Laserfiche WebLink
e XOM AECOM 303-694 2770 tel <br /> /'7� 6200 S Quebec St 303 694 3946 fax <br /> Greenwood Village,CO 80111 <br /> www.aecom.com <br /> September 14, 2017 <br /> Mr. Raymond Lazuk <br /> Environmental Manager <br /> Climax Molybdenum Company- Climax Mine <br /> Highway 91 — Fremont Pass <br /> Climax, CO 80429 <br /> Subject: Mayflower(5 Dam) Seepwater Return Pipeline Leak, Mayflower Tailings Storage <br /> Facilities, Climax Mine, Permit No. M-1977-493 <br /> Dear Mr. Lazuk: <br /> AECOM serves as the Engineer of Record (EOR)for Mayflower Tailings Storage Facilitates (TSF)at <br /> the Climax Mine, near Fremont pass Colorado. In this capacity AECOM was recently requested by <br /> Climax Molybdenum Company to review the Mayflower Seepwater pipeline leak and evaluate any <br /> present and potential future dam safety impacts on 5 Dam stability. <br /> The Mayflower Seepwater pipeline pumps seepwater from the toe of 5 Dam up to the seepwater <br /> pond and pumpstation near the toe of 3 Dam (Tenmile). This 14-inch HDPE pipeline is located <br /> outside of the structural shell of the dam. The leak was first observed on September 5, 2017 and is <br /> shown in the photo below taken during AECOM's site visit on September 7, 2017. The leak is located <br /> near the edge of the existing Mayflower pond, over 2,000 feet upstream from the current dam crest <br /> and approximately 200 feet from the shoreline with a visible surface feature of approximately 10 feet <br /> in diameter. The leak is believed to be a result of a faulty valve buried approximately 12 to 15 feet <br /> below the tailings surface in this area. <br /> Photo 1- Seepwater Pipeline Leak Location (shown with arrow) near Mayflower Decant Pond <br /> M:\DCS\PROJECTS\WTR\60538541_CLX_GEN17\300-COMMUNICATIONS\310-CLIENT\MAYFLOWER SEEPWATER RETURN 09-14-17.DOCX <br />