CALIFORNIA ENVIRONMENTAL PROTECTION AGENCY
AIR RESOURCES BOARD
Air Resources Board
Board Hearing Room, Lower Level
2020 "L" Street
October 14, 1993
93-12-1 Public Meeting to Consider Approval of the 001
Chico Urban Area Carbon Monoxide Plan, as
Required by the California Clean Air Act of 1988.
93-12-2 Public Hearing to Consider the Adoption of an 019
Airborne Toxic Control Measure for
Perchloroethylene Emissions from Dry Cleaning
Operations and a Regulation for an Environmental
Training Program for Perchloroethylene Dry
ITEM NO.: 93-12-1
Public Meeting to Consider Approval of the Butte County Air
Pollution Control District's Carbon Monoxide Plan for the Chico
Urban Area, as Required by the California Clean Air Act of 1988.
Approve the Chico Urban Area Carbon Monoxide Plan.
Carbon monoxide emissions in the Chico urban area are
overwhelmingly motor vehicle in origin. The carbon monoxide
standard is exceeded infrequently and only by a small margin.
Violations have been limited to a single downtown monitoring
Staff's evaluation indicates that the plan satisfies all but one
of the California Clean Air Act (Act) requirements. Emission
reductions from the existing Air Resources Board regulations for
motor vehicles and fuels (including wintertime oxygenated fuel)
are expected to bring the area into attainment by 1994, without
the need for further state or local action.
The plan discusses additional local measures such as traffic flow
improvements, park, and ride lots, and land use planning
policies. The plan commits to considering the feasibility of
such measures and to promoting use of public transportation. To
the extent such measures are implemented, additional benefits in
terms of both carbon monoxide and ozone air quality will accrue.
Staff believes that the plan meets all the Act's requirements.
The District's permitting program has a best available control
technology (BACT) threshold of 25 pounds per day rather than the
50 pounds per day specified in the Act; however, more stringent
stationary source measures are not needed for attainment. Thus,
staff recommends that the Board find that the plan meets the
Act's permitting requirements for carbon monoxide to the extent
necessary for attainment of the state standard.
SUMMARY AND IMPACTS
Carbon monoxide emission reductions totaling about 21% from the
1987 baseline are projected to result from state motor vehicle
and fuel regulations through the year 1994. These reductions are
expected to bring the Chico area into attainment for the carbon
monoxide standard by 1994.
ITEM NO.: 93-12-2
Public Hearing to Consider the Adoption of an Airborne Toxic
Control Measure for Perchloroethylene Emissions from Dry Cleaning
Operations and a Regulation for an Environmental Training Program
for Perchloroethylene Dry Cleaning Operations.
The staff recommends the Board adopt the proposed airborne toxic
control measure for perchloroethylene (Perc) emissions from dry
cleaning operations (proposed dry cleaning regulation) and the
proposed regulation for the environmental training program for
Perc dry cleaning operations (proposed training regulation).
The Board identified Perc as a toxic air contaminant (TAC) with
no identifiable threshold level. The dry cleaning industry is
the major user of Perc. Other uses of Perc are in consumer and
industrial products, degreasing operations, paints and coatings,
and adhesives. In the state, we estimate that the dry cleaning
industry used about one million gallons of Perc in 1991, with
742,000 gallons being emitted into the atmosphere.
In dry cleaning operations, four basic types of machines are
used. They are transfer machines, vented machines, closed-loop
machines, and converted machines. For the same volume of clothes
cleaned, closed-loop machines use and emit the least amount of
Perc of any machine type. In comparison, converted machines emit
about twice as much Perc as a closed-loop machine, vented
machines almost three times as much, and transfer machines about
four times as much. Of the 4,800 estimated dry cleaning plants
in the state, about one-half of the machines are closed-loop
machines, about one-third are vented machines, less than ten
percent are transfer machines, and about five percent are
In dry cleaning operations, Perc may be lost through process or
fugitive emissions, disposed of in the waste, discharged to the
sewer, or retained in the clothes. Perc is lost to the
atmosphere from several sources. Transfer and vented machines
have process emissions, in which Perc is exhausted to the
atmosphere at the end of the drying cycle. Closed-loop and
converted machines do not exhaust Perc vapors to the atmosphere
and, therefore, have no process emissions. Fugitive emissions
can occur from all types of dry cleaning machines. Fugitive
emissions include liquid and vapor leaks, residual Perc in the
clothes, waste distillation and recovery operations, Perc vapors
escaping from the opening of machine doors or other access
openings, spotting and pressing operations, and water-repelling
The exhaust from transfer and vented machines is usually
controlled with carbon adsorbers. Almost all closed-loop and
converted machines use refrigerated condensers to recover Perc
during the drying cycle. About 95 percent of the machines in the
state are equipped with refrigerated condensers or carbon
adsorbers for Perc recovery and emission control.
The estimated potential statewide cancer burden attributable to
Perc from dry cleaning operations is about 250 potential cases
over 70 years. The potential maximum individual risk near most
dry cleaners today ranges from about 50 to 500 chances in a
million. The existing risk near dry cleaners with the highest
potential risk is estimated to be about 1,000 to 2,000 chances in
a million. The potential risk to people living in the same
building as a dry cleaning facility (co-located) may be a
significantly higher risk than the risk of people living near the
SUMMARY AND IMPACTS
The staff developed the proposed regulations in consultation with
the affected industry and the districts. The process included
releasing draft versions of the regulations and supporting
information for public comments, conducting four sets of public
workshops, and instituting an extensive public outreach program
with individual dry cleaners and industry associations through
meetings and telephone calls. For the Korean dry cleaners, we
provided a Korean translation of key documents and met with them
in small groups to discuss the impacts of the proposed
The proposed dry cleaning regulation sets forth the equipment,
training, maintenance, and other requirements for Perc dry
cleaning operations. In consideration of cost and risk, the
staff is proposing that the best available control technology
(BACT) for an existing facility be a closed-loop machine or a
vented machine converted to a closed-loop machine. The staff is
proposing that BACT for a totally new dry cleaning facility be a
closed-loop machine with a secondary control system. The staff
is not proposing that secondary control systems be required on
new machines which are replacing old machines at existing
The proposed training regulation establishes the criteria for the
Air Resources Board to authorize environmental training programs
and instructors who want to offer the environmental training
courses that are required by the dry cleaning regulation.
On a statewide basis, the proposed regulations will reduce Perc
emissions and potential risk to Perc by about 75 percent. Perc
emissions would be reduced from 742,000 gallons to about 164,000
gallons. The potential cancer burden would be reduced from 250
cases over 70 years to 55 cases over 70 years. The proposed
regulations would also reduce the potential cancer risk from
about 50 to 500 chances in a million to about 10 to 90 chances in
a million at most existing dry cleaners.
For new dry cleaners, improved operating practices and the
addition of a secondary control system to a closed-loop machine
with a refrigerated condenser could reduce the potential residual
cancer risk by 80 percent. The typical risk at new dry cleaners
today is about 25 to 100 chances in a million; the potential risk
for new dry cleaners after implementation of the proposed
regulations would be about five to 20 chances in a million.
The annualized cost of the proposed regulations to most dry
cleaners would range from $300 to $3,000 per year for a typical
facility that has about $240,000 in gross receipts. The total
statewide annual cost to all dry cleaners is estimated to be just
under $5 million per year, for an industry with gross receipts of
about $1 billion per year.
In addition to the reduction in potential cancer cases and
emissions, the proposed regulations would reduce worker exposure
to Perc and reduce the generation of hazardous waste.
Potential adverse environmental impacts associated with the
proposed regulations are: (1) minor increases in power plant
emissions due to increased electrical demand to operate new or
converted machines, and (2) minor increases in the use of
refrigerants to operate refrigerated condensers.