The radar site from Pittsburgh's National Weather Service office recorded a band of snow downwind from the Beaver Valley Nuclear Generating Station and the coal-fired Bruce Mansfield Generating Station.
The waste heat from Beaver Valley and steam from Bruce Mansfield condensed into clouds in the very cold and dry atmosphere. Those clouds then precipitated as a trace to an inch of snow for communities downwind of the station.
Photo from ClimateCentral.org. Original image from National Weather Service
While forming clouds from the steam given off by generating stations is fairly common, it is not common to see precipitation from these clouds so clearly on Doppler radar.
This snow is not a concern to public health, as fresh water is heated and run through turbines at coal and nuclear power plants. Beaver Valley and Bruce Mansfield are both situated on the Ohio River.