(a) The department shall charge a $50 enrollment fee to all participants in the Medicaid buy-in program. Upon payment of the enrollment fee, the first month's premium payment is waived. Medicaid coverage begins on the first day of the month following payment of the enrollment fee.

(b) The department shall develop a sliding scale of premiums for individuals participating in the buy-in program. The sliding scale shall:

(1) Be based on the annual gross income of the individual; and

(2) Provide for a minimum premium of $15 and a maximum monthly premium not to exceed three and one-half percent of the individual's gross monthly income.

(c) Subject to the minimum and maximum amounts described in this section, the department may annually adjust the scale of premiums charged for participation in the Medicaid buy-in program.

(d) The department shall biannually review the amount of the premium that an individual is required to pay under this section.

(e) The department may increase the premium required only after conducting a review.

(f) The department shall decrease the premium that an eligible buy-in participant is required to pay if:

(1) The individual notifies the office of a change in income or family size; and

(2) The sliding scale adopted by the department applied to the individual's changed circumstances prescribes a premium for the individual that is lower than the premium the individual is paying.

(g) The department shall establish administrative procedures regarding premiums for the buy-in program, including:

(1) The effect of nonpayment of a premium; and

(2) The collection of premiums.

(h) The department shall establish criteria to base the biannual redetermination of disability required for an individual participating in the buy-in program on the individual's medical evidence, including evidence of physical or mental impairment.

(i) In conducting the biannual redetermination described in this section, the department may not determine that an individual participating in the buy-in program is no longer disabled solely on the individual's:

(1) Participation in employment;

(2) Earned income; or

(3) Income from self-employment.