EPA provides access to environmental data through the following: 

• Environmental Dataset Gateway (EDG)
• Geospatial Applications
• Registry of EPA Applications, Models, and Data Warehouses (READ)
• System of Registries (SoR)

Accessing the above links will lead to each catalog's main page. From there, specific data sets can be queried by subject area, environmental issue, or file type. Data sets can be downloaded and used by the public.