Radon:

U.S. EPA Publications on Radon
(http://www.epa.gov/iaq/radon/pubs/index.html)

U.S. EPA Indoor Air Quality Site
(http://www.epa.gov/radon/)

Septic Systems:

Septic System Information Website
(http://inspect-ny.com/septbook.htm)

Insects / Pests:

National Pest Control Association Web Site
(http://www.pestworld.org)

Water Quality:

EPA Advice on Lead in Drinking Water
(http://www.inspect-ny.com/water/leadwatr.html)

Drinking Water Testing Advice, published by Cornell University and the University of Maryland
(http://www.inspect-ny.com/water/watrtest.htm)

EPA Office of Water web site
(http://www.epa.gov/OW/)

USGS Water Resources of Maine web site
(http://me.water.usgs.gov/)

Mold:

EPA Indoor Air Quality: Mold information site
(http://www.epa.gov/mold/)