Dublin city council estimates it will spend a further €600,000 on the Poolbeg incinerator project over the next five months on the assumption that construction will be going ahead.
In a letter to councillors, city manager Owen Keegan estimates that around half the money will be spent on consultants with most of the rest going on security and environmental site evaluation.
The council has already spent €96m on the Waste to Energy project and faces rulings from the EU on complaints that it contravenes rules on State aid and procurement.
Mr Keegan was responding to criticism from the council's audit committee that claimed the organisation of the project was still not fit for purpose despite criticisms contained in external audits up to one year ago.
In his reply, Mr Keegan said a Project Executive Board responsible for day-to-day running and a separate Project Board responsible for overall management were set up last week.
The €600,000 budget from February to June was also agreed last week by the Dublin Waste To Energy project board on the basis that construction of the plant will start in July.
This is dependent on EU complaints being resolved in the council's favour and a business case for the incineration project would then be presented to councillors.
Contracts for consultants involving payments totalling around €300,000 for commercial, technical and legal advice would then be tendered.
But Fine Gael councillor Gerry Breen criticised the late response of council management to criticism of the project's governance made by the Local Government Auditor last year and in a report from consultants Capita.
He said: "The council management cannot escape responsibility for the financial disaster of over €90 million being spent on the project to date. If this was the private sector heads would roll".
Meanwhile, Ireland is currently exporting 800,000 tonnes of waste a year because of the lack of incineration faculties.
Greyhound, the country's largest waste company, recycles 90% of its waste and exports it to Holland, Germany and Sweden where it is used to fuel power stations and in cement manufacturing.