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roof. The mining permit application does not identify any high volume aquifers in the overburden. The stratigraphic section overlying the mine is composed predominantly of siltstone, with some thick sandstone and interbedded shale and siltstone layers. Indication from the drill logs and from the mine permit are that the rock units are hard and well cemented. Surface subsidence related to water or ligiud withdrawal is typically associated with weakly to unconsolidated overburden. In this area unconsolidated deposits exist only or. the alluvial valley terraces. Therefore, water withdrawal from any aquifer within the overburden above the mine would not be expected to cause surface subsidence. In order to check the effects of water level changes on the shallow alluvial ground-water table, data from wells PAW-5, 6 and 7 were obtained from the permit file. The three wells are completed in the alluvial valley deposits. Data on river levels and monthly rainfall were also obtained. Figures 6 to 12 are graphic plots of this data. Figure 6 is a graph of the annual rainfall from 1979 to 1993. Of significance is that annual rainfalls for 1989 (10.79 inches), 1990 (14.7 inches) and 1991 (14.26 inches) were well below the average rainfall for the area (17.3 inches). A study of the daily rainfall versus water level for all three wells was conducted. It is clear that there is a rapid response (i.e., water level increase in the wells) as a result of rainfall in the area. One complicating factor is that the rain gage is located in Trinidad, about 20 miles away from the sample wells. Local thundershowers near the wells could produce fluctuations in the water level that may not be apparent if rainfall was not measured at Trinidad. Regardless of any variation in water levels caused by local versus regional rainfall events, the evidence indicates that the shallow alluvial wells are not being affected by the mining operations. If subsidence cracks had penetrated into the alluvial aquifer, it would drain the aquifer and the water level in the wells would be lowered or perpetually dry. The drought recorded in well PAW 7 is most probably related to very low rainfall (Table 9). Other Factors The three-year, below-average precipitation for the area could have caused damage to the structure because of trees drawing water from the soil zone. The distribution of trees around the structure (Photographs 2, 4, and 5) could be affecting the foundation by dewatering surrounding soils, followed by consolidation and differential lowering of the house slightly during the dry period of 1989 through 1992. 6