But the Pilbara stood out because 75 per cent of its emissions came just from diesel, its hefty fleet of 240-tonne haul trucks being the largest contributor.Back then, the company's internal documents show, BHP drew up a comprehensive plan to decarbonise the Pilbara mines Right now there's not much financial or political pain for BHP if it carries on using diesel in the Pilbara well into the next decade.BHP has already met its own company-wide target to cut its operational emissions 30 per cent by 2030