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March 27, 2012 C- 1981 - 014 /Southfield Mine JHB <br />The inspection then progressed north of Fremont County Road to Drill hole SF- 87 -07. Drill hole SF -87 -07 is a 4" <br />diameter PVC cased hole that is capped with an unlocked PVC cap. Dr. Corley measured the water level at 87' <br />below the surface elevation. The PVC casing extends approximately 3" from the ground surface. <br />Returning south to Fremont County Road 15, a 6" steel casing was encountered. This pipe is ringed by an old tire. <br />This hole is open with no cap, and Dr. Corley measured the depth to the bottom at 70 feet. The hole was dry. <br />Overlaying the Southfield workings map and the historic mine workings found that this borehole did not overlay <br />or intercept any old mine workings, and is not shown on Southfield's "Mine Area Surface and Groundwater <br />Hydrology Map (Map 12). <br />Drill hole SF -87 -09 was visited. This drill hole is unsealed. It is cased with a 4" dia. PVC casing and is capped <br />with an unlocked steel cap. Drill hole SF -87 -09 is located close to the Section 24 /Section 25 boundary and is <br />north of the burn area. Dr. Corley measured the water level at SF -87 -09 at 211" below the PVC casing. <br />The inspection continued upstream to Surface water sampling point NC2. NC2 is the upstream Newlin Creek <br />surface water sampling point. Newlin Creek was flowing at this point. The stream channel was approximately 5 <br />feet wide with approximately 4" deep flow. There is no man -made flume or other defined structure that the creek <br />flows through at this point. George Patterson said that he measures the stream cross section and flow when he <br />takes the Surface flow measurement at this point. Daryl Mergen walked down the stream channel to determine <br />where the flow disappears prior to the Thompson Ranch Culvert. <br />An 8" steel pipe discharges water into Newlin Creek from the north at the sampling point. There was no surface <br />expression of this pipe on the north side of Fremont County Road No. 15. <br />The Newlin Creek stream channel is rocky and gravelly in this reach as well. the flow continues to the north east <br />for a while gradually diminishing and pooling several hundred yards upstream of the Thompson Ranch Culvert. <br />This reach is rocky and gravelly. and corresponds with the location of backfilled historic surface mine pit <br />conducted by GEC (Map 12). No surface expression of subsidence; cracking or holes, were noted in this area. <br />Jack Robeda sent a photo to the Division on 3/28/2012 showing that the surface flow in Newlin Creek had reached <br />the Thompson culvert on 3/28/2012. <br />Downstream monitoring surface water sampling point on Newlin Creek was dry. There is no man made structure <br />at this location. The channel is narrow, approximately 3 foot wide bottom, 2.5 foot high banks, with a top channel <br />width of 6 feet wide. There is a large boulder adjacent to the monitoring point that acts as a landmark. <br />Dr. Corley expressed his concerns that 1) the surface flow of Newlin Creek is draining into the underground mine <br />void via subsidence cracks. Dr. Corley's mine workings maps show the edges of pillared workings to correlate to <br />areas of known subsidence features. The location that Mr. Robeda observed Newlin Creek flow diminish in 2011 <br />correlated with the edge of a panel. 2) Dr. Corley questions the accuracy of Groundwater monitoring well MW- <br />NW. Dr. Corley believes a different drill hole; SF- 87 -07, may better measure the conditions in the mine than the <br />approved MW -NW well. 3) Dr. Corley believes the mine water pool has reached equilibrium already. <br />Number of Partial Inspection this Fiscal Year: 6 <br />Number of Complete Inspections this Fiscal Year: 3 <br />Page 3 of 6 <br />