Once considered pipe dreams, the concept of saving the Salton Sea by tapping ocean water from Mexico, to keep the accidental salt lake from drying up, will get an official consideration at two meetings in the desert this week. The California Natural Resources Agency will look at three competing proposals at a hearing in Coachella Monday evening, and in El Centro on Thursday. One group of engineers proposes a pumping plant in Mexico to lift the water 100 feet, 130 miles of canals, a four-mile pipe under the U.S.-Mexico border, and a power plant to generate electricity as the water falls 225 feet down to the Salton Sea.