Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2025. This website is no longer updated and links to external websites and some internal pages may not work. More information »
This information is provided for technical experts who intend to work directly with the database. Other users can retrieve information using the PCS Search.
The PCS tables in Envirofacts are organized into the subject areas shown below. Click on a subject area to view the tables.
