State scientists in Alaska found more than 100 dead fish in Sherman Creek, downstream from the Kensington Mine, in August. Seven months later, Coeur Mining, the mine’s operator, and state authorities have not determined why the fish died off.
Lab testing on creek samples and mine effluent showed no evidence of pollution, according to a November letter from Coeur Mining. However, watershed ecologist Chris Sergeant hypothesized that contamination might have entered the creek prior to testing.
The sergeant emphasized the crucial need to regularly sample the water near mining operations. On August 8, mine workers used RocKracker, an explosive linked to toxicity in marine environments near Sherman Creek…