was done on the site itself. The learned counsel submits that, even as per Notification No. 3 of 2005 issued under Central Excise Tariff Act, 1985 the goods fabricated on site of work used in construction at such site Tariff Item No. 7308 excise duty payable is nil. So also, the service tax is not payable on works contracts in respect of Dams which are specifically excluded under Section 65 (25) (B) of Central Excise Act. The learned counsel further submits that, while submitting the bids all inputs have been considered including Nil rate of excise duty. The learned counsel submits that, under the contract all Taxes, Duties, Cess etc. and payment thereof is the duty of the contractor and the petitioners have cleared their liability. The learned counsel submits that, while deducting the amounts no notices were issued to the petitioners and upon enquiry the petitioners were told that the Auditor has raised an objection that while preparing estimated cost excise duty was considered and therefore the contractors i.e. the petitioners have got undue benefit, as such, the amounts are deducted. According to the learned counsel, the deductions are unauthorized. The contractors do not have any access to the costing done by the Respondent / Corporation at the time of arriving at an estimated cost while issuing tender. Annexure - A of the tender lays down the description of the project, the details of the work and estimated cost. The estimated cost is stated in lumpsum. It does not specify calculation of excise duty separately.