Proof of liability insurance in a minimum amount as set from time to time shall be posted with the village clerk by the sewer installation contractor or such person applying for a new sanitary sewer installation permit prior to the issuance of the new sanitary sewer installation permit. Should cash be posted instead of liability insurance, such amount shall be redeemed within 30 days after final inspection and approval of the sewer hook-up, which will be made by the department of public works superintendent or his designated representative. The amount returned shall be less the verified amount of damage committed to the existing sewer line of the village. Such verification shall be made by the department of public works superintendent. Should damage be committed to any village utility as the result of installation of a new sanitary sewer, the amount of damage committed upon such utility shall also be deducted from such amount and any remaining sum of money shall be returned as specified in this section. (Comp. Ords. 1987, §§ 25.303, 25.304)