You can search the Laws of the US Federal Code (USC) Database by keyword or code title and section using this website: http://uscode.house.gov/ (e.g. Title 42, Chapter 15B or 42 USC Ch. 15B).
The US Government provides a searchable and browseable version of the Code of Federal Regulations (CFR). You may browse the various parts of 40 CFR, Protection of the Environment, on this website (a shortened URL is provided here): http://bit.ly/YB231c
There is also a library database that provides the above functions and access to additional information. It is listed below.
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