Upon full payment and performance of the Obligations (excluding only any liabilities which might arise in the future under the Environmental Indemnity), this Collateral Assignment shall become and be void and of no effect and, in that event, upon the request of Assignor, Agent covenants to execute and deliver to Assignor instruments effective to evidence the termination of this Collateral Assignment and the reassignment (without recourse) to Assignor of the Assigned Contracts and Permits and the rights, title, interest, power and authority assigned herein; provided, however, that any affidavit, certificate or other written statement of any officer of Agent stating that any part of said indebtedness remains unpaid shall be and constitute conclusive evidence of the then validity, effectiveness and continuing force of this Collateral Assignment and any person, firm, or corporation receiving any such affidavit, certificate or statement may, and is hereby authorized to rely thereon.