6.—(1) Where any amount of a levy is not paid by the due date for payment specified in the demand issued under regulation 3, the constituent council shall be liable to pay to the joint waste disposal authority interest, calculated in accordance with paragraph (2), on the amount of the levy issued under these Regulations which remains unpaid after the due date for payment.
(2) The interest payable under paragraph (1) shall be simple interest calculated from day to day on the unpaid amount from the due date for payment until the date when payment is made at a rate equivalent to 2 per cent. above the highest base rate quoted from time to time by any of the reference banks.
(3) For the purposes of paragraph (2) “reference banks” shall be interpreted in accordance with paragraphs (3) to (5) of regulation 10 of the 1992 Regulations (interest on unpaid levies).