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PAR - C-80-007 - 2 - March 31, 1986 Avg' B. The Length of th e Screened Interval ~ ~ vpQ, y ~l1QtCoup,~~o ~ ~\ ` C. Depth of ,Well s E. The Location of the Screened Interval Above the Coal Seam. ~~i,OR3. Page 2-414 refers to Exhibit 2.8.2A which is a composite barren member well water level and spring elevation map. This map can not ^l pN~~~~a accurately represent the potentiometric surface of the overburden ~" DD aJ aquifer because all springs regardless of their source will issue G~~`Q' from the land surface, thus the elevation of the spring will be the 1.; ~~ ~;~c~levation of the land surface. A contour map drawn from the ~ ~ elevation of these springs will have the same contours as the land surface. Additional monitoring wells must be installed to further i"ti.'~, define the Potantrometric Surface, on either side of the divide. These wells should be completed identically, pump tested and monitored for water level. 4. Pages 2-415 to 2-479 contain ground water monitoring data as recent as 1980. Please include monitoring data that is more recent. 5. What impact has mining in the present 5 year mine plan area had on ,p.~_53~p the water levels in the water monitoring wells in the Barren Member. Most notably the wells installed above the test panels. If no effects were noted please discuss the reason for this. 6. Page 2-486 states that wells SOM-38-H-1 and SOM-38-H-2 were _a unsuccessfully pump tested using the air lift method. Why weren't Q other methods used to pump test these wells? Future wells should be pump tested with ultimate methods if airlifting can not be used. 7. Pages 2-530 to 2-536 are calculations for mine inflow using the Jacob and the McWhorter method. Given that the cone of depression will extend to .5 miles after 5 years of mining how much water can be expected to be removed from the Minnesota Creek Basin? 8. High rates of inflow were noted in wells along the Dry Fork of Minnesota Creek and Lick Creek. The Creeks in the North Fork Valley are known to be fault controlled. Since other mines in the North Fork Valley have experienced increased inflows while mining under creeks the wells may indicate zones of higher permeability. From data obtained from these monitoring wells how much mine inflow can be expected when these creeks are undermined? Additional wells properly installed along Minnesota Creek will aid in this determination. 9. Page 2-534 is a chart of projected mine inflows. This chart should be calculated for the life of mine. Also, inflows from faults should be calculated and included.