Laserfiche WebLink
3 <br /> Construction began on interceptor canals surrounding the tailing facilities. The purpose was to intercept <br /> fresh water and divert it around the tailing area, discharging it downstream preventing its contact with <br /> process water. <br /> Oxide Tailing Pond <br /> Virtually all mining operations are complex, and Climax is no exception. It has always been a mine <br /> in transition, but the focus of this paper is on the three extremely dynamic decades of mid-1960's to early- <br /> 1990's. Beginning in the 1960's, we must discuss a process change that in and of itself is rather <br /> insignificant, but will prove to be of great interest in the implementation of compliance strategies regarding <br /> the Clean Water Act. In the 1960's research was begun on an economical method of recovering <br /> molybdenum from the oxide cap over the sulfide ore body. This resulted in an hydrometallurgical process <br /> to reclaim molybdenum. A plant was constructed and operations began in 1965 only to cease in 1968 due <br /> to poor economics. A separate pond had been built for the oxide tailing due to its high sulfuric acid <br /> content which had an inhibitive effect on the sulfide flotation circuit. The designers of the oxide recovery <br /> circuit performed calculations suggesting the oxide tailing liquors would eventually evaporate. <br /> By 1970 it was apparent the oxide tails would not dry by evaporation. Research was begun and a <br /> neutralization plant was in operation by 1973. Using limestone, it was successful from the standpoint of <br /> pH neutralization. However, when the neutralized water was placed in the sulfide process water system, a <br /> significant drop in mill recovery resulted. It appears the presence of ferric and ferrous sulfates were <br /> interfering with flotation. The solution was to bleed the neutralized water into the system at a rate slow <br /> enough to prevent recovery problems. It should be noted that the addition of ferric sulfate is one of the <br /> methods of removing molybdenum from water. This point becomes important later. <br /> Exoansion of Sulfide Tailinsa Ponds <br /> By the mid-1960's, it was evident that the tailing capacity must be expanded, and design of a new <br />