State of California
AIR RESOURCES BOARD

Pacific Room
Holiday Inn
Fisherman's Wharf
1300 Columbus Avenue
San Francisco, CA

August 24, 1978
10:00 a.m.
AMENDED
AGENDA Page

78-16-1 Approval of Minutes of July 27, 1978 Board Meeting

78-16-2 Public Hearing Regarding Proposed Extension of 001
Exemption of Diesel Vehicles from Certificate of Compliance
Requirements through 1982

78-16-3 Public Hearing for Reconsideration of Air Resources 012
Board Regulation Limiting the Sulfur Content of Unleaded
Gasoline Sold in California

78-16-4 Other Business -
a. Executive Session - Personnel and Litigation
b. Research Proposals
c. Request for Delegation of Authority to Make
Changes to 1979-80 Light-Duty Truck Standards
Applicable to Four-Wheel Drive Vehicles Below 4000
Pounds Inertia Weight

Public Hearing to Consider the Exemption of Diesel-Powered
Vehicles From Certificate of Compliance Requirements.

RECOMMENDATION

Adopt Resolution 78-44.

SUMMARY

The present exemption of heavy-duty diesel vehicles from
Certificate of Compliance requirements will expire on December
31, 1978 unless the Board takes action to extend it. In
addition, 1980 and later diesel passenger cars and 1978 and later
light-duty diesel trucks will be required to meet Certificate of
Compliance requirements unless the Board exempts them. The ARB
staff has found that, at the present time, the small size of the
diesel population would not provide sufficient economic
incentives to induce the mechanics or service stations to
participate in such a program. Moreover, at the present time, no
reliable short emissions test exists for diesels. Expensive
equipment would have to be purchased to perform loaded mode tests
and mechanics would have to be extensively trained. As a result,
a diesel C of C program would not be cost effective. The staff
therefore recommends that the Board exempt diesel vehicles from
Certificate of Compliance requirements through 1982. At that
time, the staff will investigate the feasibility of either
including diesels in the MVIP or of creating a separate
inspection and maintenance or anti-tampering program for them.

ITEM NO.: 78-16-3

Public Hearing for Reconsideration of Air Resources Board
Regulation Limiting the Sulfur Content of Unleaded Gasoline Sold
in California.

RECOMMENDATION

Adopt Resolution 78-45, thereby amending Section 2252 of Title 13
of the California Administrative Code. The amended Section 2252
would continue the existing schedule for reduction of the sulfur
content of unleaded gasolines (currently 400 parts per million,
and 300 ppm after January 1, 1980) sold at retail in the South
Coast Air Basin, in the Counties of Ventura, Santa Barbara, San
Luis Obispo, Kern, San Diego and Imperial, and in those portions
of the Counties of San Bernardino, Los Angeles and Riverside not
within the boundaries of the South Coast Air Basin. Section 2252
as amended would truncate the existing schedule at the current
sulfur content limit for unleaded gasoline (400 parts per
million) in all other areas of the state.

SUMMARY

On June 30, 1975, the Air Resources Board adopted Resolution 75-
33 effecting the following schedule of limitations on the sulfur
content of unleaded gasoline sold at retail in California.

Maximum Sulfur Content Effective Date of
(Parts per Million by Weight) Limitation

500 January 1, 1976
400 January 1, 1978
300 January 1, 1980

On November 30, 1977, the Western Oil and Gas Association
petitioned the Board to reconsider and to repeal Resolution 75-
33. The petition contends that the Board adopted the resolution
on insufficient grounds and in response to predictions by the
Environmental Protection Agency of dangerous levels of sulfuric
acid emissions from automobiles equipped with catalytic
converters. The sulfate levels predicted by EPA have not been
experienced.

During 1977, the California ambient air quality standard for
sulfates was violated in the South Coast Air Basin on an
estimated 91 days, and there were 20 sulfate episodes (i.e.,
oxidant level of .20 ppm or more concurrent with a sulfates
standard violation) during that year. The California ambient air
quality standard for sulfur dioxide was violated in the South
coast Air Basin on 13 days in 1977.

Analyses show that, in order for six key air monitoring stations
in the South Coast Air Basin (SCAB) to record compliance with the
24-hour state sulfate standard at all times, sulfur oxides
emissions which were experienced in 1973 would have to be reduced
by 74 percent. Analyses also show that, by 1990, sulfur dioxide
emissions from automobiles in the SCAB will be reduced to about
25.8 tons per day if the sulfur in gasoline regulation remains in
effect, whereas such emissions could reach about 86 tons per day
in the absence of the regulation. Additionally, direct emissions
of sulfuric acid or sulfates from catalysts would add
substantially to the ambient sulfate concentration.

From these analyses, it is concluded that no relaxation of the
scheduled sulfur content limit of 300 ppm for unleaded gasolines
should be allowed in the south Coast air Shed or in neighboring
counties where gasoline destined for consumption in that air shed
could be purchased.

Retention of the present regulation is needed in the San Diego
Air Basin to maintain the California air quality standard for
sulfate, since concentrations close to the standard have occurred
recently. Violation of the sulfate standard by a wide margin in
Kern County requires that SOx emissions be kept to a low level
there.

Sulfur oxide emissions-related air quality is considerably better
in the northern portion of the state than in the South Coast Air
Basin and the relative contribution of gasoline to total sulfur
oxides emissions is smaller. If high emissions of sulfate from
exhaust catalysts do not occur, acceptable air quality can be
achieved in most of the northern portion of California without
limiting the sulfur content of unleaded gasoline to 300 ppm. In
view of the potential impact of direct emissions of sulfuric acid
or other sulfates from exhaust catalysts, however, the sulfur
content of unleaded gasoline should not be allowed to rise above
400 ppm. In addition, truncation of the present regulation at
400 ppm in the San Francisco Bay Area Air Basin is advised only
if new controls are implemented there to reduce emissions of
sulfur oxides from industrial sources.

Limited data on the costs of retaining the regulation for
unleaded gasoline indicate incremental gasoline productions costs
of less than 1› per gallon even at 100% unleaded production at
three reporting refineries that do not now have the facilities to
reduce the sulfur content to the required amount. Other refiners
would probably incur a much lower cost. Energy costs would be
modest as would increased emissions of SOx, NOx, and particulate
matter from the desulfurization facilities. An alternative to
installing the desulfurization facilities at the three equipment-
needing refineries would be for them to limit their capacity to
produce unleaded gasoline. This alternative could also entail
increased production costs.

The foregoing cost estimates are from only the three refiners who
chose to submit material in support of the WOGA petition. It is
assumed that other WOGA members anticipate lesser costs.

Table of Contents

Page

I. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

II. Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
A. Events Prior to April 17, 1975 . . . . . . . . . . . . . . . . .4
B. Staff Report 75-8-6, April 17, 1975. . . . . . . . . . . . . . .6
C. Board Meeting of May 29, 1975. . . . . . . . . . . . . . . . . 12
D. Staff Report 75-13-2, June 30, 1975. . . . . . . . . . . . . . 13

III. Ambient Air Quality and Need for Control of Sulfur Oxides
and Sulfates. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
A. Air Quality. . . . . . . . . . . . . . . . . . . . . . . . . . 16
B. Necessary Reductions in Sulfur Oxides Emissions. . . . . . . . 28
C. Visibility . . . . . . . . . . . . . . . . . . . . . . . . . . 35

IV. Impact of Gasoline Combustion Generated Sulfur Oxides on Air
Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
A. Sulfate Emissions from Catalysts . . . . . . . . . . . . . . . 36
B. Sulfur Dioxide Emissions from Gasoline Combustion. . . . . . . 37
C. Contribution of automobile Sulfur Oxide Emissions to
Ambient Sulfates Concentrations in the South Coast
Air Basin. . . . . . . . . . . . . . . . . . . . . . . . . . . 46
D. Roadway Sulfates Concentrations. . . . . . . . . . . . . . . . 53

V. Emissions and Air Quality Impacts of Rescinding the Regulation. . . 65
A. Emissions of Sulfur Oxides . . . . . . . . . . . . . . . . . . 65
B. Ambient Air Quality. . . . . . . . . . . . . . . . . . . . . . 69

VI. Economic Impact of Retaining the Regulation . . . . . . . . . . . . 72
A. Technical Aspects of Gasoline Desulfurization. . . . . . . . . 72
B. Economic Impacts . . . . . . . . . . . . . . . . . . . . . . . 80

VII. Other Impacts of Retaining the Regulation . . . . . . . . . . . . . 86

VIII. Discussion and Recommendation. . . . . . . . . . . . . . . . . 90

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Appendix A - Evaluation by the Arthur D. Little, Inc. of Air
Resources Board Staff Report 75-8-6 . . . . . . . . . . .A-1

Appendix B - Air Resources Board Resolution 75-33, Adopted June
30, 1975. . . . . . . . . . . . . . . . . . . . . . . . .B-1

Appendix C - Section 2252 of Title 13 of the California
Administrative Code . . . . . . . . . . . . . . . . . . .C-1

Appendix D - Western Oil and Gas Association Petition. . . . . . . . .D-1

Appendix E - Questionnaires to Western Oil and Gas Association
Members . . . . . . . . . . . . . . . . . . . . . . . . .E-1

Appendix F - Air Quality Models. . . . . . . . . . . . . . . . . . . .F-1

Appendix G - Emissions Inventories . . . . . . . . . . . . . . . . . .G-1

Appendix H - Gasoline Consumption. . . . . . . . . . . . . . . . . . .H-1

Appendix I - Lead as a Tracer for Automotive Sulfates. . . . . . . . .I-1

Appendix J - Review of Sulfate Formation in Exhaust Catalysts. . . . .J-1

Appendix K - Public Hearing Notice . . . . . . . . . . . . . . . . . .K-1