Though testing is incomplete, state officials say they're convinced a Nevada marina where an estimated 100,000 trout, bass and catfish died poses no danger to humans or animals.
Environmental and wildlife officials say there's been no sign of any contamination like the pollutants that leaked into the pit in the 1980s from a nearby petroleum tank farm.
Scientists say the massive fish kill at the Sparks Marina was caused by a dramatic drop in the water's oxygen content, which they say is not all that uncommon.
They believe it was triggered by a weeklong cold spurt in December when lows hovered near zero at the former gravel pit converted into a marina 15 years ago along Interstate 80 just east of Reno.
But some citizens are questioning officials' assurances the marina is safe.
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