MOJAQMD RULE 1307 EMISSION OFFSETS
LAST REVISED 10/27/93
(Adopted: July 21, 1980) (Amended: 10/27/93)
RULE 1307
EMISSION OFFSETS
(A) Offset Thresholds
Offsets are actual emission reductions (AERs) sufficient to
mitigate emission increases of affected air pollutants from
a new or modified major facility. An affected facility
subject to the offset requirements of this rule shall
provide offsets for each facility on an annual basis.
Offsets shall be required for emissions increases from
affected facilities which emit, or have the potential to
emit, any affected air pollutant for which the District has
been designated non-attainment, equal to or exceeding the
following thresholds:
Pollutant Offset Threshold
NOx 25 tons/year
SOx 25 tons/year
ROC 25 tons/year
PM10 15 tons/year
CO 100 tons/year
H2S 10 tons/ year
Pb 0.6 tons/year
Offsets shall not be required for an existing facility when
the aggregated emissions change over any consecutive five
year period is less than 25 tons for any affected air
pollutant and the proposed potential to emit does not
represent an increase from the historic potential emissions.
(B) Determination of Offset Requirements
(1) New Major Facility
Offsets shall be required for emissions increases from
a new facility with potential to emit, calculated in
accordance with Rule 1306(D), affected pollutants or
their precursors equal to or exceeding the threshold
specified above. The amount of offsets required shall
be the total amount of emissions, on a pollutant
category specific basis, pursuant to Rule 1306(D).
(2) Existing Facility
Offsets shall be required for emissions increases from
a modified facility under the following conditions:
Non-major Facility
(a) An existing facility which has a potential to
emit, pursuant to 1306(C), less than the
thresholds specified above for affected air
pollutants or their precursors, shall offset that
portion of the facility's potential to emit,
pursuant to 1306(D), which exceeds the threshold
for new or modified permit units.
Major Facility
(b) A facility's potential to emit shall be
calculated in accordance with Rule 1306(C).
After the potential to emit for an affected
facility has exceeded the facility's historic
potential emssions as of October 27, 1993, and
the applicant has provided actual emissions
reductions to offset emission increases in excess
of these levels, all future increases from new or
modified permit units shall be offset; and
(c) An existing affected facility shall offset any
increases in potential to emit, calculated
pursuant to Rule 1306(D), resulting from the
permitting of any new or modified permit unit.
(3) Seasonal Sources
(a) New or modified seasonal facilities shall provide
offsets on a quarterly basis.
(b) Seasonal emissions used for offsets shall
generally occur during the same consecutive
monthly period as the new or modified facility
operates.
(C) Location of Offsets and Offset Ratios
An affected facility shall provide offsets for the net
emissions increase on a pollutant category specific basis,
calculated in accordance with Rule 1306(D) and multiplied by
the appropriate offset ratio listed in the following table:
Table of Offset Ratios
POLLUTANT OFFSET RATIO
Reactive Organic Compound (ROC) 1.0 TO 1.0*
1.3 TO 1.0**
Oxides of nitrogen (NOx) 1.0 to 1.0*
1.3 to 1.0**
Oxides of sulfur (SOx) 1.0 to 1.0
PM10 1.0 to 1.0
Carbon monoxide (CO) 1.0 to 1.0
Hydrogen sulfide (H2S) 1.0 to 1.0
Lead (Pb) 1.0 to 1.0
* When located in a Federal Ozone Attainment Area
** When located in a Federal Ozone Non-attainment Area
the offsets must be obtained from facilities within
the same Non-attainment Area
(D) Modeling For Offset Purposes
(a) Offset Requirements for Increases in Attainment
Pollutants
Offsets shall not be required for increases in
attainment pollutants if the applicant demonstrates to
the satisfaction of the APCO, through an impact
analysis, that the ambient air quality standards are
not violated in the areas to be affected, and such
emissions will not cause or contribute to a violation
of ambient air quality standards.