On October 23, 1981, the EPA announced the selection of 115 sites for the Interim Priorities List (IPL) as candidates for response action under CERCLA. The sites were selected by applying the version of the HRS referenced in section 300.65 of the proposed National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (47 FR 10991, March 12, 1982) and incorporating the States' designations of their top priorities. On July 23, 1982, the EPA announced the selection of 45 additional sites (the "Expanded Eligibility List" or EEL), under the same criteria used to establish the IPL. The EPA treated all sites on these lists as candidates for response or enforcement actions under CERCLA. The IPL and the EEL were informal lists used for internal administrative purposes in choosing initial response efforts, and are not part of the NCP.