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Show (ORE HAULAGE TUNNEL WORK PROGERSSING Crews of the Utah Construction Company have drilled a total of 16,592 feet on Kennecott Copper' new 1 8,000 foot ore haulage tun- 1 nil. : The $11,000,000 project was j started in November of 1956 and will probably be completed in the spring of next year considerably ahead of schedule. The tunnel will : connect the bottom of the deepen- ing open pit copper mine with the Copperton Assembly Yards at the mouth of Bingham Canyon. The project is part of Kenne-cott's Kenne-cott's continuing effort to improve operations, effect better methods and thus remain strong in today' highly competitive copper market. Although progress on the new 5490 tunnel has been slow during the past few weeks, officials say it will probably still be completed ahead of the initial completion date of early I960. F'reviously working in fractured porphyry rock, crews of the Utah Construction Company report they are now back in quartzite formation forma-tion and progress has improved. Quartzite is harder than porphyry rock, holds well and does not require re-quire the extensive reinforcement needed in porphyry areas. I he present slow progress is in contrast to the record pace crew maintained from September 1, 1957, to April I. 1958. Crews set a new world's record for drilling in March of this year. Workmen drilled 1,363 linear feet of tunnel in 26 working days. During the record-setting month, 350,000 cubic cu-bic yards of rock were removed from the tunnel. At points, the concrete lined tunnel will be 1,800 feet beneath the top "lip" of the open-pit mine. The tunnel will be 18 feet wide and 24 feet high and will accomodate a single standard gause. track. Centralized traffic control will be used to coordinate movement of ore and waste trains in and out of the tunnel. At the present time, the mine is served by two other tunnels progressively pro-gressively being shortened as the mine expands in size. They are the 6040-foot level tunnel, finished finish-ed in 1945 and the 5840-foot level tunnel finished in 1953. Principal objective of the new tunnel is to reduce mining cost through elimination of the uphill haul by trains coming from the bottom of the deepening pit. The project is an example of the constant con-stant struggle in mine economic where expenditures must be made from earnings in order to reduce costs at properties where the ore grade is gradually declining. |