(iv)On receipt of the monthly return along with Treasury Challan towards payment of cess, the Senior Mining Officer of the atom concerned, as the case may be, shall make a quarterly verification of the said returns, records maintained by the persons holding the area for mining operation in respect of ores or minerals removed and consumed from the leasehold area for each quarter ending on 31st day of Match, 30th day of June, 30th day of September and 31st day of December. As soon as possible on expiry of each quarter the Senior Mining Officer or the Mining Officer of the area concerned, as the case may be, shall send demand notice for payment of differential amount, if any, for the quarter, which should be paid within fifteen days of the receipt of the demand. The monthly cess remaining unpaid after the due date as prescribed hereinbefore, shall be charged with interest as prescribed in the Orissa Cess Act, 1962 and such interest shall be included in the quarterly return.