After receiving the appraisal, the district shall provide the applicant with a letter or certificate setting forth the dollar amount of the credit, the reason for the credit, where applicable, the legal description of the site donated, and the legal description or another adequate description of the project or development to which the credit may be applied. The applicant must sign and date a duplicate copy of such letter or certificate indicating his/her agreement to the terms of the letter or certificate, and return such signed document to the district before the impact fee credit will be awarded. The failure of the applicant to sign, date, and return such document within 60 calendar days shall nullify the credit. The district shall notify the community development director of the credit so that appropriate conditions can be placed on the approved plans and permit.