2007-12-19_REVISION - M1988112 (12)

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The following design conditions were developed to guide the irrigation pipeline design process: Define a pipeline alignment between the West Pit and the ranch. The alignment will: (1) be located entirely on property either owned by BMRI or Newmont Realty, or where BMRI has an existing pipeline installation and holds an existing easement, (2) does not interfere with major site facilities, and (3) minimize pipeline length while avoiding excessive earthworks for pipeline construction. • Pipeline construction will use either the existing steel pipeline installation or will replace the existing pipe with HDPE pipe having the capacity to convey the maximum required irrigation flow. • The pipeline profile will allow for gravity flow to the extent practicable without requiring extensive earthwork for excavation. • The pressure rating of the pipe shall be sufficient to withstand the maximum anticipated pressure in the pipe. • Air Vacuum Air Release valves (AVAR) will be located along the pipeline high points where air pockets may tend to accumulate or a maximum vaccum may develop (i.e., high points in the pipeline where flow will change from full flow to partial flow conditions). • Blowoff risers and isolation valves shall be located along the pipeline at low points in the pipeline to allow for full drainage of the pipe and at other locations where isolation is required for operations and pressure testing. When drainage of the pipeline becomes necessary for maintenance or repair, it will be accomplished by first draining the line by gravity flow at these blowoff points, and pumping the remaining water from the line to the extent possible. Water drained from the pipeline will be transferred to a water truck and transported to the West Pit irrigation ponds. • Provide for the ability to perform pressurized leak testing of sections of the completed pipeline prior to placing the pipeline in service. The pressure used in the leak test shall be at least 125 percent of the normal operating pressure but shall not exceed the pressure rating of the pipeline, valves, fittings, and other piping components. • The pond and pipeline designs shall maintain the ability to transfer water to the TDA via the existing tailings water supply pipeline as a contingency during startup and shakedown of the new water management system. A hydraulic analysis was performed to ensure that the pipeline alignment, sizing, and pressure rating would be appropriate at the design flow. The analysis was performed Battle Mountain Resources, Inc. 30 P:\Pmjects\212-Ncw nt(SenLws)VS=L. \Pamit Ameodmem - West Pit Meregem AV5 Report & PDFs\Tezt\Pe tAmendment_v5adoc December 2007