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'r PLAN TO SALVAGE SEASONALLY SATURATED SOILS NEW HORIZON MINE CMLRD PERMIT N0. C-81-008 The Permit Revision No. 2 of Nucla Strip Mine (now New Horizon Mine) stipulated that the Operator submit specific plans for salvage of seasonally saturated soils to be stripped in the course of strip mining of coal. This document outlines such plans including timing and season of salvage operations and techniques used to ensure that soils will not be saturated at the time of salvage. Timing of Salvage The topsoil at the proposed New Horizon Mine gets saturated with water during the irrigation season. The irrigation water is supplied by Colorado Cooperative Ditch Company of Nucla. The normal irrigation season lasts between mid April and October 1 of a given year. The irrigation ditch stays dry during the rest of a year except for five days in November and five days in March. It has been observed that the land in question is the driest during March/April of a year. Western Fuels - Colorado will, to the extent feasible and practical, conduct the topsoil stripping operation during non-irrigation seasons, preferably March/April of a given year. However, if topsoil stripping is necessary during other times, it will be done in accordance with the plan to ensure that soil will not be saturated at the time of salvage. This plan is explained in the succeeding paragraph. Plan to Ensure Unsaturated Conditions of Soil Pursuant to communication with CMLRD personnel, Western Fuels - Colorado's consultant determined that the topsoil that would be salvaged at the New Horizon Mine should be stockpiled with a moisture content less than 1/2 bar. During personal communication with Mr. Tony Waldren of CMLRD in June 1992, our consultant discussed the soil sampling techniques and sampling locations. It was decided that placing a few monitoring locations in areas with similar slopes and soil types would be adequate to determine when soils were dry enough to stockpile. Exhibit "A" shows the five categories of soil types that occur in the permit area and proposed moisture sampling locations. Western Fuels - Colorado proposes to use soil moisture probes or tensiometers at each sample location. The tensiometers consist of a ceramic block that absorbs water from the soil. After these blocks have been buried at a specific depth for 48 hours, the moisture in the block should be in equilibrium with the moisture in the soil. An electronic instrument to measure this moisture (in negative bars of pressure) can then be attached to the wire leads that extend above the ground surface.