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The cross-sections show that the ground elevation for the majority of the stations has increased as much as four inches. This is because subsidence above panel two is causing a•cantilever effect that is forcing the surrounding ground to push up. The cross-sections also show as such as one foot of surface settlement in areas not predicted to subside. This is ex- pected since the monuments in these areas ere located on re- claimed spoil from strip mining. Surface settlement is shown in the cross-sections es areas where the change in ground elevation is uniform to a side of a subsidence brain. The end points for the angle of draw were determined incor- porating the definition for surface settlement written above. The definition wea adequate for determining end points on sides of the subsidence basin in rows S and NPR, but not in row H. The end point on the downdip side of the gob in row R could not be determined since its in an area where the affects of the cantilever action and surface set- tlement have not reached equilibrium. However, ao angle of drew for the downdip side of row R will be determined when row H has been undermined by the second Longwell panel. The angle of drew end end points locations are iiae~'followe: END ANGLE OF ROW POINT ---- DRAW ----- --- COMMENT ------------------ --- K - BSTWBEN -6.4 DEGREES UPDIP SIDB OF GOB R-19 AND H-20 S S-11 17.2 DEGREES DOWNDIF' SIDS OF GOB S 5-22 8.9 DEGREES UPDIP SIDE OF GOB NPR P-3 14.2 DEGREES BEHIND GOB The angle of draw and the maximum subsidence shown above are all within the predicted ranges submitted in Empires' permit. The permit predicted the maximum subsidence to be 8-feet and the maximum angle of draw to be 20 clegrees. The monitoring points will be surveyed again in September and December of 1986. Results from these surveys will be submitted in the next semi-annual report.