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New Source Review (NSR) Permitting

Ambient Air Definition/Interpretations

Date Title EPA Office Author
12/02/2019 Revised Policy on Exclusions from "Ambient Air" Administrator Wheeler, Andrew
05/23/1977 Applicability of PSD Increments Over Company Property OAQPS Barber, Walter
12/19/1980 Dec. 19, 1980 Ambient Air Letter Administrator Costle, Douglas
05/29/1987 UNAMAP 6 Dispersion Modeling with Building Wake Effects OAQPS

Tikvart, Joseph


Determining the Ambient Air Boundary for Potential Permit Application in Support of Alaska Industrial Development and Export Authority's Restart of Healy Clean Coal Project

Region 10 Helm, Nancy
03/01/1985 Applicability Determinations for Columbian Chemical Company CPDD Tyler, Darryl
10/17/1989 Ambient Air OAQPS Bauman, Robert
06/22/2007 Interpretation of "Ambient Air" in Situations Involving Leased Land Under the Regulations for Prevention of Significant Deterioration (PSD) OAQPS Page, Stephen
04/13/1992 Request For Further Clarification on EPA's Definition of "Ambient Air" OAQPS Seitz, John
08/01/2000 Interpretation of Ambient Air Region 7 Toensing, Don
01/09/2007 Ambient Air for Offshore Liquified Natural Gas Broadwater Project Region 2 Riva, Stephen
07/27/1987 Ambient Air Issue from New Jersey Department of Environmental Protection OAQPS Helms, G. Tom
09/21/1987 Ambient Air Definition OAQPS Helms, G. Tom

Related Topics: Prevention of Significant Deterioration (PSD) Increments | Significant Impact Levels (SILs) & Cumulative Analyses | Air Quality Monitoring

Return to Policy & Guidance Document Index

The “Relevant Guidance” index includes a collection of documents issued by EPA organized by topic area. These documents include memoranda, letters, orders, and other types of EPA actions that may provide guidance in one or more forms, such as an adjudication, statement of policy, interpretation of statutes or regulations, or technical information. Each collection is intended to be representative of EPA statements on the topic, but it may not be a complete listing of such statements. The collection does not reflect topic-specific statements that have been expressed by EPA though published rule preambles and Title V petition orders, nor does it include EAB decisions. Each document in the collection speaks for itself, and the inclusion or exclusion of a document in the collection is not intended by EPA to communicate anything more than what is expressed within each document. EPA makes no independent representations on this website as to the extent to which any document in the collection reflects EPA’s current views on the topic, is a final action by EPA, or has any legal effect or precedential weight. Readers are advised to review the documents in the collection and conduct their own assessment of such considerations based on the content of each document and other documents in the collection. Some of the information or views included in the documents may be affected by subsequent changes to the referenced statutory or regulatory language or by court decisions. In addition, many of the statements in these documents are based upon the federal regulations which may differ from rules that govern federally-approved programs. Permitting authorities are advised to consult with their EPA Regional Offices if there is a question as to the relevance of a particular statement to their NSR program.