This report presents the results and conclusions from the ambient air monitoring conducted as part of the 2010 National Monitoring Programs (NATTS, UATMP, and CSATAM) - three individual programs with different goals, but together result in a better understanding and appreciation of the nature and extent of toxic air pollution. The 2010 NMP includes data from samples collected at 52 monitoring sites that collected 24-hour air samples, typically on a 1-in-6 or 1-in-12 day schedule. Twenty-four sites sampled for 61 volatile organic compounds (VOC); 30 sites sampled for 14 carbonyl compounds; nine sites sampled for 80 speciated nonmethane organic compounds (SNMOC); 26 sites sampled for 22 polycyclic aromatic hydrocarbons (PAH); 14 sites sampled for 11 metals; and 23 sites sampled for hexavalent chromium. Over 214,900 ambient air concentrations were measured during the 2010 NMP. This report uses various graphical, numerical, and statistical analyses to put the vast amount of ambient air monitoring data collected into perspective. Not surprisingly, the ambient air concentrations measured during the program varied significantly from city-to-city and from season-to-season.

Final report. Contract Number: EP-D-09-048 "Delivery orders 2,6,7,8,9, 10 & 11"--Beneath title Two CD-ROMs (one 508 complaint, one not 508 complaint) in Adobe format are located in front binder pockets of documents. Includes bibliographical references.

Volume 1. Main -- Volume 2. Appendices.