Health Risk Limits Rules for Groundwater
SONARs

Below are Statements of Need and Reasonableness (SONARs) from previous years. Note: While SONARs contain information about why the guidance values were promulgated, they are written for a specific step in the rule development process. The SONAR will not show chemicals that were added or deleted during the rulemaking process and it does not reflect all information that was included in the final Health Risk Limit rule.

2016/2018 SONAR (PDF)
Provides information about HRLs adopted in 2018.

2014/2015 SONAR (PDF)
Provides information about HRLs adopted in November 2015.

2012/2013 SONAR (PDF)
Provides information about HRLs adopted in September 2013.

2010/2011 SONAR (PDF)
Provides information about HRLs adopted in March 2011.

2008/2009 SONAR (PDF)
This SONAR provides a thorough description of the scientific methods and principles used to develop HRLs, in addition to describing HRLs adopted in 2008/2009. For definitions of terms, see the Health-Based Water Guidance Glossary (PDF)

1993 SONAR (PDF)
Contains information about HRLs adopted in 1993 and 1994.