'Gross Miscalculation' of Diesel Emissions Sets Back Calif. Law

'Gross Miscalculation' of Diesel Emissions Sets Back Calif. Law

The San Francisco Chronicle today has a big story about an even bigger cock-up from the California Air Resources Board: Apparently, through what reporter Wyatt Buchanan calls "grossly miscalculated" figures on diesel pollution, the CARB may be setting back not just the rule in question -- dealing with reductions in nitrous oxide and particulate matter -- but also raising questions about the Board's competence at a critical time.

Buchanan writes:

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.

The staff of the powerful and widely respected Air Resources Board said the overestimate is largely due to the board calculating emissions before the economy slumped, which halted the use of many of the 150,000 diesel-exhaust-spewing vehicles in California. Independent researchers, however, found huge overestimates in the air board's work on diesel emissions and attributed the flawed work to a faulty method of calculation -- not the economic downturn.

The scale of the miscalculation raises justifiable questions about how CARB came up with its numbers for the diesel pollution. But coming in the wake of another highly publicized miscalculation -- one that in 2009 saw the Board doubling the number of deaths attributable to diesel pollution -- the latest news could spell trouble for climate laws at the state and national level.

Next month, California voters will decide on Proposition 23, an oil industry-promoted measure that would effectively repeal the state's pioneering emissions-reduction law, AB32. AB32 is due to take effect next year unless Prop 23 passes, and questions about the science behind California's air and carbon dioxide emissions could provide ammunition to Prop 23's supporters.

More from Buchanan:

The setbacks in the air board's research -- and the proposed softening of a landmark regulation -- raise questions about the performance of the agency as it is in the midst of implementing the Global Warming Solutions Act of 2006 -- or AB32 as it is commonly called, one of the state's and the nation's most ambitious environmental policies to date.

AB32, which aims to reduce carbon emissions to 1990 levels by the year 2020, has come under intense political attack this year as the state prepares to elect a new governor. Critics cast the law as a jobs killer because of the expenses to industry and businesses in conforming to new pollution regulations. Supporters say it will reinvigorate the state's economy and create thousands of new jobs in the emerging green sector.

Buchanan's extensive report is all worth a read. Check it out here: "Overestimate fueled state's landmark diesel law."

Photo courtesy of the EPA via Wikimedia.