Brazil\'s environment inspector fined Chevron Corp 10 million reais ($5.4 million, Dh19.83 million) on Friday for breaching the terms of the US oil giant\'s environmental licence when tackling an offshore spill at a well the firm drilled in November. The fine is on top of a 50 million reais charge the inspector, Ibama, slapped on Chevron for causing the spill at the Frade field when rock gave way due to a pressure surge. Chevron estimates 2,400 barrels of oil spilled into the sea. The fines pale into insignificance compared to the $11 billion lawsuit Rio de Janeiro state prosecutors are trying to bring against the company for a spill analysts consider fairly minor and one that never washed up on the country\'s shores. That action has raised concerns that unpredictable regulatory oversight could deter big oil companies from investing in Brazil just as it starts to tap vast new oil reserves of up to 50 billion barrels discovered in 2007. The so-called subsalt reserves lie about 7 km under the sea, making them technically challenging to reach as well as having potentially greater risks of causing a spill. Ibama said the latest fine was for the company\'s failure to adhere to the Individual Emergency Plan set out in the environmental licence it needs to operate. Ibama said Chevron lacked necessary equipment and was slow to respond to the leak.