The county board may by resolution delegate the powers and duties enumerated in sections 383B.141 to 383B.1511, and those powers and duties necessary to the implementation of the purposes of central purchasing specifying the nature, scope and extent of the delegation. The authority and responsibility subject to delegation shall include, but not be limited to the following:
(a) purchasing and contracting for all goods, materials, supplies, equipment and contracted services, as provided in section 383B.143;
(b) preparation, review, modification and approval of all plans and specifications for goods, materials, supplies, equipment and contracted services;
(c) the transfer of any goods, materials, supplies, equipment or contracted services to or between departments, boards, commissions and agencies;
(d) selling or otherwise disposing of goods, materials, supplies, equipment and contracted services which are unusable or no longer required; and
(e) periodically reviewing and requiring department heads to supply necessary data concerning inventories and surpluses and monitoring compliance by department heads with purchasing laws, rules, regulations and procedures.
Notwithstanding the provisions of section 373.02, the county board may delegate its purchasing powers and duties to the county administrator. The county administrator, wherever referred to in sections 383B.141 to 383B.1511, may designate and delegate a purchasing manager or other person to perform the tasks empowered or assigned to the county administrator. Any purchase in excess of $3,500 shall require the signature of the county administrator or designee.