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SE]Yf . 6Y TRIP REPORT 2-15-95';10~09PM 0 S M~ 303 832 8106;# 2/ 6 The purpose of this trip was to accompany the State of Colorado, Division of Minerals and Geology, in their investigation of a subsidence complaint at the home of Ann and Jim Tatum, Weston, Colorado. Personnel from the state included Jim Pendleton, Susan McCannon, Joe Dudash and Randy Price. Basin resources was represented by Ralph Lopez and Larry Bennett with Scott Harker, their attorney. The Tatum's Consulting Engineer Carl Gerrity was also present, Steve Parsons with OSM was present to address hydrology concerns. The complainants, Ann and d'im Tatum, believe that the subsidence resulting from underground mining operations at the Golden Eagle Mine by Basin Resources caused damage to their 90 year old two story adobe house. There is some questions as to the age of the structure, an engineering report by Carlton Gurity, PE states that, the residence is approximately 90 years old. The residents say that the home was built in the 1930'x. An inspection of the residence showed cracking at junction of walls and ceiling, cracks above the doors and windows, cracks at wall junctions and extensive water damage in the second floor bedroom. The exterior showed sign of water damage below a roof drainage trough and a large crack in the vicinity of the fireplace. All damage appeared to be above the foundation level. The sump in the basement laundry room contained water. There was water stains on the floor and two small (damp) water seeps in the concrete floor. The foundation appeared solid with no differential cracking or deformation. The foundation in the crawl space showed no. signs of distortion, deformation or movement. Jim Pendleton who examined the crawl space foundation supports reported that there appeared to be no movement or dislocation of the supports. Shims had been installed for floor squeak prevention or minor leveling. The closest approach of the Golden Eagle Mine to the Tatum home is the first north, room and pillar operation 350 feet to the southwest. This portion of the mina was mined with no pillar extraction'. Thirty-one percent of the coal was extracted from this portion of the mine using conventional methods. The permit application contains a safety factor analysis (pillar strength/pillar load) of 1.91. This analysis was done assuming a maximum extraction ratio of 50 percent. This stability factor was confirmed by OSM using the Surface Deformation Prediction Computer Model. A calculation of the safety factor using the same model and inputing the actual 31 percent extraction ratio resulted in a factor 2.5 (attachment 1). This is considered to be a stable configuration and will not result in panel failure. TATUMRPT.MIK 1