The proposed project consists of approval of a Conditional Use Permit from the County for the development of a new production well, Well No. 3, and an associated pipeline to provide water to the USG Quarry. Together, these three project components are referred to as the “project area”. The development of Well No. 3, the associated pipeline, and the long-term operation and reclamation of the Quarry were part of United States Gypsum Company Expansion/Modernization Project (USG Expansion/Modernization Project). A Draft EIR/EIS was completed for the project in April 2006. On March 18, 2008, a Final EIR/EIS was certified by the Imperial County Board of Supervisors (Board) pursuant to the requirements of CEQA (SCH 200121133). As such, the potential environmental impacts of proposed Quarry expansion and reclamation and development of Quarry Well No. 3 were previously evaluated in the 2008 EIR/EIS. Additional land use entitlements from the County are not needed for mining and reclamation activities under the Quarry expansion. However, because Well No. 3 and the associated pipeline would provide water to support Quarry operations, the Subsequent Environmental Impact Report evaluated potential environmental impacts associated with mining and reclamation activities under the Quarry expansion, for full disclosure and to provide the appropriate CEQA compliance analysis and mitigation for responsible agencies. B-2 This Subsequent Environmental Impact Report evaluated potential environmental impacts associated with the Viking Ranch site restoration and Old Kane Springs Road preservation actions, as proposed in the Habitat Mitigation and Monitoring Plan (Dudek 2021). USG identified the approximately 207-acre Viking Ranch site for restoration and the 121-acre Old Kane Spring Road site for preservation to provide compensatory mitigation for the impacts to 139 acres of water of the United States at the Quarry. Although the Viking Ranch restoration and Old Kane Spring Road preservation will not require entitlements from Imperial County the Subsequent Environmental Impact Report evaluated the environmental impacts of these actions for full disclosure and to provide the appropriate CEQA compliance analysis and mitigation for responsible agencies.