Pit Dewatering
The Kings Mountain Mine’s open pit began accumulating rainwater over the last several decades since prior mining operations ceased in the 1990s. To continue to conduct additional prefeasibility studies and ultimately resume mining operations, the accumulated water must be removed. We expect to dewater the pit over an 18-month period. Albemarle is treating and discharging water under the limits of a state-issued National Pollution Discharge Elimination System (NPDES) permit which is required to protect downstream water resources.
Protecting the Wildlife
With concern for the pit lake inhabitants, wildlife biologists have
completed studies of the aquatic species to ensure that no threatened or
endangered species live in or around the pit. The only aquatic species
found in the pit is the common bluegill, which is not threatened or
endangered. Biologists anticipate that birds and mammals will adjust and
access other water bodies on and off-site.
The Dewatering Process
Treating the pit’s water requires a multi-step process to ensure the discharged water meets regulatory standards. To begin the process, water is conveyed by electrical pumps from the pit to a water treatment plant, where it is filtered to remove sediments and treated to remove any potential contaminants. Lastly, the water is treated by ultrafiltration to ensure clarity and transferred to a finished water tank before being pumped to discharge into Kings Creek.
Water quality is continuously monitored with in-process sensors for pH, clarity, dissolved oxygen, and temperature. We expect to conduct weekly to quarterly sampling along various points of the dewatering system from the treatment plant to Kings Creek.
Albemarle is discharging the water at a rate that is compliant with standards to preserve the integrity of Kings Creek and the river basin.
Managing Odors
There may be an occasional odor as the water level drops in the pit
during dewatering and decomposed materials at the bottom of the pit are
exposed. The water treatment process was specifically selected for pit
dewatering to mitigate odor during the process due to low dissolved
oxygen at depth in the pit lake. We anticipate there will be little to
no discernible smell beyond the pit during the process.
