The memo states, "That water supply department be allowed for payment of salary to such labourers directly on the consolidated pay basis i.e. as per last pay drawn considering their holidays, EPF and ESI and payment procedure will be fixed later on in consultation with accounts department."

This resulted in their salaries becoming Rs 4,281.60 after deductions unlike Rs 2,434 of other contractual labourers. However, Mr Maity denied such a memo and said, "As far as I know the wages have not changed."

"This will result in a demand to regularise the contractual staff and take them on KMC payroll in the future," said a KMC official.

"The remaining contract labourers will raise a furore when they come to know of this discrepancy," he added.

Sources also revealed that the private firm providing contractual labourers to the plant pulled strings which has resulted in this abysmal change.