The Mayor shall promulgate regulations which enable employees to participate in a voluntary tax-sheltered income deferment program which meets the requirements of § 457 of the Internal Revenue Code of 1954 , and the regulations and interpretations thereunder. The regulations shall include, but not be limited to:
(1) Provision for the receipt of the compensation deferred and for the use of such funds in accordance with any investment election permitted employees participating in the employee deferred compensation program;
(2) Provision for a contract agreement between the Mayor and any employee who desires to defer compensation under the employee deferred compensation program; and
(3) Provision for and limitations on the types of instruments, securities, accounts or other items in which compensation deferred under the employee deferred compensation program may be invested.