(a) A public entity shall, within one year of the effective date of this part, evaluate its current services, policies, and practices, and the effects thereof, that do not or may not meet the requirements of this part and, to the extent modification of any such services, policies, and practices is required, the public entity shall proceed to make the necessary modifications.

(b) A public entity shall provide an opportunity to interested persons, including individuals with disabilities or organizations representing individuals with disabilities, to participate in the self-evaluation process by submitting comments.

(c) A public entity that employs 50 or more persons shall, for at least three years following completion of the self-evaluation, maintain on file and make available for public inspection:

(d) If a public entity has already complied with the self-evaluation requirement of a regulation implementing section 504 of the Rehabilitation Act of 1973, then the requirements of this section shall apply only to those policies and practices that were not included in the previous self-evaluation.