ISIL has captured at least 11 oil fields across Syria and Iraq and was understood to be making roughly £2 million ($A3.2 million) per day from sales in June. It has captured oil fields at Sasan, Ajeel and Sadid in Iraq plus Omar in Syria, along with large refineries at Fallujah, Aksas and Tikrit.
Iraq's largest oil refinery at Baiji, just over 209km north of Baghdad, has also been under siege since June and is thought to be ISIL's biggest source of wealth.
While the organisation has thus far retained trained engineers by threatening to kill their families, the strategy is starting to bite and ISIL has recently been using black market agents to advertise a £140,000 a year gig for a refineries manager position – the most senior of several vacancies the group is hoping to fill.
Dubai-based Manaar Energy head of consulting Robin Mills confirmed the reports, but believed ISIL would struggle to attract the best staff with the pay packet they are offering.
“The money is good, but it's not that good,” the Daily Mail quoted him as saying.
“A western oil exec posted to Iraq right now, let alone working for [ISIL], would expect to earn a lot more than that.”’
The problems don’t end there for ISIL, however, as it is struggling to find buyers for its product.
Washington-based consultant Matthew Reed, who analyses oil and politics in the Middle East, told CBC News last month that “no big traders, no serious companies are going to fool around with that oil”, which he said is “essentially radioactive at this point. No one wants to touch it”
Most of the sales, then, are going to so-called “middle-men” who own their own tanker trucks and who have connections to established smuggling networks in northern Syria and southern Turkey, or to local refineries in places like Syria, Iraq, Kurdistan and Turkey.
“They're relying on very small transactions and a lot of them in order to move the oil because they're selling it by tanker truck more often than not – and a tanker truck can't hold that much oil,” he said.