; (iii) a community water system resulting from a joint enterprise between, or the combined operations of, one or more community water systems that receives a notice under subsection (b)(4)(A); or (iv) a contractual agreement unifying one or more community water systems that receives a notice under subsection (b)(4)(A) with one or more community water systems that has not received a notice under subsection (b)(4)(A). (B) Authorization A community water system that receives a notice under subsection (b)(4)(A) may enter into a partnership. (C) Requirement A partnership that includes a community water system with jurisdiction over a site on the National Priorities List developed by the President in accordance with section 105(a)(8)(B) of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 ( 42 U.S.C. 9605(a)(8)(B) ) shall include in the partnership agreement a plan developed by the community water system that describes how the community water system will— (i) meet the requirements of the partnership agreement; and (ii) with respect to the site, continue to meet the requirements under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 ( 42 U.S.C. 9601 et seq.). (D) Deadline for compliance A partnership shall be required to correct any significant noncompliance that resulted in a notice under subsection (b)(4)(A) to one of the entities in the partnership and to comply with this title— (i) in any case in which the State agency with primary enforcement responsibility under section 1413, or the Administrator, if the State does not have primary enforcement responsibility, approves a plan submitted by the partnership to bring the partnership into compliance with this title, as soon as practicable, but not later than the later of— (I) the date that is 3 years after the date on which the partnership is formed