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Water Quality Standard Revisions for Class 1 Waters
Minn. R. chs. 7050 & 7060
Douglas Hansen, Angela Preimesberger, and Laura SolemWilliam Cole, Carol Sinden, Paul Hoff, Katrina Kessler, Mark Tomasek
Minnesota’s Water StandardsMinn. R. chs. 7050 (and 7052)
Water Quality Standards encompass:
Meet Clean Water Act (CWA) requirements
1. Beneficial Use Classification for groundwater and surface waters
2. Numeric and Narrative Standards that protect those beneficial uses
3. Nondegradation Requirements to provide extra protection to
high quality waters
Beneficial Uses Seven classes in MN Rules:
1. Domestic Consumption (Drinking water)2. Aquatic life and recreation3. Industrial use and cooling4. Agricultural and wildlife use5. Aesthetics and navigation6. Other uses7. Limited resource value
Surface waters have multiple uses Existing, designated, both
Class 1-Domestic Consumption
Applied to all waters of the state that are or may be used as a source of supply for drinking, culinary or food processing use, or other domestic purposes and for which quality control is or may be necessary to protect the public health, safety, or welfare.
Purpose of Revision
Increase protection of domestic consumption of waters of the state.
Reasons for this Effort
1) Provide a better definition of drinking waters.2) Provide protection to waters for drinking water
purposes.3) Increase coordination with other rules and
statutes to enhance drinking water protection.
Revision Topics
Identify all waters to be used for DW must undergo treatment specified by MN Department of Health (MDH)
Disassociation of class 1 from class 2A (cold water) Incorporate language referencing the Groundwater Protection
Act (GWPA)o Use of health risk limits (HRLs) and health based values
(HBVs) Revision of class 1 subclass language Include language on Groundwater Contaminant Management
Zones Groundwater/Surface Water interaction
Approved Treatment
Suggested by 2011 Interagency GroupDrinking water standards apply to
waters in an untreated stateDoesn’t mean waters are to be used
without some form of approved treatment
Approved treatment must come from MDH
Class 1 & 2A Waters
Cold surface waters are designated as class 2A and class 1 suitable for drinking water purposes
Propose removing class 1 designation from class 2A waters that do not have an existing drinking water use
Class 2A waters with an existing drinking water use would be reclassified as 2Ad waters and would keep their class 1 designation
Use of HRLs & HBVs
Developed under authority given in the Groundwater Protection Act
Would be added as domestic consumption protection standards along with SDWA standards for all class 1 waters
Subclass Language
There are three subclasses to the class 1 designation Include language identifying HRLs and HBVs to be
used along with SDWA standards to protect waters Specifies the type of water treatment Incorporates language about aquifer sensitivity to
pollution using time of travel as an indicator
GW Contaminant Management Zones
Purpose is to protect the drinking water use of surrounding groundwater
The zone includes the plume of water being remediated
Management includes monitoring in and around the zone and public reporting of results
GW/SW Interaction
Addresses drinking water pollution from general aquifer recharge through surface infiltration by monitoring, treatment, and management of pollutant(s).
Direct influence of SW on GW Direct influence of GW on SW
