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Mr. John Walters - page 3 . The exact inflow rate into the mine is difficult to calculate because of the unknown quantity of water stored in the mine sumps at any particular time. The total volume of in-mine storage varied between 1 to 1.5 million gallons. A total quantity of mine water, pumped out of the mine or used within the mine, at the end of each month between January, 1982 and January, 1985, was plotted (Figure 1). Although this graph does not represent the exact rate of water inflow into the mine with time, the general trend of water inflow into the mine can be observed. An interpretation of the presented graph indicates that from July, 1982 the water seepage into the mine was gradually increasing and peaked in February, 1983. At that time, two months after the mine progress was stopped, the mine inflow amounted to about 5.4 gpm. The estimated values of total water inflow into the mine per year, estimated inflow rates in gpd and gpm and an average inflow per month during a particular year are presented in Table 1. The presented graph of the water discharged from the mine does not indicate any significant seasonal variation of the water inflow into the mine. The generally low pumping rates during May, June and July of all monitored years could be impacted by summer vacation and a decrease in pumping. • The potential for evaporation of the water inflow into the McClane mine should be considered. Since evaporation potential can be very important to the evaluation of a water inflow- discharge, budget estimates of possible levels of evaporation could be made. The difference in temperature and humidity between the outside and in-mine environments typically causes condensation of water from the ventilation air in the mine during the summer and evaporation of in-mine water during the winter in temperate climates. With available average temperature and humidity data for outside and in-mine conditions, the probable amount of water removed by evaporation annually can be estimated. The results of such calculations usually show that the winter evaporation potential is greater than the summer condensation potential. However, in the McClane mine, due to the size of the underground opening, the evaporation potential would be limited. Source of Water Inflow The source of water seepage into the McClane mine can be interpreted by the occurence of water in the mine and by a comparison of water quality in the mine with surface and ground water quality data available for the permit area. The mine inspection and review of the mine inflow history indicated the following main sources of water inflow into the mine: • o water inflow related to the east fault; o water inflow related to the saturated part of the Cameo coal seam,