Mr. Uma Shankar Tiwary, learned counsel appearing for the petitioner with reference to the agreement placed at Annexure-5 more particularly to Clause 6 of the Conditions of Contracts submits that a certificate is required to be issued by the Executive Engineer who is also referred to as the Engineer In-Charge, upon completion of the work by the Contractor and upon his removal from the area of the premises, all Scaffolding, surplus material, rubbish etc. as also the dirt from the wood work, doors, windows, halls, floors or other part of the building. If the Contractor failed to remove the said materials, the Engineer In-Charge was at liberty to remove the same at the expense of the Contractor. Clause 7 of the agreement required the Contractor to submit a bill in each month for the works executed in the previous month and the claim upon measurement being taken and found admissible would be adjusted if possible before expiry of 10 days of presentation of the bill. A final bill is to be prepared by the officers of the Public Works Department in accordance with the rules of Department in presence of the Contractor within the month of the date fixed for completion of the work as per Clause 8 of the agreement.