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n .~ ~~ 76. Sodium Adsorption ratio (SAR) values less than 18 should be acheived, The U.S. A. Handbook No. 60, entitled Diagnosis and Improvement of Saline and Alkali Soi defines saline-alkali soils as t ose w ose a ectroco uctivi y o e sa ura i extract is greater than 4 millimhos/cm. (4,000 micromhos/cm.) at 25 degrees .and the exchangeable-sodium-percentage (ESP) is greater than 15. Saline-alk i soils may exhibit soil particle dispersion, a condition unfavorable for t e infiltration and percolation of water and for tillage. The relationship between the SAR and the ESP of the receiving soils is shown on the attached figur Field experiments conducted by the U.S.D.A. Salinity Laboratory indicated ~at soil saturation extracts were 1 to 3 times as concentrated as irrigation waters applied. Waters with SAR values bet een 10 and 18 are classified as "Medium-sodium-water (S2)" the U.S.D.A. Salinity Staff. Agricultural Handbook 60 relates that: dium-sodium-water (S2) will present an appreciable sodium hazard in 'ne-textured soils having high cation exchange capacity, especially under low aching conditions, unless gypsum is present in the soil. This water may be ed on coarse-textured or organic soils with good permeability." The Medium-sodium-water limitation wa chosen as the heap effluent reclamation standard to be acheived, as it is under ood that direct precipitation upon soils will dilute heap effluent runon an ercolation as well as Frovide additional leaching of the affected soils. 77. Cyanide neutralization results of fresh Ovate column leach tests were not presented in Appendix I, as indicated in the Reclama 'on Plan (page E-12). Column leach tests conducted for reclamation/detoxific ion purposes should be analyzed for pH, electroconductivity, SAR, total and free cyanide, amongst metals and other parameters. Details of cyanide leaching p ocess simulation and detoxification methods, duration, and effluent results s uld be presented to the Division for evaluation of reclamation feasibiltiy and ,st calculations. Section E.3.5 Roads 78. Reclamation of roads should incorporate roads into the adjacent topography so that they become a part of the slope, rather than a re vegetated cut and fill structure. Please commit to such. Section E.3.6 Other Facilities 79. Fractured foundations and other similar facilities should be buried beneath at least three feet of earthern material prior topsoil reF~lacement for the same reasons outlined in question number 60. of this letter.