This project was for the completion of the Corrales Trunk Collector Pipeline Phase 3. We worked on improvements at Corrales well 2, Corrales Reservoir 3, and Arsenic Treatment System upgrades. This included the surge tank, well wash line air gap structure and automatic backwash stainer in a new CMU. Installation of electrical equipment for Well 2 in the surge tank enclosure. Installation of an 18-inch well collector pipeline from well 2 to an existing 18-inch well collector pipeline on-site during phase 1. Installation of a 14-inch PVC well washes line from Well 2 to an exiting well wash line installed on site. Well, 3 Site and Arsenic Treatment Systems Upgrades include demolition of existing piping on site; installation of an 18-inch well collector pipeline; improvements to the existing arsenic treatment system; construction of a new Reservoir 3 overflow drain pipeline; construction of 18” to 24” well collector pipeline from the arsenic treatment system to a new sodium hypochlorite injection vault; construction of a sodium hypochlorite building and on-site sodium hypochlorite generation system; construction of a carbon dioxide tank enclosure and carbonic acid injection system including a CMU carbonic injection system enclosure; construction of a new 24” well collector (inlet pipeline for Reservoir 3); installation of a PAX mixing system in Reservoir 3; site piping and grading; and electrical and instrumentation improvements.