Model Clearinghouse Information Storage and Retrieval System
Record Details

Issue:

Ocean Wind 1, LLC, an affiliate of Orsted Wind Power North America, LLC, is 
developing an offshore wind energy project (“Ocean Wind Project”) in a 
federal lease area on the Outer Continental Shelf (OCS) approximately 24 km 
(15 miles) off the coast of New Jersey, near Atlantic City. The Ocean Wind 
Project will include up to 98 wind turbine generators and have an 
approximate production capacity of 1.1 gigawatts (GW). The Ocean Wind 
Project is subject to Prevention of Significant Deterioration (PSD) 
permitting and is required to submit an OCS air permit application that 
includes a dispersion modeling demonstration that air emissions from the 
Project will not cause or contribute to an exceedance of the National Ambient 
Air Quality Standards (NAAQS) or PSD increments

Ocean Wind 1, LLC has requested to use an alternative model, as provided in 
Section 3.2 of the Guideline on Air Quality Models (40 CFR Part 51, 
Appendix W), to conduct its PSD air quality modeling analysis of the Ocean 
Wind Project’s construction and operation and maintenance (O&M) activities. 
Specifically, Ocean Wind 1, LLC has requested to use the Coupled 
Ocean-Atmosphere Response Experiment (COARE) bulk flux algorithm, as 
implemented in the AERCOARE meteorological data preprocessor program, to 
prepare meteorological data for use in the American Meteorological Society/
Environmental Protection Agency Regulatory Model (AERMOD) dispersion program 
in lieu of the preferred Offshore and Coastal Dispersion (OCD) model to 
assess ambient impacts in a marine environment

EPA Region 2 has conducted a thorough review of Ocean Wind 1, LLCs request 
and has found the proposed application of the alternative model to be 
satisfactory and addresses the requirements of the Guideline, Section 
3.2.2(b), Condition (3), including the subsequent five elements contained in 
Section 3.2.2(e). As such, pursuant to the Guideline, Sections 3.0(b) and 
3.2.2(a), Region 2 currently intends to approve the use of proposed coupled 
AERCOARE-AERMOD alternative model approach for the Ocean Wind Project air 
permit application.

C/H Response:

The Model Clearinghouse concurs with EPA Region 2’s proposed approval of a 
coupled AERCOARE-AERMOD alternative modeling approach for the air quality 
modeling analysis required in the Ocean Wind Project based on the alternative 
model request package provided by Ocean Wind 1, LLC and the review 
documentation in the alternative model concurrence request memorandum 
provided by EPA Region 2. The Model Clearinghouse encourages EPA Region 2 to 
respond to Ocean Wind 1, LLC and to the docket for federal permitting actions 
related to the Ocean Wind Project with a letter of alternative model approval, 
as appropriate. The information associated with the EPA Region 2 alternative 
model approval and the Model Clearinghouse concurrence should be available for 
comment during the appropriate public comment period(s).

Given the possible importance of platform downwash and shoreline fumigation, 
the Model Clearinghouse continues to recommend caution and careful review 
before additional alternative model considerations of the coupled 
AERCOARE-AERMOD model methodology in other projects. This case-specific Model 
Clearinghouse concurrence does not constitute a generic approval of a coupled 
AERCOARE-AERMOD approach for other applications elsewhere. However, the scope 
of the technical assessment submitted here and with similar AERCOARE-AERMOD 
alternative model requests continue to provide a good basis for such 
considerations.

Memo:  Model Clearinghouse review of an alternative model application of AERCOARE 
in conjunction with AERMOD in Support of Outer Continental Shelf PSD air 
permitting of the Ocean Wind Project
        Dated: September 20, 2023
        From:  George Bridgers, Model Clearinghouse Director
                 Air Quality Modeling Group, Air Quality Assessment Division, 
                 Office of Air Quality Planning and Standards
        To:    Brian Marmo, Regional Air Quality Modeler
                 Permitting Section, Air Programs Branch, Air and Radiation Division
                 EPA Region 2, New York, New York
        Thru:  Richard Ruvo, Director
                 Air and Radiation Division
                 EPA Region 2, New York, New York
                 
Memo:  Concurrence Request for Approval of Alternative Model AERCOARE in Conjunction 
with AERMOD, in Support of Outer Continental Shelf PSD air permitting of the 
Ocean Wind 1 Offshore Wind Power Project
        Dated: August 29, 2023
        From:  Brian Marmo, Regional Air Quality Modeler
                 Permitting Section, Air Programs Branch, Air and Radiation Division
                 EPA Region 2, New York, New York
        Thru:  Richard Ruvo, Director
                 Air and Radiation Division
                 EPA Region 2, New York, New York
        To:    George Bridgers, Director of Model Clearinghouse
                 Air Quality Modeling Group, Air Quality Assessment 
                 Division,
                 Office of Air Quality Planning and Standards