Science & Technology

Competency and Proficiency Testing

Field Branches Quality System and Technical Procedures

Regional Streamflow Duration Assessment Methods

Regional SDAMs for the United States classify streams as perennial, intermittent, or ephemeral at the stream reach scale. Learn about SDAMs, their development, and how to apply these field methods using the web application

Design and Installation of Monitoring Wells

Economic and Cost Analysis for Air Pollution Regulations

This web area provides technical tools, databases and models that have been developed for cost, benefit, and economic impact analyses of EPA air pollution regulations.

Previous AP-42 Versions, Supplements and Updates

AP-42, Compilation of Air Pollutant Emission Factors Volume I, Stationary Point and Area Sources. This page links to older versions of Volume I and is available for historic purposes.

2016 Version 3 Technical Support Document

This TSD describes how the emission inventories were prepared for air quality modeling by the U.S. Environmental Protection Agency (EPA) for criteria air pollutants to represent the years of 2016, 2023 and 2028.

Draft Risk Evaluation for Butyl Benzyl Phthalate (1,2-Benzene- dicarboxylic acid, 1- butyl 2(phenylmethyl) ester) (BBP)

EPA designated o-dichlorobenzene as a high priority chemical in December 2019 and the chemical is currently undergoing risk evaluation.

Draft Risk Evaluation for Diisobutyl Phthalate (1,2-Benzene- dicarboxylic acid, 1,2- bis-(2methylpropyl) ester) (DIBP)

EPA designated di-isobutyl phthalate - (1,2-Benzene- dicarboxylic acid, 1,2- bis-(2methylpropyl) ester) as a high priority chemical in December 2019 and the chemical is currently undergoing risk evaluation.

Draft Risk Evaluation for Dibutyl Phthalate (1,2-Benzene- dicarboxylic acid, 1,2- dibutyl ester) (DBP)

EPA designated dibutyl phthalate (1,2-Benzene- dicarboxylic acid, 1,2- dibutyl ester) as a high priority chemical in December 2019 and the chemical is currently undergoing risk evaluation.

Draft Risk Evaluation for Di-ethylhexyl phthalate - (1,2-Benzene- dicarboxylic acid, 1,2- bis(2-ethylhexyl) ester) (DEHP)

EPA designated di-ethylhexyl phthalate - (1,2-Benzene- dicarboxylic acid, 1,2- bis(2-ethylhexyl) ester) as a high priority chemical in December 2019 and the chemical is currently undergoing risk evaluation.

Additional Coral Reef Resources

Coral reefs are among the most biologically diverse and valuable ecosystems on Earth. This web site describes the importance of coral reefs, threats to them, and ongoing efforts to protect them.

EPA Research about Coral Reefs

Coral reefs are among the most biologically diverse and valuable ecosystems on Earth. This web site describes the importance of coral reefs, threats to them, and ongoing efforts to protect them.

Top Management Challenges for EPA and CSB

Top Management Challenges Reports issued by the Office of Inspector General

Report: U.S. Chemical Safety and Hazard Investigation Board Fiscal Years 2024 and 2023 Financial Statement Audit Controls

U.S. Chemical Safety and Hazard Investigation Board Fiscal Years 2024 and 2023 Financial Statement Audit