The Planning Commission shall forward copies of the preliminary plat to such officials and agencies as may be necessary for the purpose of study and recommendations. These may include the County Engineer and County Health District. After receipt of reports from such officials and agencies, the Commission shall determine whether the preliminary plat shall be approved, approved with modifications or disapproved. If a plat is disapproved the reasons for such disapproval shall be stated in writing. The Commission shall act on the preliminary plat within fifteen days after filing unless such time is extended by agreement with the subdivider. When a preliminary plat has been approved by the Commission, the chairman shall sign all copies and return one to the subdivider for compliance with final approval requirements. Approval of the preliminary plat shall be conditional upon compliance with all other applicable statutes, resolutions and regulations of the Municipality.