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ERHIBIT I <br />DORCHESTER COAL MINE <br />SUBSIDENCE CALCULATIONS <br />FOR <br />PARACHUTE PIPELINE COMPANY <br />A.) A graph of over burden depths (h) vs maximum subsidence (S) <br />(Exhibit II) was prepared. This assumed a 12 foot mined seam <br />(m). Maximum subsidence (S) was based on s/m values obtained <br />from Fig. 3 of the Subsidence Engineers Handbook. <br />B.) Subsidence profiles for the maximum predicted subsidence for <br />each of the panel widths investigated (Exhibit III). <br />C.) The elongation of the subsidence profile was calculated and a <br />strain based on the original distance is shown below. The <br />strain based on the Pythagorean theorm is also shown below and a <br />ratio of subsidence strain to Pythagorean strain. <br />w/h SUBSIDENCE PYTHAGOREAN <br />STRAIN STRAIN <br />350 = 1.75 <br />200 <br />-3 -4 <br />1.415 8 10 5.876 8 10 <br />500 = 2.5 <br />200 <br />700 = 2.33 <br />300 <br />-3 -4 <br />1.445 x 10 5.450 x 10 <br />-4 -4 <br />6.834 x 10 2.584 x 10 <br />RATIO <br />(STRAIN SAFETY <br />2.41 <br />2.65 <br />2.65 <br />D.) An assumed axial strain safety factor of 2.75 was used in the <br />stress model. <br />