Engineering & Mining Journal

SEP 2012

Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr

Issue link: https://emj.epubxp.com/i/82657

Contents of this Issue

Navigation

Page 39 of 179

REGIONAL NEWS - EUROPE Dalradian Reports Positive PEA for Curraghinalt Project Dalradian Resources reported in late July 2012 positive results from a preliminary economic assessment (PEA) for a proposed underground mine at its wholly-owned Curraghinalt gold deposit in County Tyrone, Northern Ireland. The study outlines a 15- year mine life at a processing rate of 1,700 mt/d, producing approximately 145,000 oz/y of gold. Average mined grade is esti- mated at 8.1 g/mt gold. Life-of-mine gold production is estimated at 2.223 million oz. Capital expenditures to the start of pro- duction at Curraghinalt are estimated at $192 million, including contingencies of $36.9 million. Sustaining capital is esti- mated at $110 million, for a total life-of- mine capital spend of $302 million. Cash operating costs are estimated at $532/oz of gold produced. Micon International led the Curraghinalt Exploration activity at Dalradian Resources' Curra- ghinalt gold property in Northern Ireland. (Photo cour- tesy of Dalradian Resources) REGIONAL NEWS - ASIA Oyu Tolgoi Phase-one Construction Nearing Completion Turquoise Hill Resources, formerly Ivanhoe Mines, reported in mid-August 2012 that overall construction of the first phase of devel- opment of the Oyu Tolgoi copper-gold-silver project in the South Gobi region of Mongolia reached 90% completion at the end of the second quarter of 2012 and had advanced to 94% completion by the end of July. Total cap- ital invested in first-phase construction to the end of second quarter was approximately $5.2 billion. Turquoise Hill holds a 66% interest in the project. The government of Mongolia holds the remaining 34%. Phase-one Oyu Tolgoi mine production will be from the Southern Oyu open-pit. A concentrator, with related facilities and necessary infrastructure to support an ini- tial throughput of 100,000 mt/d, is being constructed to process the ore. Initial pro- duction of copper-gold-silver concentrate is 38 E&MJ; • SEPTEMBER 2012 expected in the second half of 2012, and commercial production is expected to begin in the first half of 2013. Pre-stripping of overburden to gain access to ore in the open-pit was complet- ed during the second quarter. Pre-commis- sioning of the primary crusher, overland conveyor, and coarse-ore stockpile circuits was progressing on schedule, with the first ore delivered to the crusher in July 2012. Construction of the concentrator was 95% complete at the end of the second quarter and ahead of schedule. Line No. 1 of the concentrator was on track to be com- pleted and pre-commissioned in the third quarter; Line No. 2 was on track to be com- pleted and pre-commissioned in the fourth quarter. Commissioning of the concentrator with ore will depend on the availability of electrical power from China and successful completion of final mechanical components. Underground lateral development at the Hugo North Deposit at Oyu Tolgoi was suspended in February 2012 as planned to enable the upgrading of hoisting equip- ment at Shaft No. 1. Underground lateral development was scheduled to resume in September. Construction of Shaft No. 2 at the Hugo North Deposit was progressing well, and the headframe had reached its final height of 96 m. The headframe and ancillary buildings were 95% complete at the end of the second quarter and ahead of schedule. The shaft had reached a depth of approximately 460 m below surface. Long-term sales contracts have been signed for 75% of the Oyu Tolgoi project's concentrate production for the first three years. Including renewals, 50% of concen- trate production is contracted for 10 years. www.e-mj.com PEA study. The mine plan developed by Micon is based on mechanized longhole mining, with ramp access and truck haulage. Ramp access was chosen over shaft access due to the long lateral extent and relatively shallow depths of the deposit. The deposit is open at depth, and a shaft may be required in the future to access levels below the current mine plan. The mine plan is inclusive of inferred resources, which will require further explo- ration drilling to upgrade them to higher resource categories. The proposed Curraghinalt processing plant has a conventional flowsheet of crush- ing, grinding, cyanidation and conventional tailings disposal. Total gold recoveries, based on existing metallurgical test work, are expected to be approximately 92%. Dalradian Resources is a Canadian jun- ior company based in Toronto. "Our next steps are to better understand the existing Curraghinalt resource; prove, through drilling, that the system has a lot of room to grow; and move ahead with planning and permitting for underground develop- ment. We have people and drills on the ground right now working toward these goals," Dalradian Chairman and CEO Patrick F.N. Anderson said.

Articles in this issue

Links on this page

Archives of this issue

view archives of Engineering & Mining Journal - SEP 2012