Laserfiche WebLink
During Site Visit 2, MGC recommended that BMRI uncover the outlet area to expose the pipe <br />outfalls and to try to alleviate the seepage emerging from the embankment. On Initial Site <br />Inspection in May 2013, this work had been completed and three closely spaced pipes were <br />visible (Figure 9). The middle pipe appeared to be at least partially clogged and seepage was <br />still emerging from the embankment slope above the pipes. All three pipes appeared to be <br />flowing. The facility supervisor, Julio Madrid, reported in January and February, 2014 that <br />monitored flow rates from the sub -drain system have remained unchanged since before and after <br />the pipes were uncovered, and that the seepage persists on the embankment slope above the <br />pipes. From the San Luis Project As -Built Plans (SRK, 1991) it is estimated that the grade on <br />these pipes is approximately 2 percent. The highest observed seepage above the pipe outlets <br />during Site Visits 2 and 3 was estimated at 5 feet above the pipes, which would indicate that <br />water could be backed up in the pipes a minimum of 250 feet. Recommendations for cleaning <br />and inspecting these drain pipes are provided in Section 6.2. <br />Figure 9 Initial Site Inspection, Outlet After Uncovering, <br />Looking Upstream from Just Below Outlet <br />San Luis Project Miller Geotechnical Consultants <br />Tailing Dam Data Report 15 February 2014 <br />