2009-09-25_PERMIT FILE - M2009076 (24)

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C] • Phelps Dodge: Environmental Case Studies Climax Molybdenum Biosolids Success Story Phelps Dodge Corp.'s Climax Molybdenum Co. mine, located at an attitude of 3,200 meters in the Colorado Rockies, has over 1,500 hectares of disturbance visible to residents and visitors from the local highway. The contrast is dramatic: scenic views punctuated by the disturbances of neary a century of mining. The average growing season is six to eight weeks, the average annual temperature is 1 degree Celsius, and annual snowfall is 6.8 meters. Over the past 25 years, the mine has developed considerable experience in developing plant growth covers in these harsh climatic conditions. In the late 1980s, biosolid disposal costs in the resort communities surrounding the Climax mine approached US$1,000 per dry ton, and all the local wastewater treatment facilities were exploring cost-saving alternatives to placing the biosolid waste in landfills. In recent times the resort communities have been coping with explosive growth and increased biosolid production. In addition, ski trail expansion and booming construction generated great quantities of wood residuals - well over 25 percent of the local county's waste stream. The need for a new solution to biosolid management in conjunction with the need to dispose of wood residuals made great economic and environmental sense for use of these waste products as a reclamation growth medium at the mine. In 1996, Climax established a pilot demonstration project that showed the use of biosolids for reclamation would decrease reclamation costs at the site by up to 65 percent. In 1998, an agreement was made with the local wastewater districts to offset their disposal costs and to develop the beneficial use of biosolids. The capital cost savings to the local communities has been in the millions of dollars. About 1,000 dry tons annually of biosolids are transported to the mine with about one third being used to blend on a 1-to-1 basis with wood waste for reclamation of the surface of the Robinson tailing facility as range or wildlife habitat. This surface to be reclaimed is first covered with between 0.3 meters and 0.5 meters of waste mine overburden followed by neutralization with lime. The biosolid and wood chip mixture is then applied to the surface followed by an even application of high attitude grass seed varieties. New areas to be reclaimed each year are limited only by the availability of biosolids. After five years the revegetation program has been an unqualified success as evidenced by the fact that the reclaimed portion of the Robinson tailing facility has become a popular grazing area for herds of elk. The Climax Molybdenum Co.'s biosolids program was the recipient of the EPA National Special Award for biosolids use in 2001. Climax also received an award for outstanding reclamation in 2003 from the Colorado Division of Minerals and Geology for the same program. The beneficial use of the Climax mine's water rights is another example of the sustainable nature of this mine property. Positioned atop three major Colorado river basins, the site receives 630 millimeters of annual precipitation, 75 percent in the form of snow. Climax is capable of providing water diversion and storage for delivery in periods of critical water need. During the drought in 2002, Climax Molybdenum Co. exercised its water rights to deliver water both to the Colorado River Water Conservation District and to the City of Aurora. The mine has a track record of proven water development projects, including the Clinton Reservoir and Eagle Park Reservoir. The latter freshwater reservoir was constructed from 1993 through 1997 by reclaiming a 1960s-era tailing impoundment located at the headwaters of the Eagle River. About 1.2 million cubic meters of tailing was completely removed from within an oxide tailing impoundment. A cooperative agreement with Eagle Valley water users allows for maintenance of in-stream flow levels during periods of high water withdrawal in the Eagle Valley for winter recreation. The reservoir water quality meets drinking water standards and supports a fishery. Climax received a reclamation award from the Colorado Mine Land Reclamation Board in 2000 for this innovative project. Page 1 of 1 Note by Venttum lRteszm-ceac, ltme.: The ayIDpn??4itar? at r as oTO.34-5 meters aTate tie overburden facmt ceurnUmdcan wii b U=-- Q God ha P at Cbe IfffctWE GoPe6 1rf p limgwundmzmtt. iP3e reffetr to Exhibit tC and li? ffeir a detafled expkmaffon tlat Me waste wO fah-d-n t y be sH&Uy faIllkdjine fanid not need raay P-ea dolt watb lye. http://www.phelpsdodge.comICommunity-EnvironmentlEnvironmentlEnvironment OverviewlEnvi... 3/9/2008