UPDATE 1-Chevron's Kazakhstan venture fined $307 mln

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ALMATY, April 18 (Reuters) - Tengizchevroil, a Chevron Corp-led oil venture in Kazakhstan, said on Friday it faced a fine of $307 million for violating environmental law at its main production site in the central Asian state.

"Tengizchevroil will challenge this decision," Kazakhstan's largest oil producer said in a statement. The company denied any wrongdoing.

Last year a Kazakh court fined it for the same amount of money after accusing it of violating legislation and damaging the environment by storing sulphur in big outdoor piles at the the Tengiz deposit.

Tengiz crude is rich with sulphur that needs to be removed before shipping.

Chevron (CVX.N) has a 50 percent stake in Tengizchevroil developing the giant onshore oilfield in the Caspian Sea. Other participants are Exxon Mobil (XOM.N), LUKOIL (LKOH.MM) and Kazakh energy firm KazMunaiGas [KMG.UL]. (Reporting by Mariya Gordeyeva; Writing by Olzhas Auyezov; Editing by David Holmes)