Add to ORKGOn the basis of the underground water salinities in the model, full development of the irrigable area (about 75,000 acres). and delivery of all the return flow to Mexico could take place at the and of 12 years. If the additional acreage is developed earlier. the salinity of the water delivered to Mexico could well exceed 1,800 parts per million unless arrangements are made to allow part of the return flow to be stored until the salinity of the underground water is reduced to 3,200 parts per million. Further model tests are to be made with larger diversion rates and a more constant pumping rate. It is expected that these will show a satisfactory reduction in salinity within ten years. Reger Revells Cc: Under Secretary Carr Assistant Secret...