README for “Non-Attainment Areas 2004-Present” dataset. Office of Air Quality Planning and Standards (OAQPS), U.S. Environmental Protection Agency (EPA); U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS) [distributor] 2025-05-29 ---------------------------------------------------------------- LINKS TO DATASET ---------------------------------------------------------------- A. Dataset archive link: https://doi.org/10.21949/1520833 B. NTAD catalog dataset link (Current Year): https://geodata.bts.gov/search?q=NAA ---------------------------------------------------------------- SUMMARY OF DATASET ---------------------------------------------------------------- The Non-Attainment Areas 2004-Present dataset is from the U.S. Environmental Protection Agency (EPA), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’s (BTS's) National Transportation Atlas Database (NTAD). This dataset provides detailed information about areas identified in the U.S. where pollutant levels have not met the National Ambient Air Quality Standards (NAAQS) and have been designated "nonattainment areas (NAA)". These data are weekly from an OAQPS internal database. However, that does not necessarily mean the data have changed. For more information about these non-attainment areas, please see the website https://www.epa.gov/green-book/green-book-lead-2008-area-information. ---------------------------------------------------------------- TABLE OF CONTENTS ---------------------------------------------------------------- A. General Information B. Sharing/Access & Policies Information C. Data and Related File Overview D. Methodological Information E. Data-Specific Information for: Non-Attainment Areas 2004-Present [datasets] F. Update Log ---------------------------------------------------------------- A. GENERAL INFORMATION ---------------------------------------------------------------- 0. Title of Dataset: Non-Attainment Areas 2004-Present [dataset] 1. Description of Dataset: The Non-Attainment Areas 2004-Present dataset is from the U.S. Environmental Protection Agency (EPA), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’ (BTS's) National Transportation Atlas Database (NTAD). This dataset provides detailed information about areas identified in the U.S. where pollutant levels have not met the National Ambient Air Quality Standards (NAAQS) and have been designated "nonattainment areas (NAA)". These data are weekly from an OAQPS internal database. However, that does not necessarily mean the data have changed. For more information about these non-attainment areas, please see the website https://www.epa.gov/green-book/green-book-lead-2008-area-information. 2. Dataset archive link: https://doi.org/10.21949/1520833 3. Authorship Information: Principal Data Creator or Data Manager Contact Information Institution: Office of Air Quality Planning and Standards (OAQPS), U.S. Environmental Protection Agency (EPA) Address: 109 T.W. Alexander Drive, Research Triangle Park, NC 27709 Contact: Cakir.Halil@epa.gov Data Distributor Contact Information Name: National Transportation Atlas Database (NTAD) Institution: U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS), Office of Spatial Analysis and Visualization (OSAV) Address: 1200 New Jersey Ave. SE, Washington D.C. 20590 Email: ntad@dot.gov 4. Date of data collection and update interval: This dataset is updated every week. 5. Geographic location of data collection: United States of America 6. Information about funding sources that supported the collection of the data: U.S. Environmental Protection Agency (EPA), Office of Air Quality Planning and Standards (OAQPS) ---------------------------------------------------------------- B. SHARING/ACCESS & POLICIES INFORMATION ---------------------------------------------------------------- 0. Recommended citation for the data: U.S. Environmental Protection Agency (EPA), Office of Air Quality Planning and Standards (OAQPS); U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS) [distributor]. Non-Attainment Areas 2004-Present [datasets]. https://doi.org/10.21949/1520833. 1. Licenses/restrictions placed on the data: These data are in the Public Domain. 2. Was data derived from another source?: No. 3.This document was created to meet the requirements enumerated in the U.S. Department of Transportation's 'Plan to Increase Public Access to the Results of Federally-Funded Scientific Research' Version 1.1 << https://doi.org/10.21949/1520559 >> and guidelines suggested by the DOT Public Access website << https://doi.org/10.21949/1503647 >>, in effect and current as of December 03, 2020. ---------------------------------------------------------------- C. DATA & RELATED FILE OVERVIEW ---------------------------------------------------------------- 1. File List for the Non-Attainment Areas 2004-Present dataset A. Filename: Nonattainment_Areas_NTAD2004_Present.zip Short description: Compressed file folders containing the geospatial data for Non-Attainment Areas 2004-Present dataset. File folders are classified by NTAD publication year and data vintage year or date respectively. B. Filename: bts_NTAD_Nonattainment_Areas_DMP_20250529.pdf Short description: A PDF file containing the Data Management Plan that was created for current and future management of the data and associated files. C. Filename: bts_NTAD_Nonattainment_Areas_README_20250529.txt Short description: The README.txt file that includes human-readable information about the data, variable definitions, contact information, and other contextual information. The file you are reading now. 2. File List for the Nonattainment_Areas_NTAD2004_Present.zip collection. A. Filename: NTADXXXX_SHP_Final_NAA_XXXX*.zip or NTADXXXX_GDB_Final_NAA*.zip Short description: Compressed file folders containing the geospatial data for Non-Attainment Areas 2004-Present dataset. File folders are classified by NTAD publication year and data vintage year respectively. 3a. File List for the NTADXXXX_SHP_Final_Nonattainment_Areas_XXXX*.zip collection. A. Filename: naa_ma*.shp Short description: A shapefile containing the geospatial data for Non-Attainment Areas 2004-Present dataset. This includes associated files with extensions .prj, .dbf, .sbn, .sbx, .shx. B. Filename: naa_ma*.txt, naa_ma*.htm, and naa_ma*.shp.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, data dictionary, etc. 3b. File List for the NTADXXXX_GDB_Final_NAA*.zip collection A. Filename: NTADXXXX_GDB_Final_Nonattainment_Areas_XXXX*.gdb.zip Short description: A file geodatabase containing the geospatial data for Non-Attainment Areas 2004-Present dataset. Geodatabase (GDB) folders contain all the necessary components to view and otherwise interact with their data. B. Filename: Nonattainment*.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, etc. C. Filename: NAA*.xlsx Short description: Excel spreadsheet containing the dataset's data dictionary. ---------------------------------------------------------------- D. METHODOLOGICAL INFORMATION ---------------------------------------------------------------- 1. Description of methods used for collection/generation of data: A geographic area that meets or does better than the primary standard is called an attainment area; areas that don't meet the primary standard are called nonattainment areas. In some cases, a designated nonattainment area can include portions of 2, 3, or 4 states rather than falling entirely within a single state. Multi-state areas have had different state portions handled through up to 3 separate EPA regional offices. The actions of EPA and the state governments for separate portions of such areas are not always simultaneous. While some areas have had coordinated action from all related states on the same day, other areas (so-called "split areas") have had delays of several months, ranging up to more than 2 years, between different states. EPA must designate areas as meeting (attainment) or not meeting (nonattainment) the standard. A designation is the term EPA uses to describe the air quality in a given area for any of the six common air pollutants (criteria pollutants). After EPA establishes or revises a primary and/or secondary National Ambient Air Quality Standard (NAAQS), the Clean Air Act requires EPA to designate areas as “attainment” (meeting), “nonattainment” (not meeting), or “unclassifiable” (insufficient data) after monitoring data is collected by state, local and tribal governments. Once nonattainment designations take effect, the state and local governments have three years to develop implementation plans outlining how areas will attain and maintain the standards by reducing air pollutant emissions. 2. Instrument- or software-specific information needed to interpret the data: The data and documentation files can be opened with Esri ArcMap and any GIS software package. ---------------------------------------------------------------- E. DATA-SPECIFIC INFORMATION ---------------------------------------------------------------- 1. Non-Attainment Areas data table This dataset is updated every week. Dataset Manager is contacted to verify changes to data resulting in NTAD update. The metadata is updated in the same manner. For the most recent data, please visit the NTAD catalog at https://geodata.bts.gov/search?q=NAA A. Number of variables (columns): The data dictionary found in (PDF documentation) provides definitions for the variables B. Data Dictionary/Variable List: Because of the large number of variables, please refer to the Data Dictionary found within the file Nonattainment_Areas.txt for names, definitions, and formats of variables. C. Missing data codes: None ---------------------------------------------------------------- F. UPDATE LOG ---------------------------------------------------------------- This bts_Nonattainment_Areas_20250529_README.txt file was originally created on 2021-02-24 by Dominic Menegus, Geographer, dominic.menegus@dot.gov [Note changes or update to the readme.txt file, e.g.:] 2021-02-24: Original file created 2025-05-29: Revised document, including data descriptions and file organization.