31.1 The Rio Colorado in Yuma, Arizona.; 31.2 Work and Beddome.; 31.3 Above the dam site.; 31.4 Phelps. Back water from the Gila and Colorado River. (MISSING); 31.5 Seven unidentified men standing near a car.
Aerial view showing site of Basic Magnesium's water supply intake at Lake Mead.
Transcribed Notes: Transcribed from front of photo: " Basic Magnesium, Inc., Acting for and in behalf of Defense Plant Corp. Plancor 201, Engineers LTD. Contractor, For water services, Las Vegas, Nevada, 12-30-41" Transcribed from photo sleeve: "Air view showing site of water supply intake. Intake structure and pumphouse to be built on point of island (at right center). Causeway between island and mainland in center. BMI, 12-30-41"