2012-04-19_REPORT - M1977004 (2)

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Piezometer Location Material Diameter (ID- Inches) Depth (ft BGS) Screen Length (ft) Screen Interval (ft BGS) Static Water 09/16/2011 (ft bgs) IC- 10300R Sch. 80 PVC 5 208.95 20 188 - 208 188.12 IC- 10370R Sch. 80 PVC 5 207.87 10 197 - 207 197.83 Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2011 Annual Reclamation Report rule 16 "Standards for Plugging and Sealing Wells and Boreholes ". Piezometer construction details are is presented on the table below. New Piezometer Construction Details Notes: m = meters ID- Inches = Interior Diameter in inches ft BGS = Feet Below Ground Surface ft = feet The new piezometers consist of a 5 -inch interior diameter (id) schedule 80 Polyvinyl Chloride (PVC) riser and screen and completed with an 8 inch interior diameter steel stick up and well cover with a 3 ft. by 3 ft. concrete well apron secures the stick -up pipe. Water level measurements were first taken from the new piezometers on September 9, 2011. More detailed discussions and figures are presented in the 2011 Annual Geotechnical Report filed with the Division in December 2011 and in the Piezometer Replacement Field Report filed with the Division in October 2011. 4.6 Water Quality Monitoring As outlined in TR4, Homestake has monitored water quality since 1994 to verify the intended effectiveness of installation of the Pinnacle Adit plug. Water quality monitoring was conducted in 2011 including sampling points located at the North Pit Lake discharge (Sample Point NPL), the Tie Camp Creek drainage (Sample Points TCCDRN and TCC), the site discharge POC (Sample Point SW -33), as well as spring and seep surveys performed in the spring and fall. Monthly discharge- monitoring reports (DMRs), pursuant to Colorado Discharge Permit System (CDPS) number CO- 0022756, were submitted to the Colorado Department of Public Health and Environment (CDPHE) for 2011. Monitoring for the CDPS was conducted at the designated POC SW -33, shown on Figure 3. Analytical tests conducted for the DMRs at SW -33 as required by the CDPS include: flow; dissolved radium 226; total radium 226/228; total uranium; pH; total suspended solids (TSS); total dissolved solids; oil and grease (visual only); potentially dissolved zinc; and whole effluent toxicity (WET). During 2011, all analytical results were below the CDPS permit's 30 -day average or daily maximum limitations and WET testing results were within permit limits. The 2011 DMRs are on file with the CDPHE -Water Quality Control Division. Water quality monitoring will continue in 2012 4.7 Radioactive Materials License The RTP building, foundation and sediments excavated from the upper portion of Indian Creek below the old RTP area were placed in the Tie Camp Disposal Cell in 2001. Final grading and revegetation of the RTP area was started in 2002 and completed in 2003. With the removal of the RTP, the radioactive source material and any treatment capacity have been removed. Small concentrations of the Radium 226 isotope remain in the sediment deposited upstream of the sediment control embankment. The Radioactive Materials License (RML) for the Pitch Reclamation Project was renewed in April 2008. License renewal #14 allows Homestake to manage the Tie Camp Low -Grade Stockpile and the sediment upstream of the sediment control embankment within the guidelines of the license. A copy of the 2011 Annual RML letter report is provided in electronic Adobe Acrobat Portable Document Format on the CD attached to this report. Pitch 2011 Reclamation Finalreport 19Apr12.Doc 17