The purpose of this chapter is to establish and operate a centralized state collection and disbursement unit within the department of administration, division of taxation, child support enforcement for the timely, automated collection and disbursement of support orders being enforced under § 454(4) of title IV-D of the Social Security Act, 42 U.S.C. § 654(4), and in all cases not being enforced by the state in which the support order is initially issued in the state on or after October 1, 1998, and in which the income of the non-custodial parent is subject to income withholding.