Surface and Precipitation Stations - New Mexico Environment ...

• All particulate modeling will be performed using 1 gram per second nominal emission rates
in CALPUFF for the specific size ranges presented in the NPS speciation spreadsheets (i.e.,
PM8.0, PM4.25, PM1.88, PM1.25, PM0.813, and PM0.625). These modeled species will be grouped
in POSTUTIL as to represent the appropriate visibility pollutants (e.g., PMcourse = PM8.0 +
PM4.25 and PMfine = PM1.88 + PM1.25 + PM0.813 + PM0.625) and will be scaled with the
emission rates derived from the NPS spreadsheets. EC and SOA will be derived from the
PM1.88 species and scaled with the emission rates derived from the NPS spreadsheets.
2.2.1.1 H2SO4 (SO4) Emissions
Condensable PM10 will be subdivided into inorganic and organic compounds using the NPS
speciation spreadsheets. The inorganic portion is by default assumed to be H2SO4 and will me
modeled as SO4. The organic portion will be modeled as secondary organic aerosols (SOA).
2.2.2 Post Control Modeling
As required by EPA guidance, each technically feasible BART control technology must be assessed
to determine the degree of visibility improvement. These relative improvements from various
technologies and/or control levels can then be factored into the BART decision. At this time, the
evaluation of technically feasible controls (Step 4 of the BART process) has not been completed and
it is unknown how many feasible control technologies options are available for consideration.
However once determined, each technically feasible control for each pollutant will be modeled on a
unit by unit basis.
For the purpose of this PNM Protocol NOx and PM10 are the only pollutants subject to BART
analyses. Due New Mexico participating in a trading program for SO2, a SO2 BART analysis is not
required and will not be modeled as a separate feasible control technology option. However, SO2
emissions will be included as a modeled pollutant as part of both the baseline and post control
modeling scenarios. PM10 emissions will be speciated as described in the baseline modeling section.
The stack parameters and emission rates used for the post control modeling for each unit, pollutant,
and technology will be determined and presented in the final report submitted to NMED.
2.3 Model Versions
The versions of the CALPUFF modeling system suggested in the WRAP Protocol and used by
WRAP RMC for the initial modeling will be used for these modeling analyses and are listed in Table
2-3.
2-6 4/13/2007