Summary	of	Interagency	Working	Comments	on	Draft	Language	under									

E.O.	13563	and	12866	Interagency	Review.		Subject	to	Further	Policy	Review.

Comments on U.S. Environmental Protection Agency Proposed Rule, “Control of Air Pollution from 

Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards,” RIN 2060-AQ86

As EPA granted the waiver for California’s program in December 2012, the costs and benefits for that 

program should be included in the baseline of the RIA analysis for Tier 3. California’s air pollutant 

standards have long been different than other parts of the country so it makes both analytic and policy 

sense to consider the incremental impacts, costs and benefits of the rule with and without the California 

program. It is requested that EPA breakdown and present these incremental impacts for the scenarios 

laid out in the matrix below. 

A clarifying question would be whether the seven other states that adopted California’s standard would 

also be included in the baseline for Tier 3. Presumably they should be included in the baseline if they 

adopted California’s program; however, would the seven other states be preempted by the federal 

program if Tier 3 goes into effect? 

Fuel Sulfur Only Fuel Sulfur and Vehicle Controls

Tier 3 (not counting CA) A B

Tier 3 (entire country) C D

A – This breakout will incorporate the impacts of the California program in the Tier 3 baseline so it 

separates the costs and benefits of the California program from the Tier 3 program. The costs and 

benefits of the Tier 3 program will be estimated for all states outside of California and just for the fuel 

sulfur portion of Tier 3, not the vehicle controls portion of Tier 3. 

B - This breakout will incorporate the impacts of the California program in the Tier 3 baseline so it 

separates the costs and benefits of the California program from the Tier 3 program. The costs and 

benefits of the Tier 3 program will be estimated for all states outside of California covering both the fuel 

sulfur and vehicle controls portions of Tier 3. 

C – This breakout will incorporate the impacts of the California program in the Tier 3 cost and benefit 

analysis, although would only apply to the fuel sulfur portion of Tier 3 and not the vehicle controls 

portion of the program. 

D - This breakout will incorporate the impacts of the California program in the Tier 3 cost and benefit 

analysis and is what the agency has provide to date. 

EPA Response

The Tier 3 proposal does not include California’s Low Emission Vehicle III (LEV III) program in the 

baseline because the Tier 3 proposal’s analysis was initiated and completed well before EPA granted the 

waiver for the California LEV III program in December 2012. However, for the final rule’s analysis we will 

include LEV III in the baseline for California and the other states that have adopted it. 
Summary	of	Interagency	Working	Comments	on	Draft	Language	under									

E.O.	13563	and	12866	Interagency	Review.		Subject	to	Further	Policy	Review.

EPA Response (continued)

With respect to the requested matrix, it is not possible to break out benefits in this manner. The 

Tier 3 program is a joint vehicle and fuel program that is designed to maximize environmental benefits. 

Our analysis modeled the air quality impacts of this total program; the health effects and monetized 

benefits are estimated from this air quality modeling of the total program. As a result, it is not possible 

to identify the air quality impacts, health effects, or benefits of a fuel sulfur program that would be 

independent of a vehicle program. Similarly, as the air quality modeling accounts for cross-state 

transport of pollution, it is not possible from the proposal’s analysis to separate the impacts of Tier 3 in 

California from the total program benefits. As mentioned above, we will be conducting new air quality 

modeling for the final rule that will not include emission reductions from Tier 3 vehicles and fuels in 

California.