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Review of the LT2 Rule


The 1996 Amendments to the Safe Drinking Water Act (SDWA) require EPA to review its existing national primary drinking water regulations no less often than every six years. A drinking water regulation revision must maintain or provide for greater protection of the health of persons.

EPA has completed regulatory review of the Long Term 2 Enhanced Surface Water Treatment Rule (LT2) in accordance with the Six-Year Review requirements. The LT2 rule review also complies with Executive Order 13563 Improving Regulation and Regulatory Review.

The LT2 review focused on the following rule provisions:
  • contaminant occurrence;
  • analytical methods; 
  • treatment to evaluate whether there are new or additional ways to manage risk; and
  • uncovered finished water reservoirs.

The Agency completed its review of the LT2 rule in 2016.

Public Meetings

As part of the LT2 regulatory review, EPA hosted the following public meetings:
  • December 7, 2011 - Discussed Cryptosporidium analytical methods and the source water monitoring data required by the LT2 rule.             Read more.
  • April 24, 2012 - Discussed information that may inform the regulatory review of the LT2 rule uncovered finished water reservoir requirement. Read more.
  • November 15, 2012 - Discussed the monitoring, binning and microbial toolbox information. Read more.