AMAAPCD RULE 411 EMISSION OFFSET ELIGIBILITY
LAST REVISED 11/11/11

Rule 411  Emission Offset Eligibility.

     A.   Except in the case of seasonal sources, emissions
          offset quantities shall be calculated on annual, and
          daily bases.  For seasonal sources, emission offset
          quantities shall be calculated on the basis of the
          season date span of operation, and daily emission rate,
          either estimated for proposed sources or averaged over
          the two year period preceding the date of application,
          or other appropriate periods as determined by the Air
          Pollution Control Officer, for existing sources.

     B.   Emission offsets may be developed by the reduction of
          emissions from existing stationary, and non-stationary
          sources.  Offsets from stationary sources not exempt
          from the provisions of Rule 501 shall be certified by
          the Air Pollution Control Officer through conditions
          attached to the Permits to Operate of the emission-
          reducing sources.  Offsets from non-stationary sources,
          and exempt stationary sources shall be certified by the
          Air Pollution Control Officer through new facility
          Permit to Operate conditions, contracts, or other means
          deemed adequate by the Air Pollution Control Officer. 
          Such emissions offsets shall take effect no later than
          120 days after initial operation of the new facility or
          modification.

     C.   The ratio of emission offsets to the emission from a
          new facility or modification shall be:

          1.   1.0:1 for offsets within the facility;

          2.   1.2:1 for offsets upwind in the same or adjoining
               Air Pollution Control District, or within a 15
               mile radius of the proposed new facility or
               modification.

          3.   Sufficient to demonstrate an air quality benefit
               through modeling in the area affected by emissions
               from the new facility or modification for offsets
               located in areas other than those of 1. or 2.
               above.

     D.   If an applicant certifies that the proposed new
          facility or modification is a replacement for a
          facility or source which was shut down or curtailed
          after January 1, 1981, emission reductions associated
          with such shutdown or curtailment may be used as
          offsets for the proposed facility or modification. 
          Sources which were shut down or curtailed prior to
          January 1, 1981, may be used to offset emissions
          increases for replacements for such sources, provided
          that:

          1.   The shutdown or curtailment was made in good faith
               pursuant to an established plan with the Air
               Pollution Control Officer for replacement and
               emission control, and in compliance with air
               pollution laws, rules and regulations at the time;
               and

          2.   The applicant demonstrates to the satisfaction of
               the Air Pollution Control Officer that there was
               good cause for delay in construction of the
               replacement sources.

     E.   Notwithstanding any other provisions of this rule, any
          emissions reductions not otherwise authorized by this
          Rule may be used as offsets or emission increases from
          the pro- posed facility or modification provided that
          the applicant demonstrates to the satisfaction of the
          Air Pollution Control Officer that such reductions will
          result in a net air quality benefit in the area
          affected by emissions from the new facility or
          modification.

     F.   Emissions reductions resulting from measures required
          by adopted federal, state, or District laws, rules or
          regulations shall not be allowed as emissions offsets
          unless a complete application incorporating such
          offsets was filed with the District prior to the date
          of adoption of the laws, rules or regulations.

     G.   Emissions reductions of one precursor may be used to
          offset emissions increases of another precursor of the
          same secondary pollutant provided that the applicant
          demonstrates to the satisfaction of the Air Pollution
          Control Officer that the net emission increase of the
          latter precursor will not cause a new violation, or
          contribute to an existing violation, of any national
          ambient air quality standard.  The ratio of emission
          reductions between precursor pollutants of the same
          secondary pollutant shall be determined by the Air
          Pollution Control Officer based upon existing air
          quality data.