NGC and Contact Energy - have also agreed that, in addition to deciding the level of remaining gas reserves, Netherland Sewell will consider any issues relating to the inadequacy of information provided by MDL, as claimed by Methanex.

Mr Spellman said Netherland Sewell had over 40 years of experience in a wide range of consultancy services, such as geophysics, geology, petrophysics, engineering, modeling and economics. The firm had also been involved in a number of field redeterminations, one recent case being the North Sea Markham field.

He said it was possible one or more of the project team members might fly to New Zealand for the redetermination project.

The Netherland Sewell report should bring to a close what could have turned into the most prolonged and bitter battle seen in the New Zealand energy industry for years. All parties to the Maui gas contracts have agreed to abide by the report's recommendations.