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9/5/13 State.co.us Executive Branch Mail - Fvvd: Response to Corley Co MW -NW The Boulay Report has some errors and omissions. On page 11 it states that the Corley Company well is located 800 ft. from the Southfield permit boundary, probably relying on the Southfield Mine Area Surface and Groundwater Hydrology map which has our well mapped in the wrong location. It has been demonstrated conclusively to DRMS that our well is, in fact, not only inside the Southfield permit boundary but that it was undermined with pillaring. The single statement that both Magpie and Second Alkali Creeks are unaffected by the Southfield mining activity is probably a result of relying on your hydrology reports that regularly show no flow; I do not believe that the Boulay Report states that Second Alkali Creek is not interconnected to Southfield mine workings. The reason for no flow at your SA -1 monitoring point on Second Alkali Creek is that this point is about 1000 ft. too far southwest and about 110 ft. higher in elevation than where there has been perennial flow in Second Alkali Creek for many years. It was apparently unknown by DRMS that there was continual flow in Second A Ikali Creek at the time of their hydrology report. I question your assumption that SF -87 -07 status is the result of caving action and crushing which broke the PVC casing above the mine workings thereby pinching off the casing's continuity to the mine workings. That might have happened or not, but I object to your conclusion that it is based on the fact that it happened at other monitoring wells. It is an assumption not of zet. Yes, we used a small volume of water to test the continuity of the casing instead of 1500 gallons of water. We were told by Janet Binns that the DRMS hydrologist has said that you should never have put that volume of water down MWNW. Yes, the two volumes used in each well are considerably different, but our test showed that the brief elevation increase from the five gallons returned to the pretest level which means that SF -87 -07 is not plugged. The BBA hydrology report may be correct about the Vermejo Formation being an aquiclude, at least in its undisturbed state. There is nothing in theirreport, however, that addresses the postmining situation with widespread subsidence. Even if entire pillared panels subsided en masse with no fracturing of the Vermejo Formation overburden over the center of the subsided panel, there would have been fracturing at the edges of the pillared area, and I really doubt that the entire pillared area of 2 North for example subsided as one giant block. The description of that area during the retreat gives a far different picture of very active roof and floor movement while the mining was going on. Didn't you lose a continuous miner in this process? There would have to have been considerable fracturing of the Vermejo Formation overburden rendering it quite permeable to vertical water transmission. Further, in my reading of the BBA report summary, their conclusion was that Southfield and the monitoring wells are hydrogeologicly connected. That conclusion was the basis for their recommendation that MW -23 and MW -65 are now adequate alone for the groundwater water monitoring. It was visually verified when the mines were still open that the seven mines including the Rex Carbon, Canon National, Double Dick, Black Diamond, Canon Chief, Corley, and Annex all interconnected. These mines were all in the top seamof coal above Southfield. All are full of water, and the water elevation in each is limited by the surface discharge in Second Alkali Creek - at least until the inflow into these inines exceeds the surface discharge outflow rate into Second Alkali Creek which may have a finite limit yet to he determined. Specifically, SF- 87 -09, MW -65, and the Corley Mine Well penetrate the working of the Double Dick, Black Diamond, and the Corley mines respectively. There were no stoppings or seals of these mines' interconnections. It follows that the static water elevations should be equal. Since MW -65 penetrated the Black Diamond void and is screened at that level, and since the BBA report says that MW -65 is hydrogeologicly connected to the Southfield workings, it follows that the flooded upper mines are also connected to the Southfield workings. In other writings I have presented some data and observations that would show that inflow fromNewlin Creek in the approximately one -half mine that it crosses the Southfield Mine pillared area with known subsidence overmuch of that area has greatly increased the inflow into the Southfield void in the past few years. Some drill logs available to me have the unconsolidated formation depths to solid formation: T132 at 35 ft., SF -87 -07 at 26.5 ft. of which 4 ft. is road fill, SR -63 at 11.5 ft., SF -85 -02 at 36 ft., and SR -64 at 27 ft. The drill log for SR -27 would be very revealing since it is about 110 ft. fromNewlin Creek, but since it is on Vento land I do not have that log. I do not think it is valid to claim that the Newlin Creek alluvium ranges from 50 to 100 ft. deep. I do not see a response to my request for immediate plugging of particularly SF -87 -07 with its defective casing and cap which allow surface water to enter that well. As opposed to your assumption for the cause of the partial obstruction of this well, it is possible that sufficient surface sediment has washed into the well in the 26 years that this well has been allowed to remain unplugged to cause the partial obstruction. Doug Corley https: / /mai l.g oog le.conVmai 1 /u /0 / ?ui =2 &i Ire29129fcb5 &�iev�-- pt &search =i nbox&th= 140ea06l931 a2742 2/3