CALIFORNIA AIR RESOURCES BOARD
Auditorium, First Floor
400 "P" Street
August 8, 1991
91-6-1 Public Hearing to Consider the Adoption of a 001
Regulatory Amendment Identifying Nickel (Metallic
Nickel and Inorganic Nickel Compounds) as a Toxic
91-6-2 Public Hearing to Consider Amendments to the 016
Agricultural Burning Guidelines.
91-6-3 Public Meeting to Consider Approval of the Final 042
Report of the Locomotive Emission Advisory Committee
Regarding the Feasibility and Cost-Effectiveness of
Controlling Emissions from Locomotives Operated in
91-6-4 Public Meeting to Consider a Regulatory Plan for 057
the Control of Locomotive Exhaust Emissions.
ITEM NO.: 91-6-1
Proposed Identification of Nickel as a Toxic Air Contaminant
The ARB staff recommends that nickel be identified as a toxic air
contaminant without a specified threshold exposure level.
In accordance with the provisions of Health and Safety Code
section 39650 et seq., the ARB staff, after consulting the
Department of Health Services (DHS), selected nickel for the
Board's consideration for listing as a toxic air contaminant.
The staff selected nickel for the following reasons: The IARC has
classified nickel compounds in a group 1 (associated with cancer
in humans); the US EPA lists nickel refinery dust and nickel
subsulfate in group A (known human carcinogen); there are a wide
variety of sources in California; and, nickel is mobile in the
environment and is not naturally removed or detoxified at a rate
that would significantly reduce public exposure. In addition,
nickel has been listed as a Hazardous Air Pollutant under section
112 of the U.S. Clean Air Act and as required by Health and
Safety Code section 39655, must be identified as a toxic air
As required by Health and Safety Code section 39661, a report was
prepared jointly by the ARB and DHS staffs. This report reviewed
the exposure levels and health effects of exposure to nickel in
California. The major source of nickel is fossil fuel
combustion. Other sources are: asbestos mining and milling,
secondary smelting, municipal refuse and sewage sludge
incineration, electroplating, and cement manufacturing. Exposure
to nickel is associated with increased respiratory cancer.
The estimated unit risk for continuous lifetime exposure to 1
microgram per cubic meter for nickel ranges from 1.9 x 10-4 to
37x10-4. Using data from the California ARB air toxics
monitoring network, the population-weighted annual nickel
exposure was estimated to be 7.3 nanograms per cubic meter and
the staff estimates the excess carcinogenic risk from a lifetime
exposure to be from 1.4 to 27 potential cancer cases per million.
The DHS' best value unit risk factor for nickel is 2.6 x 10-4 per
microgram per cubic meter which results in a best estimate,
lifetime potential cancer risk from exposure to nickel of 2
cancer cases per million and, assuming a statewide population of
30 million, 60 potential excess cancer cases statewide.
"Hot spot" exposure to airborne nickel may increase the risk of
respiratory cancer. The result of modeling emissions from fuel
combustion facilities show that exposures near these facilities
are likely to be about 10 times higher than the statewide
The Scientific Review Panel (SRP) reviewed the report, and found
the nickel report is without serious deficiency and submitted its
written findings to the Board. The SRP has recommended that the
Board list nickel by regulation as a toxic air contaminant, and
found that, based on available scientific information, nickel
exposure does not have a threshold below which carcinogenic
effects are not expected to occur.
IMPACTS OF PROPOSED BOARD ACTION
The identification of nickel as a toxic air contaminant will not
in itself have any environmental and economic impacts. However,
specific control measures may be developed subsequent to
identification and analysis of potential environmental and
economic impacts will be included in the consideration of such
ITEM NO.: 91-6-2
Public Hearing to Consider Amendments to the Agricultural Burning
The staff proposes that the Board amend the Agricultural Burning
Guidelines as follows: (1) modify the reporting requirements to
reduce the frequency of reports for some areas and to change the
information to be reported, making these reports uniform for all
areas of the state; (2) correct obsolete language describing a
portion of Placer County now in the Sacramento Valley Air Basin;
and (3) replace references in the Guidelines to the federal
ambient air quality standards with references to the state
The following sections of Title 17, California Code of
Regulations, would be amended: (1) section 80130 (reporting
requirements); (2) sections 80150, 80250, and 80290 (references
to portion of Placer County) and (3) sections 80250 and 80260
(references to ambient standards.)
The current guidelines require that districts submit reports to
the Board on the types and amounts of agricultural wastes burned.
Districts in the San Joaquin Valley and the Sacramento Valley
must submit these reports quarterly. The reports must identify
the types and amounts of agricultural waste burned on each day.
Districts in the rest of the state must report annual summaries
of the types and amounts of waste burned.
The proposed amendments would require all districts to submit
annual reports of the total amounts of waste burned each month.
The districts would have to identify specific types of crop
wastes burned for at least 80 percent of the total waste.
Reporting would be simplified because districts would no longer
have to submit reports on the daily amounts and types of wastes
burned, nor would they have to specify corp types for minor
amounts of wastes burned. Provisions authorizing modifications
to the frequency of reports would also be revised.
These reports would provide the data in a format more useful to
the Board's staff. These data will be useful for attainment
planning purposes to meet the California Air Quality Standards
and to allow further evaluation of the agricultural burning
A 1986 amendment to the air basin boundaries placed the western
portion of Placer County in the Sacramento Valley Air Basin.
However, some provisions in the Guidelines still refer to the
western portion of Placer County as a part of the Mountain
Counties Air Basin; these provisions are now outdated and would
The Guidelines also require that when a no-burn day decision is
declared in the Sacramento Valley and San Joaquin Valley Air
Basins and the federal ambient standards for specified pollutants
are expected to be exceeded, a statement to that effect shall be
appended to the announcement. The proposed amendments would
replace the references to federal ambient standards with
references to state ambient standards. The reason for these
proposed amendments is that the California Clean Air Act places
increases importance on state ambient standards.
SUMMARY AND IMPACTS
In preparing the proposal, the staff held a workshop and
discussed the proposed modifications to the reporting
requirements for agricultural burning. Based on these
discussions and the subsequent comments received, the staff
believes that there are no significant adverse environmental or
cost impacts that would result from the proposed regulations.
The amendments are expected to result in a uniform reporting
format for the entire state, thereby making these data more
useful to all interested parties.
ITEM NO.: 91-6-3
Public Meeting to Consider Approval of the Final Report of the
Locomotive Emission Advisory Committee Regarding the Feasibility
and Cost-Effectiveness of Controlling Emissions from Locomotives
Operated in California.
Staff recommends that the Air Resources Board (the "Board" or
"ARB") approve the Locomotive Emission Study for submission to
the Governor and Legislature.
Section 5 of Chapter 1326 of the Statutes of 1987, as referenced
in Health and Safety Code Section 43013(d), mandated the ARB, in
conjunction with the railroad industry, to conduct a study of
locomotive emissions. The legislation requires that the study
include a survey of past research into the subject of locomotive
emissions, current technology available to reduce those
emissions, a cost/benefit analysis regarding the economic impact
on the railroad industry of using present and proposed
technology, and consideration of public and employee safety
issues that may result from the use of these technologies. The
statute further provides that the study shall be directed by, and
study and project report and recommendations adopted by a
Locomotive Emission Advisory Committee, composed of government
and industry representatives.
The Locomotive Emission Advisory Committee contracted the study
at a cost of $128,000 to Booz, Allen and Hamilton, Inc., a firm
with extensive consulting experience with the rail industry and
in mobile source emission control technology. The study was
jointly funded by the ARB, the South Coast Air Quality Management
District, and the Southern Pacific Transportation Company. In
addition, data of considerable value to the study were collected
and provided by the railroad industry at its own expense. Booz,
Allen and Hamilton, Inc., has completed the study and final
report, entitled "Locomotive Emission Study." The final report
has been reviewed by the Locomotive Emission Advisory Committee
and approved by a majority vote of its members.
The goals of the study were threefold: 1) to produce an updated
and accurate inventory of locomotive emissions in order to assess
their significance, relative to other sources; 2) to determine if
existing and proposed emission control techniques can achieve
significant, cost-effective emission reductions; and 3) if this
determination is positive, to make recommendations for a
subsequent demonstration project of promising technologies.
SUMMARY OF IMPACTS
The California Clean Air Act (Health and Safety Code Sections
43013 and 43018) mandates that the Board consider the adoption of
emission regulations for several currently unregulated mobile
sources, including the locomotive fleet which operates within the
State. As required by the California Clean Air Act, the
Locomotive Emission Study must be completed and submitted to the
Governor and Legislature before the Board may adopt any standard
or regulation affecting locomotives.
The 1990 reauthorization of the Federal Clean Air Act preempted
California's authority to regulate new locomotives and new
locomotive engines. Therefore, any locomotive emission control
regulations to be considered by the Board must focus on the
existing locomotive fleet. Using the information provided by the
Study, as well as consultation with industry, public agencies,
and other experts, staff has developed a control plan for
reducing emissions from locomotives operating within the State.
The control plan presents the regulatory options for reducing
locomotive emissions. A formal regulatory proposal would follow
ITEM NO.: 91-6-4
Public Meeting to Consider a Regulatory Plan for the Control of
Locomotive Exhaust Emissions.
The staff recommends that the Air Resources Board (ARB or Board)
approve the staff's regulatory plan for controlling locomotive
The California Clean Air Act (CCAA) as codified in Health and
Safety Code Sections 43013 and 43018 grants the ARB authority to
regulate emissions from off-road vehicles and other mobile
sources including locomotive in order to achieve reductions in
hydrocarbons (HC), oxides of nitrogen (NOx), carbon monoxide
(CO), particulate (PM), and toxic air contaminants.
The California locomotive exhaust emissions inventory for 1987 is
estimated to be 99 tons per day (tpd) NOx, 4 tpd HC, 13 tpd CO, 7
tpd sulfur oxides (SOx), and 2 tpd PM. It is estimated that the
locomotive contribution is equivalent to nearly five percent of
the NOx, three percent of the SOx, and one percent of the PM
mobile source statewide emissions inventory. Moreover, as
stationary and mobile source control measures are implemented,
the locomotive NOx emission contribution will increase to 6.2
percent of the total mobile emissions by 2010.
To fulfill the statutory requirements under the CCAA, the staff
has prepared a regulatory plan for controlling locomotive exhaust
emissions. The regulatory plan identifies those control measures
the staff considers feasible and ready for regulatory
developemnt. Upon approval by the Board, the staff will develop
a formal regulatory proposal for consideration at a future Board
Much of the information used to develop the regulatory plans was
obtained from the Locomotive Emission Study. Section 5 of AB 234
(1987) directed the ARB and the California railroad industry to
undertake this study. This law also provided for a Locomotive
Emissions Advisory Committee (LEAC) to direct the study and
approve the final report. The report has been completed and
submitted to the ARB for its approval and transmittal to the
Legislature and Governor.
Several engine modification and operational options were
identified in the LEAC study as potential emission control
options. These are: fuel injection timing retardation; fuel
injector retrofit; low sulfur diesel fuel; and reduced idle time.
Emissions standards for new engines are not being considered
since the Federal Clean Air Act preempts the ARB from adopting
A second approach discussed in the control plan is a market based
cotrol (MBC) strategy. This approach allows flexibility, and
provides economic incentives to reduce emissions beyond required
levels through the use of marketable permits. Flexibility is
inherent in this approach because the locomotive companies can
determine the most cost-effective control strategies for their
specific circumstances. Marketable permits provide an incentive
to reduce emissions beyond the mandated levels if these
reductions can be made at a cost of less than the market rate for
the permits. The MBC strategy thus encourages the maximum
emission reductions possible.
The staff believes that additional time is necessary to fully
develop these approaches and the regulatory language. In
addition, Board approval of the LEAC report is prerequisite to
the adoption of any formal regulation for locomotive emissions.
SUMMARY AND IMPACTS
Regulations may be developed to significantly reduce locomotive
exhuast emissions. This control plan discusses two regulatory
approaches that could be pursued. Both appear to be viable
alternatives at this time, with maximum feasible NOx reductions
of up to 30 percent compared to baseline levels.