42 U.S. Code § 6939 - Domestic sewage
The Administrator shall, not later than 15 months after November 8, 1984, submit a report to the Congress concerning those substances identified or listed under section 6921 of this title which are not regulated under this subchapter by reason of the exclusion for mixtures of domestic sewage and other wastes that pass through a sewer system to a publicly owned treatment works. Such report shall include the types, size and number of generators which dispose of such substances in this manner, the types and quantities disposed of in this manner, and the identification of significant generators, wastes, and waste constituents not regulated under existing Federal law or regulated in a manner sufficient to protect human health and the environment.
(b) Revisions of regulations
Within eighteen months after submitting the report specified in subsection (a) of this section, the Administrator shall revise existing regulations and promulgate such additional regulations pursuant to this subchapter (or any other authority of the Administrator, including section 1317 of title 33) as are necessary to assure that substances identified or listed under section 6921 of this title which pass through a sewer system to a publicly owned treatment works are adequately controlled to protect human health and the environment.
(c) Report on wastewater lagoons
The Administrator shall, within thirty-six months after November 8, 1984, submit a report to Congress concerning wastewater lagoons at publicly owned treatment works and their effect on groundwater quality. Such report shall include—
(3) the extent to which such waste has been or may be released from such lagoons and contaminate ground water; and