A.
General
Requirement. It shall be the burden of any applicant to provide an
affirmative demonstration that its emissions, in conjunction with all other
sources, will not violate ambient air quality standards, except that Part 70
sources in nonattainment areas or which significantly impact a nonattainment
area shall be required to demonstrate that the Part 70 source's emissions are
consistent with Reasonable Further Progress provisions of the State
Implementation Plan. An applicant may use ambient air monitoring, modeling, or
other assessment techniques as approved by the Department and shall be
consistent with EPA regulations and guidelines or other requirements under the
CAA. The analyses shall include relevant emissions units at the Part 70 source,
meteorological and topographical data necessary to estimate such impacts, and
shall consider the impact of fugitive emissions to the extent quantifiable,
secondary emissions, and emissions from other existing sources including
increases in mobile and area source emissions impacting the same area.
The level of analysis shall depend upon the size of the Part
70 source, the regulated air pollutants emitted, existing air quality,
proximity to Class I or nonattainment areas, or areas where increment has been
substantially consumed. (For the purposes of this subsection, the Class I area
includes any conservation easements under the jurisdiction of an appropriate
Federal Land Manager as of August 7, 1977.) The air quality impact analysis, in
general, will not be required of the applicant for those regulated pollutants
that are not included in the definition of "significant emissions increase" in
06-096 C.M.R. ch. 100. The analysis shall be conducted pursuant to subsection
14(C) of this Chapter, Prohibited Dispersion Techniques,
06-096 C.M.R. ch. 116, and Appendix W to 40 C.F.R. Part 51 - Guideline on Air
Quality Models.
Air quality modeling conducted as part of the licensing of a
new Part 70 source or modification to a Part 70 source in the United States is
substantially governed by the Appendix W to 40 C.F.R. Part 51 - Guideline on
Air Quality Models. That modeling guidance was first promulgated in 1978 and,
by law, must be routinely updated by EPA. Thus, federal regulatory guidance on
modeling and the list of acceptable models do change. The Department recognizes
that air dispersion modeling guidance will be periodically updated to reflect
the latest federal guidance. To maintain an orderly licensing process in the
State, applicants will be required to conform with those procedures and
guidelines in effect at the time of Department approval of a written modeling
protocol that meets all applicable requirements provided the applicant
completes modeling, as approved, and submits its results within six months of
the date of approval of the protocol. If the protocol calls for collection of
on-site meteorological data, then the starting date for the on-site data
collection must be no later than six months after approval of the protocol, and
modeling results must be submitted within six months of obtaining acceptable
on-site meteorological monitoring data. Requests by the applicant to modify the
modeling protocol will require conformance with current applicable air
dispersion modeling guidance.
(1)
Ambient Air Quality Monitoring Requirements. Monitoring done by
the owner or operator shall conform to the requirements of 40 C.F.R. Part 58, Appendix B and the Department's Quality Assurance Plan (or other plan approved
by the Department) during the operation of monitoring stations. It is
recommended that a written protocol be developed by the owner or operator and
the Department when a Part 70 source is required to conduct either
pre-construction or post-construction monitoring. The protocol shall, at a
minimum, specify the monitoring sites, frequency of sampling, data recovery,
pollutants, and monitoring method(s).
(2)
Air Quality Impact Modeling
Requirements(a) All estimates of
ambient concentrations required by an ambient or increment impact analysis
shall be based on the relevant air quality models, data bases, and other
requirements specified in the current Appendix W to 40 C.F.R. Part 51 -
Guideline on Air Quality Models, and in accordance with subsection 14(C) of
this Chapter, and 06-096 C.M.R. ch. 116. Fugitive emissions, to the extent
quantifiable, shall be considered.
(b) All input, output and diagnostic files
used in the final Class I and Class II standards and increment compliance
modeling analyses and Class I AQRV and visibility modeling analyses shall be
submitted to the Department on media formatted for use by computer software
which the Department uses unless otherwise approved by the
Department.
(c) Where an air
quality impact model specified in the Appendix W to 40 C.F.R. Part 51 -
Guideline on Air Quality Models is inappropriate, the model may be changed or
another model substituted; such change or substitution shall be subject to
public comment and the written acceptance of the Department and the EPA
Regional Administrator or their designee. Methods such as those outlined in the
Protocol for Determining the Best Performing Model (EPA-454/R-92-025) and the
Interim Procedures for Evaluating Air Quality Models: Experience with
Implementation (EPA-450/4-85-006) should be used to determine the comparability
of air quality models.
B.
Renewal of a Part 70 License
(1) A previously submitted impact analysis
shall be acceptable unless:
(a) It has been
found to be deficient with respect to requirements set forth in subsection
14(A) of this Chapter;
(b) The
impact analysis fails to reflect available information with respect to ambient
air quality levels in the area, which, based upon the Department's expertise,
may reasonably be expected to be significantly impacted by the Part 70
source;
(c) The Part 70 source
emits a regulated pollutant for which an ambient air quality standard has been
adopted and whose impact was not addressed in the original impact analysis;
or
(d) There are changes in stack
or building configurations or other factors which are determined to
significantly alter the dispersion characteristics of the Part 70
source.
(2) Continuation
of an ambient air monitoring or meteorological monitoring program will be made
on a case-by-case basis at the time of the renewal. It is the burden of the
applicant to demonstrate the adequacy of existing data; its relationship to
past, present, and future facility operating conditions; and the adequacy of
other means to document continuing compliance.
(3) An existing Part 70 source is exempt from
an impact analysis with respect to a regulated pollutant whose allowable
emissions, after the application of control technology requirements specified
in Section 4 of this Chapter, do not exceed the following, unless the Part 70
source is located in or near a Class I area or an area where the available air
quality is limited, or other extenuating circumstances exist:
(a) 50 tons per year (tpy) for
SO2;
(b) 250
tpy for CO;
(c) 25 tpy for
PM10;
(d) 15
tpy for PM2.5 direct emissions;
(e) 50 tpy for NOx
(measured as NO2);
(f) 0.6 tpy for Lead (Pb); and
(g) 0.2 tpy of total Chromium.
C.
Modeling/Data
Collection Protocol. Any air quality dispersion modeling or data
collection program shall be developed consistent with the following
requirements:
(1)
Guidance. All
air quality dispersion modeling and meteorological data collection shall be
conducted consistent with Section 14 of this Chapter and Appendix W to 40
C.F.R. Part 51 - Guideline on Air Quality Models.
NOTE: For major sources and major modifications, the
applicant should consult with the Department and Federal Land Managers
(potentially affected federal lands are listed in Classification of Air Quality
Control Regions, 06-096 C.M.R. ch. 114) if Class I analyses are required, prior
to submitting a modeling/data collection protocol. The applicant is responsible
for obtaining the training necessary to perform the required air dispersion
modeling and meteorological data collection.
(2)
Variance from Guidance. Upon
an applicant's written request, the Department may grant a variance from any of
the requirements set forth in Section 14 of this Chapter and Appendix W to 40
C.F.R. Part 51 - Guideline on Air Quality Models, when the Department finds
that the alternative proposed by the applicant will not significantly affect
the accuracy of the modeling, or when data collection results or compliance
with the requirements specified in Section 14 of this Chapter and Appendix W to
40 CFR Part 51 - Guideline on Air Quality Models is technically infeasible or
economically unreasonable for the applicant. For any Part 70 source subject to
Prevention of Significant Deterioration (PSD) review, the variance shall be
subject to EPA review and written approval and shall be subject to notice and
opportunity for public comment pursuant to 40 C.F.R. Parts 51.160(f)(2) and
51.166 (l) (2).
(3)
Significant Impact Modeling Protocol for SO2,
NO2, CO, PM2.5, and
PM10. Prior to undertaking significant impact
modeling for SO2, NO2, CO,
PM2.5, and PM10, the applicant
shall provide in writing to the Department, a description of the following
factors that the applicant proposes to use in the significant impact modeling
demonstration (see Appendix W to 40 C.F.R. Part 51 - Guideline on Air Quality
Models for more specific guidance):
(a)
Operating scenarios, emissions units, and emission rates in English and metric
units;
(b) Regulated air
pollutants;
(c) Model(s) and
methodologies;
(d) Origin and
period of meteorological data, including location of collection site relative
to facility, meteorological parameters, instrument height, recovery rates,
substitution techniques, and quality assurance and quality control (QA/QC)
procedures;
(e) Receptor grid
(listing of coordinates and elevations, topographic maps covering the receptor
grid area map of receptors). A listing of all Digital Elevation Model (DEM)
quadrangles used and method(s) used to convert DEM data to the proposed
receptor grid shall also be included. If DEM data is being used to create a
rectangular receptor grid, then the elevation of each receptor point shall be
the highest elevation within the grid cell. The grid cell is defined as an area
enclosed by boundaries located half way to the nearest receptor in each
direction;
(f) Any special (e.g.,
fenceline, air intake, or flagpole) receptors;
(g) Identity of emissions units and emissions
which are included in baseline;
(h)
A properly scaled plot plan of the proposed facility with clearly marked true
north indicator, building heights, and an accurate scale ruler. Also, show the
location of the source on a map or aerial photograph of the area; and
NOTE: An original plot plan is preferred, but if a photocopy
is submitted, care should be taken to make sure that the scale is not changed
on any area of the plot.
(i) Building dimension and Good Engineering
Practice (GEP) analysis techniques. For each stack, all buildings that are
large enough and close enough to influence the stack should be considered in
the GEP analysis.
As expeditiously as possible and within 30 calendar days of
receipt of this information, the Department will notify the applicant in
writing that such information is complete and acceptable for modeling or notify
the applicant in writing of the reason(s) why the information is not complete.
If the information is not complete, the Department will clearly identify the
changes or additional information that must be submitted to complete the
protocol requirements.
(4)
Submittal of Significant Impact
Modeling(a) Prior to undertaking the
final air quality dispersion modeling demonstration, the applicant shall submit
the following for review:
(i) Significant
impact modeling results (If all modeled impacts of any regulated pollutant are
below the significant impact levels for all averaging periods, then no further
analysis is necessary for that pollutant);
(ii) Emissions data for regulated pollutants
not in the significant impact modeling protocol;
(iii) A preliminary analysis of nearby
sources that will not be included in the background concentration analysis;
NOTE: The Department is responsible for the final decision of
off-site sources to be modeled. The Department will provide the applicant with
a list of any additional sources that may have to be included in the final
modeling analysis and the requisite model input data for these sources. This
list will contain all data required for model input including source
location(s), emission rates, stack parameters, and necessary building
dimensions for the applicant to determine direction-specific building
parameters.
(iv)
Background Concentration Data. Conservative background values are
available from the Department for all areas of the state. Should the applicant
choose not to use the conservative background values supplied by the
Department, the applicant shall be responsible for determining background
values based on data normally supplied by and in consultation with the
Department. For sources needing more refined background values, general
guidance on determining background determinations based on monitoring data is
provided in the most recent version of the Department's Guideline Document for
Background Air Quality Determinations. Particular care must be taken when
determining background values so that they do not implicitly include any
impacts of the source(s) being modeled in order to avoid double counting;
and
(v)
Processed
Meteorological Data Base (if required by the Department). The use of
five consecutive years of off-site National Weather Service (NWS)
meteorological data (or other data equivalent or better in accuracy and detail
to the NWS data) or at least one year of site-specific data is the minimum
requirement for modeling applications. If more than one year (and up to five
years) of acceptable data is available, it shall be used in the air quality
analysis. If there is a gap in data from a catastrophic incident or a
persistent but subtle problem that evades detection, a two, three, four, or
five year on-site meteorological database acceptable for modeling purposes need
not be compiled from two, three, four, or five consecutive years or 24, 36, 48,
or 60 consecutive months of data. If this is the case, then the applicant shall
write to the Department requesting an exemption from the consecutive two,
three, four, or five year database requirement. If data requirements, source
configurations or characteristics of the surrounding area change, the database
may need to be updated after consultation with the Department. However, a
requirement to collect a new database will neither preclude the applicant's
ability to use the existing database in the interim data collection period nor
require the applicant to repeat any previously submitted analyses that used the
original database.
(b)
Within 30 calendar days of receipt of this information, the Department will
notify the applicant of the following in writing:
(i) The submitted information is complete and
acceptable for modeling or the reason(s) why the information is not complete or
acceptable. If the information is not complete or acceptable, the Department
will clearly identify the changes or additional information that must be
submitted to complete the protocol requirements; and
(ii) For each regulated pollutant for which
there are significant impacts, the Department will specify which operating
scenarios and other nearby sources, if any, needs to be further modeled.
If the applicant requests in writing, information in the
possession of the Department that is required for modeling (for example,
emissions which are included in baseline emissions, background data or other
emissions data from nearby sources), the Department will provide any available
information it has responsive to the request to the applicant within 30
calendar days.
(5)
Air Quality Dispersion Modeling
Protocol. If impacts from SO2,
NO2, CO, PM2.5, and
PM10 are above significance or if there are other
regulated pollutants to be modeled, then the applicant must provide in writing
to the Department, a description of the following factors (if different from
previously submitted data) that the applicant proposes to use in the air
quality dispersion modeling (see Appendix W to 40 C.F.R. Part 51 - Guideline on
Air Quality Models for more specific guidance):
(a) Operating scenarios, emissions units, and
emissions in English and metric units (including other nearby sources, if
necessary);
(b) Regulated air
pollutants;
(c) Model(s) and
methodologies;
(d) Origin and
period of meteorological data, including location of collection site relative
to facility, meteorological parameters, instrument height, recovery rates,
substitution techniques, and QA/QC procedures;
(e) Receptor grid (listing of coordinates and
elevations, topographic maps covering the receptor grid area, map of receptors
and, if applicable, a listing of all DEM quadrangles used and method(s) used to
convert DEM data to the proposed receptor grid). If DEM data is being used to
create a rectangular receptor grid, then the elevation of each receptor point
shall be the highest elevation within the grid cell. The grid cell is defined
as an area enclosed by boundaries located half way to the nearest receptor in
each direction;
(f) Any special
(e.g., fenceline, air intake, or flagpole) receptors;
(g) Identity of emissions which are included
in baseline emissions;
(h) A
properly scaled plot plan of the proposed facility with clearly marked true
north indicator, building heights and an accurate scale ruler. Also, show the
location of the source on a map of the area;
NOTE: An original plot plan is preferred, but if a photocopy
is submitted, care should be taken to make sure that the scale is not changed
on any area of the plot.
(i)
Building Dimension and Good
Engineering Practice Analysis Techniques. For each stack, all buildings
that are large enough and close enough to influence the stack should be
considered in the GEP analysis. Submit all building profile input program
(BPIP) input and output files on media approved by the Department. All tiers of
a building will be input as tiers and not as separate buildings; and
(j)
Background Concentration
Data
Within 30 calendar days of receipt of this information, the
Department will notify the applicant in writing that such information is
complete and acceptable for modeling or notify the applicant in writing of the
reason(s) why the information is not complete or acceptable. If the information
is not complete or acceptable, the Department will clearly identify the changes
or additional information that must be submitted to complete the protocol
requirements.
When all submitted information is considered complete and
acceptable for modeling, the applicant shall perform air quality dispersion
modeling and submit for review the air quality dispersion modeling analysis as
part of the final application submittal.
(6)
Presentation of Final
Results
Once compliance with ambient air quality standards, ambient
increments, and other limitations has been demonstrated through modeling, the
applicant shall prepare a written report documenting the source being modeled,
the modeling effort, and a compliance demonstration. The following information
is required in the written report and information required to be submitted on
media approved by the Department.
(a)
Introduction (briefly provide an overview of the project, the analyses
conducted, and the results);
(b)
Site and surroundings (describe the topography, demography, air quality control
region, and compliance status (attainment/nonattainment); include a topographic
map section showing the site and a properly scaled plot plan of the proposed
facility; include rural/urban classification and simple/complex terrain
determination, topography and land-use described in sufficient detail to
specify roughness length if roughness length is a required input for the
modeling system used in the analysis;
(c) Source description (provide an overview
of the source, describe the process(es) involved);
(d) Description of each emissions unit at the
source (describe the equipment/operations, emissions controls, emissions
limits; list emissions and stack parameters for each emissions unit in English
and metric units);
(e) Screening
modeling (describe the screening analyses performed):
(i) Modeling approach/model(s)
used;
(ii) Model version
used;
(iii) Model switch
selections;
(iv) Source data
(affected source and other nearby sources);
(v) Meteorological data;
(vi) Receptor data; and
(vii) Screening results.
(f) Final compliance modeling analysis,
(describe in detail modeling performed and results):
(i) Modeling approach/model(s)
used;
(ii) Model version
used;
(iii) Model switch
selections;
(iv) Source data
(affected source and other nearby sources);
(v) Meteorological data base. The
meteorological data base shall be submitted on media approved by the Department
if the applicant processed the meteorological data base;
(vi) Receptor data. A map of the receptor
grid shall be submitted. (If applicable, all DEM data used to create the
receptor grid shall be submitted on media approved by the Department);
and
(vii) Modeling results (all
input files needed to duplicate the final compliance model runs and all final
compliance model output and diagnostic files shall be submitted on media
approved by the Department).
(g) Compliance demonstration (describe how
the predicted concentrations comply with all applicable ambient air quality
standards and ambient increments):
(i)
Background determination (include table of values);
(ii) Compliance with ambient air quality
standards; and
(iii) Compliance
with Class II Prevention of Significant Deterioration (PSD) increments (if
applicable).
(h) Class I
area impact assessment, if required, (describe any analyses made for federal
Class I areas):
(i) Basis for
assessment;
(ii) Modeling
approach/model(s) used;
(iii) Model
version used;
(iv) Model switch
selections;
(v) Class I areas
affected;
(vi) Emissions and
conditions of operating scenarios;
(vii) Meteorological data;
(viii) Receptor grid;
(ix) Computational grid;
(x) Air quality impacts (ambient air quality
standards and ambient increments);
(xi) Visibility (plume blight assessment for
regions within a Class I area that are affected by plumes or layers that are
viewed against a background generally within 50 kilometers of the source) and
regional haze assessment (for regions of a Class I area where visibility
impairment from the source would cause a general alteration of the appearance
of the scene generally 50 kilometers or more away from the source or from the
interaction of the emissions from multiple sources) and other assessments that
the Federal Land Manager and the Department agree should be assessed;
and
(xii) All input files needed to
duplicate the final Class I analysis model runs and all final Class I analysis
model output and diagnostic files shall be submitted on media acceptable to the
Department.
NOTE: The Department recommends that any applicant likely to
be required to conduct and submit an air quality dispersion modeling analysis
meet at least once with Department staff prior to submitting the information
specified in subsection 14(C)(5) of this Chapter. A failure by the Department
to notify or provide information to the applicant as specified in this
subsection does not constitute an approval of the proposed protocol or
modeling.
