Subject to sections 300g-4 and 300g-5 of this title, national primary drinking water regulations under this part shall apply to each public water system in each State; except that such regulations shall not apply to a public water system-
(1) which consists only of distribution and storage facilities (and does not have any collection and treatment facilities);(2) which obtains all of its water from, but is not owned or operated by, a public water system to which such regulations apply;(3) which does not sell water to any person; and(4) which is not a carrier which conveys passengers in interstate commerce.July 1, 1944, ch. 373, title XIV, §1411, as added Pub. L. 93-523, §2(a), Dec. 16, 1974, 88 Stat. 1662.