Liability Insurance. Before a permit is issued, a certificate of insurance shall be required in an amount exceeding $1,000,000 naming the City as an additional insured for protection against claims of third persons for personal injuries, wrongful deaths, and property damage. The City officers and employees shall be named as additional insured. The certificate shall not be subject to cancellation or modification until 30 days after written notice to the City. A copy of the certificate will remain on file.