Overestimate fueled state's landmark diesel law
Wyatt Buchanan, Chronicle Sacramento Bureau
Friday, October 8, 2010
California grossly miscalculated pollution levels in a scientific analysis used to toughen the state's clean-air standards, and scientists have spent the past several months revising data and planning a significant weakening of the landmark regulation, The Chronicle has found.
The pollution estimate in question was too high - by 340 percent, according to the California Air Resources Board, the state agency charged with researching and adopting air quality standards. The estimate was a key part in the creation of a regulation adopted by the Air Resources Board in 2007, a rule that forces businesses to cut diesel emissions by replacing or making costly upgrades to heavy-duty, diesel-fueled off-road vehicles used in construction and other industries.