As used in this article, the following terms shall have the meanings indicated:
The recovery from industrial users of the treatment works of the federal grant portion of the cost of construction of the treatment works, allocable to the treatment of waste contributed by such users, as defined in the federal statutes and regulations. The portion allocable to each such user shall be payable in equal annual installments in the sum of 1/30 of said portion for a period of 30 years, after which said payments shall cease and come to an end.
The municipalities of the City of East Orange, the Township of Hillside, the Town of Irvington, the Township of Maplewood, the Township of Millburn, the City of Newark, the Borough of Roselle Park, the Village of South Orange, the City of Summit, the Township of Union and the Town of West Orange, organized in Joint Meeting pursuant to N.J.S.A. 40:63-68 et seq., under the terms of a contract dated June 1, 1926, as amended and supplemented, in the matter of a joint outlet and trunk sewer and treatment plant for the sewage emanating from said municipalities.