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• <br />• <br />• <br />General Salvage Recommendations <br />It is often assumed that bottomland soils are rich and excellent. This is not a safe <br />assumption, especially when soils are salvaged in a mining operation. Some bottomland soils, <br />because they are exposed to strong capillary rise of water and continued sedimentation, can <br />exhibit highly undesirable characteristics after salvage even though prior to salvage the <br />vegetation appears to be excellent. In some cases, saline soils may have achieved stability with <br />the salts leached to deeper layers and less saline soils near the surface. This will often allow <br />species that are not usually considered to be salt - tolerant to inhabit a soil that, after salvage, <br />becomes salt affected through mixing of the saline lower layers with the less saline upper layers. <br />Soil salvage on this site should be done with considerable care and when questionable <br />soils are encountered those soils should be separated from more adequate soils. In general, <br />questionable soils on this site tend to be more clayey with the silty and sandy soils being much <br />safer to use. Clay soils should be tested for salinity and sodium. Sodium is not so important to <br />test for, but if the salinity is above 7 to 9 mmohs /cm then an SAR test should also be done as the <br />soil is potentially sodic as well as saline. <br />Unsuitable soils should be used as backfill materials and should be placed deep in the fill <br />rather than near the surface where the salts can move upward to the surface through capillary <br />action. <br />The ideal revegetation soil appears to be a silty to sandy loam with minimal clay <br />component, an SAR of 10 or less, and salinity of less than 6 mmohs /cm at 25t. <br />Experience in Phase 1 has not shown significant indicators of problem soils. <br />3 <br />