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.:. - III IIIIIIIIIIIIIIII . - ass TWIN PINES INVESTMENT LIMITED PARTNERSHIP FALCON ENERGY, INC. GENERAL PARTNER TWIN PINES COAL MINE WL PHONE 784-3361 .. P. O. BOX 112059 "ti"a•=~:rn~•~i; ... CANON CITY, COLORADO 81212 . _- .. _. = ., .. _' .. y February 12, 1986 Fig 2.7 1500 Mr. Gregg Squire Mined Land Reclamation Division 423 Centennial Building 1313 Sherman Street Denver, CO 80203 SUBJECT: TWIN PINES N0. 2 MINE, PERMIT N0. C-058-83 Dear Mr. Squire: In accordance with Stipulation No. 1 and No. 2 of Subject Permit, the Water Monitoring Report for the Quarter ending January 15, 1986, is submitted herewith. Mining at Twin Pines has progressed as shown on the attached Mine Map. Minor seepage has been encountered in the three (3) main headings during the reporting period. The amount of seepage has been directly related to proximity of the Last Chance Mine and the strike of rolls in the formation, which appear to parellel Che ridge line overlaying the mine. Generally, it appears that the majority of the water is seeping from the sandstone underlaying the coal seam. Due to the character of the seepage, accurate sampling of the ground water is impossible. An estimate of the amount of cratei entering the Mine was made by measuring pump discharge, duration and frequency. At this time pumping is required appromimently three (3) times per week for water accumulated at the face of the entry. When tested the accumulated water was pumped at a rate of 60 GPM for 20 minutes. The water had accumulated for 48 hours before pumping commenced. This would indicate inflow into the Mine of 600 gallons per day or 0.42 GPM. Considering all water lost through absorption, evaporation, and other means, it is estimated that the total inflow would be less than 1 GPM. In all probability, the seepage for the most part results from water accum- ulated in the Last Chance Mine in the last 14 years. This water could be attributed to- surface water flowing down the mine entries or a minor source of ground water. No conclusive relationship can be found between the water level in monitoring well No. TP-W-1, the Caldirola Well and the seepage. Water samples collected from the pump discharge were tested with the following results: Temperature 42° F.; PH 7.8; Conductivity 1900 Micro omens/CM @ 6°C; Iron 1.3 mg/1. It is anticipated that when the accumulation of water in the Last Chance Mine has been depleted, seepage into Twin Pines slopes will be considerably reduced.