Funds appropriated pursuant to section 291j-8 of this title shall be available for grants by the Secretary for not to exceed 50 per centum of the cost of construction or modernization of emergency rooms of public or nonprofit general hospitals, including provision or replacement of medical transportation facilities. Such grants shall be made by the Secretary only after consultation with the State agency designated in accordance with section 291d(a)(1) of this title. In order to be eligible for a grant under this part, the project, and the applicant therefor, must meet such criteria as may be prescribed by regulations. Such regulations shall be so designed as to provide aid only with respect to projects for which adequate assistance is not readily available from other Federal, State, local, or other sources, and to assist in providing modern, efficient, and effective emergency room service needed to care for victims of highway, industrial, agricultural, or other accidents and to handle other medical emergencies, and to assist in providing such service in geographical areas which have special need therefor.