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• DIVISION OF MINERALS AND GEOLOGY Dcparlment of Natural Resources I a 13 Sherman SL, Koom 215 Dcnvcr, Colorado 802(1 f Nhonc' (3071 8663567 FAX 141111 ri12-ri106 February 6, 1996 Bear Coal Company Attn: Basil Bear P.O. Box 518 Somerset, Colorado 81434 • iii iiiiiiiiiiiuiii 999 STATE OF COLORADO ~_1a ~~ DEPARTMENT OF NATURAL RESOURCES Ruy Rumrr Governor lames 5 Lochhead Exec ulrvc Direc mr Michael B. Long Division DireUOr RE: Bear Mines No. 1, 2 and 3; File No. C-81-033; 1995 Subsidence Reports Dear Mr. Bear: The Division received various 1995 subsidence reports for the Bear Mines on December 13 and 21, 1995 and January 5, 1996. The December 13th submittal included first and second quarter subsidence data for Lone Pine Gulch, plus first half data for stations U10, U11, U21 and U22, along with slope stability data for the No. 3 mine. The December 21 submittal contained third quarter subsidence data for Lone Pine Gulch and the January 5th submittal contained fourth quarter data for Lone Pine Gulch plus second half data for stations U11, U10, U21, and U22. For future submittals, it would be very helpful if ~ each cover letter described exactly what is in the submittal. It is understood from reviewing the reports that the station U11 target pole was found bent over and the survey crew realigned the pole. The resultant change in position between the last reading prior to this occurrence and the current reading is a direct result of this event. It is also the Division's understanding that stations U21 and U22 have been relocated to nearby trees because the previous target poles had been destroyed. The change in base position of these monuments is due to this relocation and duly noted. The Division also understands that two new stations, U28 and U29, have been installed as required by technical revision 22 and baseline values have been established for these stations. These stations are not required to be monitored during the normal course of other required monitoring, unless visual signs of subsidence occur, which would then trigger a set monitoring schedule.