The Region is issuing a Unilateral Administrative Order (���UAO���) pursuant to Section 106 of CERCLA, 42 U.S.C. �� 9606, for performance of a Remedial Investigation/Feasibility Study (���RI/FS���) and certain remedial actions in connection with Operable Unit 4 (���OU4 ) of the Palmerton Zinc Pile Superfund Site in Palmerton, Carbon County, Pennsylvania. The Respondents to the UAO are Viacom International Inc., TCI Pacific Communications, Inc. (collectively ���Viacom���), HH Liquidating Corp. (f/k/a Horsehead Industries, Inc.), and HRD Liquidating Corp. (f/k/a Horsehead Resource Development Company, Inc.) (collectively ���Horsehead���).
EPA sent Special Notice Letters to Viacom and Horsehead on December 22, 1995, offering them the opportunity to perform the RI/FS for OU4. The parties declined and EPA began performance of the RI/FS and an area-wide Ecologicial Risk Assessment using money from Superfund. Viacom has now expressed its interest in completing the activities necessary to finalize the RI/FS and Ecological Risk Assessment for OU4, including the performance of Interim Measures recommended by EPA in connection with the wetlands adjacent to the Cinder Bank (���OU2 ). Viacom has also indicated its willingness to remediate areas known a