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Subsidence Profile <br />The accuracy with which the subsidence profile can be predicted is limited in mining <br />regions where there has been no previous measurement of subsidence profiles. The SEH <br />method can be used to obtain the general form of the curve, but the profile obtained will be <br />in error by an unknown amount. In the North Fork Valley extensive subsidence monitoring <br />over room - and - pillar mining has been done in the last decade. Both the Bear #3 mine and <br />the Bowie #1 Mine have monitored subsidence over workings which used room - and - pillar <br />mining methods. Tables 15 -2 and 15 -3 illustrate subsidence results measured forthe two <br />mines which are in different coal seams and the Bear #3 Mine has been mined in multiple <br />seams. <br />Table 15 -2 <br />Predicted Subsidence for the Bear #3 Mine thru July 1994 <br />Monument <br />Stations <br />Measured <br />Subsidence <br />" Predicted <br />Subsidence <br />Comments <br />UA1 <br />1.14 <br />1.7 <br />B &C -Seam on rib <br />UT2 <br />3.26 <br />6.1 <br />B &C -Seam on pillar <br />U1 <br />1.26 <br />1.8 <br />B &C -Seam C on rib <br />U2 <br />0.72 <br />1.0 <br />C -Seam on rib <br />U3 <br />0.34 <br />0.7 <br />B -Seam on rib <br />U4 <br />2.96 <br />4.9 <br />B &C -Seam on pillar <br />U5 <br />0.14 <br />0.4 <br />C -Seam on rib <br />U8 <br />0.40 <br />3.0 <br />B &C -Seam C on pillar <br />U9 <br />0.21 <br />1.7 <br />C -Seam on rib <br />U10 <br />0.64 <br />3.1 <br />B &C Seam <br />U11 <br />1.44 <br />1.3 <br />B &C -Seam on pillar <br />U21 <br />5.98 <br />5.6 <br />B &C Super - critical <br />U22 <br />3.48 <br />6.8 <br />B &C Super - critical <br />PR -14 - 9 - 03/14 <br />