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By Mariya Gordeyeva
ASTANA, May 21 (Reuters) - Oil output at Kazakhstan's giantKashagan field may not resume until early 2016, Kazakh Oil andGas Minister Uzakbai Karabalin said on Wednesday, urging foreignpartners to start replacing leaky pipelines at the deposit.
Production at Kashagan, the world's biggest oil find in 35years, started last September but halted in early October afterthe discovery of gas leaks in the $50 billion project's pipelinenetwork.
The North Caspian Operating Company (NCOC), which developsthe offshore field in the Caspian Sea, said last month that itdid not expect to produce oil this year due to the leaks.
"It (production) may restart by the end of 2015 if all goeswell," Karabalin told Reuters on the sidelines of the AstanaEconomic Forum. "Otherwise, it may turn out to be early 2016."
Kazakhstan is the second-largest post-Soviet oil producerafter Russia. The government had originally hoped Kashagan wouldproduce 8 million tonnes of crude in 2014.
Citing the results of an investigation, NCOC did not ruleout that oil and gas pipelines might have to be fully replaced,a possibility raised by Reuters in April.
NCOC has identified stress cracking due to sulphur-ladengases as "the root cause of the pipeline issues" at Kashagan.
The field's oil is 4,200 metres (4,590 yards) below theseabed at very high pressure, and associated gas reaching thesurface is mixed with some of the highest concentrations oftoxic, metal-eating hydrogen sulphide ever encountered.
"The investigation is over," Karabalin said. "We are nowwaiting for proposals from the consortium members."
"We must receive their working plans, which would contain adetailed description of everything - when and what they willpurchase, who they will hire and how fast they will be."
Karabalin, formerly a professional oilman with decades ofexperience in the industry, said he believed the fullreplacement of the pipelines could take up to two years.
Much of Kashagan is built on artificial islands to avoiddamage from pack ice in the Caspian, which freezes for fivemonths a year in temperatures that drop below minus 30 Celsius(-22F).
NCOC includes Eni, Exxon Mobil, Royal DutchShell, Total, China's CNPC,Japan's Inpex and Kazakh state-run company KazMunaiGas. (Writing by Dmitry Solovyov; Editing by William Hardy and DaleHudson)
