TUOLUMNE COUNTY AIR POLLUTION CONTROL DISTRICT
RULE 427 - CONSTRUCTION OR RECONSTRUCTION OF MAJOR STATIONARY SOURCES THAT EMIT HAZARDOUS AIR POLLUTANTS
(Adopted 06/01/99)
A. Purpose
To require all owners and operators of stationary sources that emit hazardous air pollutants (HAPs) to install
best available control technology for toxics (T-BACT) to any constructed or reconstructed major source. All T-BACT
determinations shall be controlled to a level that the Air Pollution Control Officer (APCO) has determined to be,
at a minimum, no less stringent than new source maximum achievable control technology (MACT) as required by the
federal Clean Air Act (CAA), §112 (g)(2)(B) and implemented through 40 CFR §§63.40-63.44, of subpart
B.
B. Applicability
The requirements of this rule shall apply to all owner or operators that construct or reconstruct a major source
of HAPs, unless the major source is exempt pursuant to section C.
Compliance with this rule does not relieve any owner or operator of a major source of HAPs from complying with
all other District rules or regulations, any applicable State airborne toxic control measure (ATCM), or other applicable
State and federal laws.
C. Exemptions
This rule does not apply to any of the following exclusions:
D. Effective Date
This rule is effective on date of rule adoption, but no later than June 29, 1999.
E. Definitions
Terms used in this rule that are not defined in this section have the meaning given to them in 40 CFR §63.40
through 63.44.
Best Available Control Technology for Tonics (T-BACT): the most effective emissions limitation or control technique
which:
Construct a Major Source: the same as defined in 40 CFR §63.41 Definitions.
Hazardous Air Pollutants (HAPS): any air pollutant listed in or pursuant to federal CAA, §112(b).
Major Source of HAPs: any stationary source or group of stationary sources located within a contiguous area and
under common control that emits or has the potential to emit considering controls, in the aggregate, 10 tons per
year or more of hazardous air pollutants or 25 tons per year or more of any combination of hazardous air pollutants.
Potential to Emit: The maximum capacity of a stationary source to emit a pollutant under its physical and operational
design. Any physical or operational limitation on the capacity of the stationary source to emit a pollutant, including
air pollution control equipment and restrictions on hours of operation or on the type or amount of material combusted,
stored, or processed, shall be treated as part of its design if the limitations or the effect it would have on
emissions are incorporated into the applicable permit as enforceable permit conditions.
Reconstruct a Major Source: the same as defined in 40 CFR §63.41 Definitions.
F. T-BACT Requirements
T-BACT shall be installed on any source that meets the definition of "construct a major source" or "reconstruct
a major source" as defined in 40 CFR §63.41. The potential to emit of a constructed or reconstructed
major source shall be calculated pursuant to section G.
G. Calculation Procedures
The potential to emit for a source of HAPs shall equal the sum of the potentials to emit of the constructed or
reconstructed source of HAPs. All fugitive HAP emissions associated with the construction or reconstruction shall
be included in the potential to emit determination.
H. Administrative Procedures
An application for authority to construct a major source or reconstruct a major source of HAPs shall be subject
to the administrative procedures contained in Tuolumne County Air Pollution Control District Rule 403 - Applications.