Sid....the USGS study on save the salt site "documents" says
around 55,000,000 tons salt removed just from 1960 to 1988
if say 15 lbs lost per vehicle...1960's and 70's likely less than 800 vehicles
who knows...if it was 800 vehicles at 15 lbs each, equals 12,000 lbs , so 6 tons per year over 28 yrs equals 168 tons vs 55,000,000 lost over same time per the usgs study......as simple example.....not meant to be exact potrayal of reality...!!!!
0.0003 % so about 3 ten thousandth of one percent....
but hey....its a positive contribution...right...?
a bit like a prius....
perceptions are important
disclaimer...
praise to "save the salt" busting their arses to help save Bonneville...