REP22737 - Laserfiche WebLink

Home Browse Search

I Annual Hydrology Report April 28, 1988 Page 16 Panel 1W3S De•;alopment mining in panel 1W3S began in March, 1987. At the end of water year 1987, Panel 1W3S was developed to approximately 24 crosscut. Wet/damp roof areas were encountered from approximately 11 crosscut to 24 crosscut. These wet areas produced no measureable inflows but were fairly extensive over a wide area. This water is thought to be a general trend in this area associated with sandstone channels directly above the coal seam and with Lone Pine Gulch features. Exhibit II shwas the wet areas. 1W35 panel may encounter some additional wet areas, but they should be minimal as the development proceeds south out of the Irene Pine Gulch I influence. Once retreat mining occurs, sane additional water may be encountered as subsidence affects the strata directly above the coal. If flow is encountered is it likely it will be on the order of that encountered in 1W2S panel. Panel 1W4S Development mining was begun in panel 1W4S in October, 1987. Exhibit II shows wet and damp areas in this panel as well as mining up to the date of writing of this report. As in adjacent panel 1W3S, 1W4S is exhibiting the l general trend associated with the sandstone channels and associated Irene J Pine Gulch features. It is anticipated that panel 1W4S will encounter additional wet and/or damp areas as it is advanced beneath Lone Pine Gulch. Water encountered should be in the form of roof drips, wet ribs, and damp floor. It is not expected that any siynificant flows will be encountered in development during 1988. 1st East Submain Development mining in the 1st East Submain from 13 crosscut to 16 crosscut was done in 1987. Water was encountered in the 1st East Submain and is thought to be associated with Sylvester Gulch features in the area. A sump was driven to the North between crosscuts 14 and 15 to collect water. No ' flows were measurable but they ace estimated to be 2 to 3 gallons per minute. A pipe will be installed from the sump to connect with the pipe which pumps out portal No. Z and into ~~ID-I. ' Development mining which advances the 1st East Submain will likely encounter additional water in the topographic transition and under low Dover beneath Sylvester Gulch. If necessary, this water will be pumped out ' Portal No. 2. It is thought that, although the area is wet, no significantly large flows will be encountered. ' Samples to date indicate water quality in the mine to be good and should pose no problem for discharge. The ultimate discharges should readily meet NPDES effluent limitations after settling and there should be no measureable impact to 7 receiving waters. Quality of water discharged should be similar to 1987 as shown in Tables 1.4-1, 1.4-2, and 1.4-4.