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• Brauner (1973) summarizes criteria used in various countries for allowable tilts and strains for different structures. He concludes that the various criteria are not always consistent. The SEH damage classification, which is shown on Plate 15, has been derived from observations of damage due to mining. It therefore expresses the combined effect of strain and curvature, even though only strain is used as an indicator of damage. The SEH classification relates damage to the length of the structure. Buildings under which mining will occur at the future mine are small and should not, in general, be especially sensitive to subsidence. Calculated strains indicate that appreciable damage could result at shallow mining depths, particularly at overburden depths of less than 500 feet. By the time overburden depth reaches 1,000 feet, expected damage is generally becoming appreciable to slight for the type of buildings of limited length present at the site. Potential damage to pipelines is indicated to be in the appreciable class of damage of the SEH. French er.perience (Brauner, 1973) indicates tensile strains as small as 0.0005 • or compressive strains of 0.001 to C.002 can cause visible damage to pipelines. These data indicate that precautions to minimize damage will be necessary wherever mining occurs beneath pipelines. Predicted impacts for individual structures, categorized according to the type of structure, are detailed below. Buildings Five of the nineteen buildings identified lie within zones of subsidence. The P1uckle Flo use (NW quarter of Section 13), the Morrell ranch, the Gross-Rhode cabin (SE quarter of Section 15), and an unnamed cabin near Morrell Cow Camp (SW quarter of Section I) all Iie at locations where several feet of subsidence due to future mining are predicted under the currently proposed mining plan. While the Muckle House, Morrell's ranch and Gross-Rhode cabin lie relatively close to the edge of subsidence zones, the unnamed cabin lies in the central part of a subsidence zone. A fifth, unnamed, cabin located on fee land (NW quarter of Section 19) lies above panel 15 off 8th East Mains. Extraction from this panel is comple*_e and no additional subsidence at this location is anticipated. Both the Gross-Rhode cabin in Sec- tion 15 and the unnamed cabin in Section 19 are uninhabited and ara in conditions of advanced disrepair. • - 49 -