What’s clearer than the smoke still belching out of California’s vintage earthmoving machines? The state’s “in use” air-quality rule is getting retooled. The Associated General Contractors of America and the California Air Resources Board have reached an agreement to postpone the off-road diesel rule until 2014. What happens next may very well depend on the upcoming elections.

New data from AGC-sponsored study led to revised off-road diesel deadline.
Photo: Tudor Van Hampton For ENR
New data from AGC-sponsored study led to revised off-road diesel deadline.

In a joint Oct. 7 announcement, Mary Nichols, CARB chairwoman, and Michael Kennedy, AGC’s general counsel, agreed to resolve technical details attached to a complex set of regulations affecting in-use or existing machines that CARB put into motion in 2007.

“Stretching out the timelines and reporting requirements will make the path to compliance a lot easier while the construction industry recovers from severe financial hardships,” says Nichols, who adds that the extra time also will allow the industry’s marketplace to “create a turnover” of its older, dirtier equipment.

The proposed changes will need approval from the CARB board at its next hearing on Dec. 16-17. The changes would lower annual requirements, based on a fleet’s average horsepower, by no more than 5% to 10% of the fleet’s emissions. Previously, the rule called for reductions from 28% to 30%. The revision would extend double credit for early retrofits and reduce peak-year costs by removing the rule’s 2013 “Balloon Year.” Fleets had to meet 180% of the requirements of other years. The changes also would increase a fleet’s low-use threshold to 150 hours from 100 annually.

The new rule would remove 2012 requirements for fleets in compliance in 2010—about two-thirds of large fleets—which benefits firms that were proactive. It also would provide simpler compliance options for the smallest fleets. Those with less than 500 horsepower can phase out EPA-rated Tier 0 and Tier 1 diesel engines beginning 2017, rather than deal with fleet averages, and achieve more nitrogen oxide (NOx) benefits in later years, lowering NOx targets from 2017 to 2022 and requiring more Tier 4-interim and Tier 4-final engines, which phase in nationally for most off-road diesel engines in 2011 through 2014.

Kennedy says the proposed changes are based on new and far-lower estimates of emissions from off-road diesels. The association developed the new estimates earlier this year from its own study by Sierra Research, and over the summer the board staff largely confirmed them. In CARB hearings over the past few months, board members expressed concerns about the viability of the board’s data. “The new estimates provided a common starting point for changes that everyone agreed the data should drive,” Kennedy says.

As to what’s next on the off-road diesel agenda, William E. Davis, executive director of the Southern California Contractors Association, says further federal EPA involvement will depend on who controls Congress after the midterm election next month.

Davis says the EPA could come out with new federal ozone and/or particulate matter standards that would impact many states’ emissions regulations. “But depending on who runs the House and Senate and to what degree, those rules may never get moving,” says Davis. In California, many of CARB’s future regulations will depend on Proposition 23 passing—which effectively would neuter the landmark climate-change rule, AB 32—whether a Republican or a Democrat sits in the governor’s office.