a payment shall be in an amount determined by the Secretary, based on an estimate of the average costs of training for purposes of receiving a waiver described in subparagraph (C)(ii). Such a payment may be made only one time with respect to each such physician or practitioner. (B) Application In order to receive a payment described in subparagraph (A), a Federally-qualified health center shall submit to the Secretary an application for such a payment at such time, in such manner, and containing such information as specified by the Secretary. A Federally-qualified health center may apply for such a payment for each physician or practitioner described in subparagraph (A) furnishing services described in such subparagraph at such center. (C) Requirements For purposes of subparagraph (A), the requirements described in this subparagraph, with respect to a physician or practitioner, are the following: (i) The physician or practitioner is employed by or working under contract with a Federally qualified health center described in subparagraph (A) that submits an application under subparagraph (B). (ii) The physician or practitioner first receives a waiver under section 303(g) of the Controlled Substances Act on or after January 1, 2019. (D) Funding For purposes of making payments under this paragraph, there are appropriated, out of amounts in the Treasury not otherwise appropriated, $6 million, which shall remain available until expended. . (b) Rural health clinic Section 1833 of the Social Security Act ( 42 U.S.C. 1395l ) is amended— (1) by redesignating the subsection (z) relating to medical review of spinal subluxation services as subsection (aa)