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CONFIDENTIAL -2- On the basis of the information available to us on the proposal, we believe it would make a useful contribution to an over-all solution to the salinity problem. As the memorandum of the district notes, and was generally recognized at the meeting in this Department on the proposal, however, other measures would also be necessary. A brief restatement of the results of a solution which might be acceptable to Mexico might be helpful to you in indicating the extent of additional measures that would be required. As you know, the Mexican Government has insisted that it would not accept charge for any drainage delivered by Wellton-Mohawk that is not the result of salt balance. The Mexican and United States scientific panels were unable to agree on a report in June 1962 primarily because the Mexican panel desired that this be stated in the report. Nevertheless, the United States panel considered that the objective of salt balance at Wellton-Mohawk was reasonable and provided the basis for a scientific solution. This objective is implicit in all of the panel's proposals. CONFIDENTIAL The Mexican Government has pressed for a solution which would result in a year-around salinity index below 1,300 p.p.m. The United States panel, for its part, considered in its studies the generally accepted criteria established by the United States Department of Agriculture, i.e., that water with a salinity of above 1350 p.p.m. is dangerous for agriculture. We, of course, have consistently refused to discuss the problem with Mexico in terms of a maximum level of salinity because of the well-known and strongly held view of the Basin States that the United States could not give Mexico any guarantees as to quality. But it should be noted that if near salt balance conditions were established at Wellton-Mohawk, the salinities of water delivered to Mexico would be below 1300 p.p.m. Relating the Wellton-Mohawk proposal to these general criteria and principles, I would conclude: 1. Additional measures would have to be adopted that would reduce winter salinities another 600 or 700 p.p.m. We have no doubt that Mexico would consider as completely unsatisfactory winter salinities of 2000 p.p.m.Epson Perfection 4870 Photo, 400 dpi, 8 bit, 1,648,337 byte