The level of analysis shall depend upon the size of the 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 shall include 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 listed under "significant emissions increase" in 06-096 CMR 100. The analysis shall be conducted in accordance with the provisions of subsection 7(E) of this Chapter, Prohibited Dispersion Techniques, 06-096 CMR 116 and Appendix W to 40 CFR Part 51 - Guideline on Air Quality Models.
Air quality modeling conducted as part of the licensing of a new source or modification in the United States is substantially governed by the Appendix W to 40 CFR 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, and to complete modeling, as approved, and submit results within six (6) 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 6 months after approval of the protocol and modeling results must be submitted within six (6) 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.
A Major source or Major Modification shall be exempt from the requirements of this subsection if its emissions do not significantly impact a Class I area or an area where the increment is known to be violated or substantially consumed, and
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 06-096 CMR 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.
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.
As expeditiously as possible and within thirty (30) calendar days of receipt of this information, the Department shall 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 shall clearly identify the changes or additional information that must be submitted to complete the protocol requirements.
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.
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 shall attempt to provide such information to the applicant within thirty (30) calendar days.
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.
Within thirty (30) calendar days of receipt of this information, the Department shall 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 shall 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.
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 outline indicates the information required in the written report and information required to be submitted on media approved by the Department.
NOTE: The Department recommends that any applicant likely to be required to conduct and submit an air quality dispersion modeling analysis meet once with the Department staff prior to submitting the information specified in subsection 7(E)(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 and/or modeling.
NOTE: If a source of NOx is subject to both the Prevention of Significant Deterioration (PSD) and New Source Review (NSR) thresholds, the source shall comply with the nonattainment area NSR provisions for ozone as well as modeling requirements for the NO2 National Ambient Air Quality Standard, NO2 increment, and Class I areas analyses, etc.
06- 096 C.M.R. ch. 115, § 7