Antioch looks to use project stabilizing agreement for $60 million desalination project. The city has a $60 million desalination plant project about to hit the pipelines and is working on agreements to ensure it gets workers in a county bursting at the seams with large, ongoing construction. City Council members voted 5 to 0 on Tuesday night to pursue a project stabilization agreement (PSA) for the cityâs future brackish water desalination plant. A PSA is a pre-hire umbrella contract that consolidates wages, rules and disputes for a number of different contractors or unions on a large project. (LINK). HIWI042018-06-15T19:51:23+02:00