The operator must provide and maintain a performance bond, cash escrow or a letter of credit, in a form acceptable to the Township, to guarantee compliance with this chapter and the terms and conditions of the development agreement. The Township shall have the right to use the financial guaranty to remove stockpiles, complete site reclamation, and correct other deficiencies or problems caused by the operator, in the event the operator is in default of the obligations under this chapter. The amount of financial guaranty shall not exceed $10,000 per acre of the mining operation used for extraction, stockpiling, and processing activities. This amount may be increased by the Town Board with reference to the increase in the Consumer Price Index (CPI) for the Minneapolis-St. Paul Area. The financial guaranty shall remain in full force and effect for a minimum period of nine months or after reclamation or cleanup of the site is complete, whichever is longer.