CALIFORNIA AIR RESOURCES BOARD
South Coast Air Quality Management District
McCandless Auditorium
9150 Flair Drive
El Monte, CA
November 17, 1988
9:00 a.m.
AGENDA
Page
88-14-1 Public Hearing to Consider the Adoption of 001
Regulations Limiting the Sulfur Content and the
Aromatic Hydrocarbon Content of Motor Vehicle
Diesel Fuel.
88-14-2 Examination of the Need for Carbon Tetrachloride 356
Control.
88-14-3 Air Toxics Monitoring in the State of California. 403
Research Proposals
ITEM #88-14-1
Public Hearing to Consider the Adoption of Regulations Limiting
the Sulfur Content and the Aromatic Hydrocarbon Content of Motor
Vehicle Diesel Fuel.
RECOMMENDATION
The staff recommends that the Board adopt the staff's proposals
to limit the sulfur and aromatic hydrocarbon content of motor
vehicle diesel fuel.
DISCUSSION
Emissions from the Use of Diesel Fuel
In California approximately 2 billion gallons per year of diesel
fuel are consumed in motor vehicles. The consumption of this
fuel results in emissions to the atmosphere of the following
pollutants expressed as a percentage of the statewide total of
those emissions from all sources: oxides of nitrogen-25 percent
(700 tons per day), sulfur dioxide-17 percent (100 tons per day),
and particulate matter-3 percent (100 tons per day).
Air Quality Needs
Virtually every area of the state experiences exceedances of the
state standard for PM10, and some of the state's air basin have
experienced exceedances of the state standard for sulfate. The
South Coast Air Basin violates the federal and state standards
for nitrogen dioxide. Many air basins exceed the federal ozone
standard and the more stringent state ozone standard. Emissions
from diesel vehicles contribute to the exceedances of these
standards. In addition, emissions from diesel fuel combustion
contribute to the formation of acid precipitation. The products
of combustion of diesel fuel have also been found to be
potentially mutagenic and contain some identified and suspected
carcinogens.
Legislative Requirements
Several bills have been enacted that will require control of
diesel fuel composition. As a result of SB 151 (Presley),
enacted in 1987, beginning in 1989 the South Coast Air Quality
Management District may, subject to the approval of the Air
Resources Board, adopt regulations for the composition of diesel
fuel manufactured for sale in the South Coast Air Quality
Management District. In 1988 three major bills addressed control
of diesel emissions: AB 4392 (Brown), SB 1997 (Presley), and the
California Clean Air Act (AB 2595 Sher), as did SCR 100. Among
the requirements of these bills are provisions that the Board
achieve specified reductions of oxides of nitrogen emissions from
motor vehicles, hold hearings on diesel fuel specifications, and
prepare a plan to reduce toxic compound emissions from motor
vehicles.
Proposed Limits
Based on studies of the emission reduction effects and the costs
of reducing the sulfur content and aromatic hydrocarbon content
of diesel fuel, the staff believes that specifications for these
fuel properties are warranted.
In selecting what limits to recommend for the sulfur content and
the aromatic hydrocarbon content of diesel fuel, we considered
potential emission reductions, technology, costs, and cost-effectiveness.
On this basis, we are proposing the extension, statewide, of the 0.05
weight percent sulfur content diesel fuel limit which is now in effect
in the South Coast Air Basin and Ventura County. This would apply to all
refiners. For the aromatic hydrocarbon content of diesel fuel, staff is
proposing a limit of 10 percent by volume for large refiners and 20 percent
by volume for small refiners. The higher limit for small
refiners is to address the disproportionate cost small refiners
would incur if they were required to comply with a 10 percent
limit.
Impacts of the Proposed Regulation
Implementation of the proposals would reduce the various air
pollutants emitted from diesel vehicles from 7 to 82 percent
depending on the pollutant. Implementation of the proposals
would also reduce the potential cancer risk associated with
diesel exhaust by 10 to 17 percent.
To meet the requirements of the proposals, large oil refiners
would need to invest about $550 million, and small refiners would
need to invest about $100 million. The annual cost would be
about $200 million per year for large refiners and $35 million
per year for small refiners. The unit cost for producing diesel
fuel that meets the proposed specifications would be about 11
cents per gallon if the total cost were passed on to consumers.
The cost to consumers is difficult to predict as cost of
production is only one consideration in setting retail prices.
The cost-effectiveness of the proposal, considering the reduction
of all pollutants, is about $2.6 per pound and $3.6 per pound of
pollutant reduced for large and small refiners, respectively,
assuming that small refiners would blend to meet the aromatics
proposed limit.
The cost-effectiveness of this measure is comparable to that of
other measures recently adopted for particulate matter, nitrogen
oxides and cancer-causing air pollutants. The difference is that
this measure requires a much larger initial investment by
industry. For example, the trap-based particulate standards for
light-duty diesel vehicles, now in effect have a cost-effectiveness of
greater than $10.00 per pound of pollutant
reduced. The South Coast Air Quality Management District's
recently adopted measure to control oxides of nitrogen emissions
from refinery boilers and heaters has a cost-effectiveness of
about $4.50 per pound of emissions reduced.
Concerns
Industry representatives have opposed reducing the aromatic
hydrocarbon content of diesel fuel. They contend that the
additional benefit gained from reducing the aromatic hydrocarbon
content of diesel fuel is slight, and that the cost of doing so
is out of proportion to the benefit gained.
Other than refiners, the major industry segments that would be
affected by the proposals are the trucking and agricultural
industries. If fuel prices increased 11 cents per gallon, for a
typical truck with fuel economy of 6 miles per gallon, the diesel
fuel price increase boosts operating costs by 1 to 2 cents per
mile. For large farm implements consuming 4 to 8 gallons per
hour, this represents an increased cost of $.40 to $1.00 per
hour. This is about 2% of the cost of owning and operating such
large farm implements.
Support for adoption of this measure is expected from local air
agencies, particularly the South Coast Air Quality Management
District; various public interest groups; from local elected
officials and from some legislators.