As soon as feasible, but not later than two years after the adoption of this Act, a Certificate of Compliance stating that a package or packaging component is in compliance with the requirements of this Act shall be furnished by its manufacturer or supplier to its purchaser provided, however, that where compliance is achieved under the exemption(s) provided in subsection 5, the Certificate shall state the specific basis upon which the exemption is claimed. The Certificate of Compliance shall be signed by an authorized official of the manufacturing or supplying company. The purchaser shall retain the Certificate of Compliance for as long as the package or packaging component is in use. A copy of the Certificate of Compliance shall be kept on file by the manufacturer or supplier of the package or packaging component. Certificates of Compliance, or copies thereof, shall be furnished to the [state administrative agency] upon its request and to members of the public in accordance with section 9.