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EXHIBIT I - SOILS INFORMATION PARACHUTE LAYDOWN AREA The soils to be disturbed by the Parachute laydown area were characterized in terms of site conditions, the major soil, and sampled and analyzed to determine the depth of topsoil to be salvaged for reclamation purposes. Only the upper 24 inches of material was evaluated for use. The uppermost horizons have the most suitable tilth, roots, organic matter contents, and consistence for use as reclamation material. Because this area will be used as a laydown area, only the surface soils need to be removed and stockpiled. The general soil types found in the Parachute laydown area are the Arvada and Potts soil series. These soils occur with some inclusions on the broad alluvial fans. The remainder of the area is characterized by rock outcrops and shallow soils on steeper slopes. The Arvada series is a sodium affected, fine-textured alluvial soil. The surface horizon is predominately a sodium-affected clay loam, or bouldery clay loam and is 3 to 4 inches thick. In places the clay loam surface horizon is eroded. The subsoil includes an argillic horizon which generally has increased clay content and structure. The Potts series is a non-gravelly, moderately fine textured alluvial soil. The surface may be clay loam or stoney clay loam, and it may be eroded in some areas. It is predominantly platy, moderately fine-textured and ranges from 4 to 7 inches thick. The subsoils range from non-saline and non-sodic to moderately saline and moderately sodic. Following on-site investigation of the laydown area, the soils were divided into six soil map units for topsoil salvaging purposes. The soil map units and the average recommended salvage depths for each map unit are listed below. Map Unit Component Soils Average Recommended Salvage Depth Ar62 Arvada CL, eroded 6 inches Arab Arvada BD-CL 18 inches Ar-PoB Arvada CL, Potts CL, GR-CL 15 inches Ar-PoBs Arvada ST-CL,Potts ST-CL 18 inches Po-Ar6 Potts CL, Arvada CL 12 inches RLX Rock outcrop 0 inches The topsoil salvaged from the Parachute laydown area will be stockpiled in form~lla berm within the laydown area and will be revegetated using the permanent seed mix specified for the Parachute terminal facilities area on page E-36 of the original MLRB permit application. ~o• S~~Pi U,~~ 3~.~ :c/~, .~'~~ ~^ 1 v~. ~V/R l..l Gh of l /