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Page 2 2.0 MINE PLAN AND AVAILABLE RESOURCE 2.I Mine Plan Figure 2-1 shows a schematic cross-section of the solution mining method used at White River Nahcolite, Inc.'s Wolf Ridge property. The new mining technique includes the submersi- ble pump in the production well, thereby, balancing the fluid pressure in the cavern and the fluid pressure in the surrounding rock. The mine plan includes multiple pazallel horizontal caverns de- veloped from long horizontal holes. The length of the cavems is controlled by the economics of long horizontal hole drilling and the available resource. Experience to date suggests that hori- zontal holes of 2000 to 2500 ft are viable. The spacing of the horizontal holes is not defined at this time for the new mining method. In the existing well field, four cavities are located 220-fr apart with the expectation of completing additional caverns between these existing wells fora fi- nal cavern spacing of 110 ft. In the new plan, where cavem stability is not a concern, the spacing of wells would be determined to maximize resource recovery and to maintain operational control. The overall mine plan includes solution mining from a panel of closely spaced horizontal holes with a barrier pillar of unmined material sepazating the panels. For this evaluation, a panel width of 800 ft and barrier pillar of 200 ft was selected. Long-term mine plans could include panels of different panel orientation to optimize resource recovery or to access resources isolated by property lines and/or resource thinning or replacement. The function of the barrier pillar is to isolate solution mining between panels, to limit surface subsidence, and to promote irregular rub- blization above the panel. The irregulaz rubblization is advantageous in aquifer protection and minability of the overlying strata to promote bulking into the cavern void. An alternate mine lay- out without barrier pillars would also be successful and would result in gradual and continuous deformation of the overlying strata. This too would be acceptable for aquifer protection and preservation of the minability of the "Mahogany Zone," but would result in higher surface subsi- dence, and for best results, complete or at least uniform recovery of the nahcolite (no remnant pillazs of unmined nahcolite). The former layout, with barrier pillars and hence irregular caving, was preferred because it offers greater flexibility in leaving intermediate pillars and no adverse structural effects of leaving unmined sections because of operational difficulties or halite intru- sions. Agapito Associates, Inc.