Current through Register Vol. 48, No. 6, March 25, 2025
II.A.
Definitions
II.A.1. "8-Hour Ozone Control
Area" means the Counties of Adams, Arapahoe, Boulder (includes part of Rocky
Mountain National Park), Douglas, and Jefferson; the Cities and Counties of
Denver and Broomfield; and the following portions of the Counties of Larimer
and Weld:
II.A.1.a. For Larimer County
(includes part of Rocky Mountain National Park), that portion of the county
that lies south of a line described as follows: Beginning at a point on Larimer
County's eastern boundary and Weld County's western boundary intersected by 40
degrees, 42 minutes, and 47.1 seconds north latitude, proceed west to a point
defined by the intersection of 40 degrees, 42 minutes, 47.1 seconds north
latitude and 105 degrees, 29 minutes, and 40.0 seconds west longitude, thence
proceed south on 105 degrees, 29 minutes, 40.0 seconds west longitude to the
intersection with 40 degrees, 33 minutes and 17.4 seconds north latitude,
thence proceed west on 40 degrees, 33 minutes, 17.4 seconds north latitude
until this line intersects Larimer County's western boundary and Grand County's
eastern boundary.
II.A.1.b. For
Weld County, that portion of the county that lies south of a line described as
follows: Beginning at a point on Weld County's eastern boundary and Logan
County's western boundary intersected by 40 degrees, 42 minutes, 47.1 seconds
north latitude, proceed west on 40 degrees, 42 minutes, 47.1 seconds north
latitude until this line intersects Weld County's western boundary and Larimer
County's eastern boundary.
II.A.2. "Denver 1-Hour Ozone
Attainment/Maintenance Area" means the Counties of Jefferson and Douglas, the
Cities and Counties of Denver and Broomfield, Boulder County (excluding Rocky
Mountain National Park), Adams County west of Kiowa Creek, and Arapahoe County
west of Kiowa Creek.
II.A.3.
"Northern Weld County" means the portion of the county that does not lie south
of a line described as follows: Beginning at a point on Weld County's eastern
boundary and Logan County's western boundary intersected by 40 degrees, 42
minutes, 47.1 seconds north latitude, proceed west on 40 degrees, 42 minutes,
47.1 seconds north latitude until this line intersects Weld County's western
boundary and Larimer County's eastern boundary.
II.A.4. "Volatile Organic Compound (VOC)"
means any compound of carbon, excluding carbon monoxide, carbon dioxide,
carbonic acid, metallic carbides or carbonates, and ammonium carbonate, which
participates in atmospheric photochemical reactions, except those listed in
Section II.B. as having negligible photochemical reactivity. VOC may be
measured by a reference method, an equivalent method, an alternative method, or
by procedures specified under 40 CFR Part 60 (July 1, 2022). A reference
method, an equivalent method, or an alternative method, however, may also
measure nonreactive organic compounds. In such cases, an owner or operator may
exclude the compounds listed in Section II.B. when determining compliance with
a standard if the amount of such compounds is accurately quantified, and such
exclusion is approved by the Division. As a precondition to excluding such
compounds as VOC, or at any time thereafter, the Division may require an owner
or operator to provide monitoring or testing methods and results demonstrating,
to the satisfaction of the Division, the amount of negligible-reactive
compounds in the source's emissions.
II.B. Exemptions
Emissions of the organic compounds listed as having
negligible photochemical reactivity in the common provisions definition of
Negligibly Reactive Volatile Organic Compound are exempt from the provisions of
this regulation. However, the hydrocarbon threshold in Part B, Section I.L. and
natural gas emissions standards in Part B, Sections III.C.1. and III.C.2. are
used as indicators for the volatile organic compound emission reduction
measures in Part B, Sections I.L., III.C.1., and III.C.2., and are enforceable
provisions of this regulation.
(State Only) Notwithstanding the foregoing exemption,
hydrocarbon emissions from oil and gas operations, including methane and
ethane, are subject to this regulation as set forth in Part B.
II.C. New Sources
All new sources shall utilize controls representing RACT,
pursuant to applicable provisions in Regulation Number 7, Regulation Number 24,
Regulation Number 25, Regulation Number 26 and Regulation Number 3, Part B,
Section III.D., upon commencement of operation.
II.D. Alternative Control Plans and Test
Methods
II.D.1. Sources subject to specific
requirements of this regulation shall submit for approval as a revision to the
State Implementation Plan:
II.D.1.a. Any
alternative emission control plan or compliance method other than control
options specifically allowed in the applicable regulation. Such alternative
control plans shall provide control equal to or greater than the emission
control or reduction required by the regulation, unless the source contends
that the control level required by the regulation does not represent RACT for
their specific source.
II.D.1.b.
Any alternative test method or procedure not specifically allowed in the
applicable regulation.
II.D.2. No alternative submitted pursuant to
this Section II.D. is effective until the alternative is approved as a revision
to the State Implementation Plan.
