- 21 - pressure between the wall and pit than would a hole filled only with air. Both these factors make the pit wall more stable. It also keeps the soil of the pit’s edges moist and therefore even more cohesive. Although some portions of the pit walls may well crumble over time, that crumbling is why the setbacks are needed. We also take judicial notice that the Houston area more closely resembles a swamp than a desert--there is plenty of water in the area to fill in the property when mining is done. We therefore find in favor of Terrene on this point, and agree with its experts that the pit walls can be left at a 75-degree slope. Ebanks credibly testified that at this angle, approximately 3% of the volume would be lost, so we will subtract another 94,643 tons.10 iv. Waste The final reduction we must consider is the waste that inevitably occurs during extraction and processing. Terrene makes no adjustment; the Commissioner wants us to use 10%. Neither side introduced any especially compelling evidence on this point, but we found Moritz credible in saying that some waste is inevitable in any mining operation and that 10% is the industry’s rule of thumb. So by a bare preponderance of the evidence, we side with the Commissioner. Using the 10 The math thus far: 3,899,696 - 248,310 - 496,620 = 3,154,766. 3,154,766 (tons remaining after setbacks and work area accounted for) x 97% = 3,060,123.Page: Previous 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 NextLast modified: November 10, 2007