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Page 3 <br />Sump Area <br />May 5, 2009 <br />The sump had recently been pumped and water from the drainage system was flowing into the bottom <br />of the sump retention area. This flow was estimated at 2 to 3 gallons per minute (gpm). It could not <br />feasibly be measured due to the geometry of the sump's surface. An inspection of the sump stub drift <br />indicated that seepage that was observed during the June visit is still present, perhaps of smaller <br />quantities. Seepage occurs at numerous locations on the back on ribs at rock bolts and various apparent <br />fractures underneath the shot-creted walls. An estimated combined rate of seepage in this drift that is <br />contributing water to the sump floor was less than or equal to 1 gpm. (Photograph 1, Attachment A). <br />Drift 10000 at Turnaround <br />Pooled water was observed at this location as a result of leakage from a borehole on the back of the <br />tunnel. The floor was saturated mud. Seepage was common on the ribs of the tunnel also (Photograph <br />2, Attachment A). Although much of the rock in this area appeared wet, some of this water could have <br />been due to condensation of water on the rock surfaces from the ventilation system air. Field <br />parameters were measured at this location (see Table 1). <br />Drift 11000 at Face <br />A large pool was present here, approximately 40 ft long and as wide as the tunnel. Depth was <br />approximately 6 inches, with a maximum depth of approximately 8 inches. A good portion of the <br />exposed formation in the drifts is Salt Wash sandstone, or a related channel sandstone unit. <br />Most of the water at this location appeared to have accumulated as a result of seepage from the face of <br />the workings (Photograph 3, Attachment A). However, some seepage was evident from the back and <br />walls (ribs). The nature of the seepage did not allow for measurement, as water emanates primarily <br />from fractures and coats rock surfaces with a thin film of water. No channelized flow in rills was <br />observed. It was estimated that the cumulative flow rate emanating from formation in this area was less <br />than 1 gpm. <br />Common to underground workings, flow of this diffuse nature is difficult to quantify. If necessary for <br />mine water management, collection systems similar to that which was built in the decline can be <br />constructed. Such systems may allow for quantification of formation yield. The sources of groundwater <br />entering the mine include (1) conduit flow in boreholes that penetrate overlying water-bearing strata, <br />(2) flow from storage of groundwater in the surrounding rocks during the time that the decline was <br />flooded, and (3) ambient groundwater in the strata surrounding the workings. On the basis of other data <br />that has been provided by EFR, the latter component of flow is expected to be small from the Salt <br />Wash Member. <br />The field parameter data collected in the mine workings during the inspection indicate relatively <br />uniform conditions (Table 1). The pH of 9.0 for the sump reflects the high pH measure in June (10.3) as <br />a possible result of the recent application of shot-crete in this stub drift just prior to the June 2008 <br />reconnaissance. The dissolved oxygen (DO) and oxidation-reduction potential (ORP) values indicate <br />slightly oxygen-deprived and possibly less-oxidating conditions, as to be expected in a groundwater <br />environment. <br />Surface Reconnaissance <br />In accordance with recommendations stated in the September 2008 report, WWL focused on <br />surface reconnaissance in Lumsden Canyon below the Whirlwind mine site. This reconnaissance <br />Weans032709.doc