Clean Water Act (CWA) Section 405(d)(2)(C) requires EPA to review federal biosolids (sewage sludge) standards every two years to identify additional toxic pollutants that occur in biosolids and set regulations for those pollutants if sufficient scientific evidence shows they may harm human health or the environment. The biennial review process is intended to fulfil the CWA requirement to identify additional pollutants that occur in biosolids.

Biennial Reviews:

• Biennial Review of 40 CFR Part 503(7): 2016 – 2017 and Fact Sheet
• Biennial Review of 40 CFR Part 503(6): 2015 and Fact Sheet
• Biennial Review of 40 CFR Part 503(5): 2013 and Fact Sheet
• Biennial Review of 40 CFR Part 503(4): 2011 and Fact Sheet
• Biennial Review of 40 CFR Part 503(3): 2009
• Biennial Review of 40 CFR Part 503(2): 2007
• Biennial Review of 40 CFR Part 503(1): 2005