Eskom is back at the negotiating table with Exxaro, this time over Matla Coal Mine, which requires R1.8-billion for its redevelopment. The power utility is reluctant to stump up the funds because the mine's contract expires in 2023.At Eskom's annual results presentation at Eskom Megawatt Park this week, Matshela Koko, executive head of generation, speaking on the sidelines said: "It takes two years to sink the shaft, so you will be done in maybe 2018-19, and then I spend between R1.8-billion and R2.8-billion and then you close [the contract] in 2023."Matla, the only remaining mine owned by Exxaro with production tied to Eskom, has three shafts.Shaft 1 was put in care and maintenance last year when Eskom refused to fund repairs to the mine's infrastructure. It was declared unsafe and closed.Shafts 2 and 3 are expected to produce about 8.5million tons against a contractual agreement of 10.1million tons this year, according to Exxaro, which initially wanted Eskom to spend R2.8-billion on developing the existing shafts, but has since reduced this to R1.8-billion.Eskom is trying to extract itself from several "cost plus" mining contracts with mining companies, including Anglo American and Exxaro. It has the mining rights and the assets belong to Eskom.Eskom and Exxaro are currently in dispute over Arnot Coal Mine. Last year, Eskom refused to renew a 40-year contract to source coal from the mine for Arnot power station because it could buy cheaper coal elsewhere.Eskom claims Exxaro charged R1,132 a ton of coal from Arnot Coal Mine, although Exxaro said earlier this year in its annual results it did not charge Eskom that amount . The dispute led to the closure of the mine, where 1800 jobs hang in the balance.Eskom and Exxaro are now thrashing out who is responsible for the cost of closing the mine.Matthew Shields, an analyst at Avior Capital Markets, said the Matla negotiation would not affect the outcome of the dispute between Eskom and Arnot Coal Mine."They are separate issues. The disagreements with Arnot mine are not going to be resolved soon," he said.Shields added that Matla still has up to 2034 and provided base load for Eskom, but because Eskom was trying to extricate itself from "cost plus" contracts, Matla remained at risk.After Eskom refused to renew its contract with Arnot Coal Mine, it went looking elsewhere for coal. We pay R1,600 a ton for Tutuka. It's unacceptable and we will go to unconventional suppliers and we will not apologise for that  CEO Brian Molefe said Eskom was down from seven to two the short-term contracts it had with companies - one of which is Tegeta Resources - to supply Arnot power station.Tegeta Resources, which bought Optimum Coal from Glencore in August last year after the mine went into business rescue, is owned by the Gupta family.President Jacob Zuma's son Duduzane is a shareholder.Molefe countered criticism that at R470 a ton Eskom buys coal from Tegeta Resources for more than the average price it pays for its short-term contracts, saying the coal is "export quality".He also defended the decision to pay Tegeta for the coal ahead of delivery."Tegeta said: 'We will mine it but we have a problem - we don't have the capital to restart those mines. We don't have the capital to restart those operations because bank accounts have been closed, nobody wants to give us credit.'"Several banks announced earlier this year that they would close the accounts of the Gupta family's Oakbay Resources and Energy. The family also a stake in Tegeta."We have no reason not to do business with Tegeta," said Molefe.Anglo American's New Denmark Colliery is facing a similar fate to that of Arnot Coal Mine.Eskom said this week that it would deal with coal supplies to its Tutuka power station the same way it had dealt with supplies to Arnot power station."We pay R1,600 a ton for Tutuka. It's unacceptable and we will go to unconventional suppliers and we will not apologise for that," said Koko.This week, Anglo American denied that Eskom paid R1,600 a ton for coal from New Denmark Colliery, insisting it paid only R668.Eskom said Anglo had failed to include the costs of operating a mine and the amortisation costs of historical capital expenditure...