Groundwater Standards

Wisconsin's groundwater standards protect the groundwater from substances that affect human health or impact the water’s taste, color, and odor.

About two-thirds of Wisconsin residents use groundwater as their drinking water source.

Groundwater standards protect this resource by limiting the amount of harmful substances that can be discharged to groundwater in Wisconsin. The process for developing groundwater standards is specified in Wis. Stat. ch. 160 and involves several state agencies including the Department of Health Services (DHS), the Department of Natural Resources (DNR), and the Department of Agriculture, Trade, and Consumer Protection (DATCP).

The development of groundwater standards occurs in cycles and begins when state agencies identify substances that are or may be in Wisconsin’s groundwater. When a list of these substances is compiled, DNR requests that DHS recommend standards for the substances that are of public health concern. Once the recommendations are complete, DNR proposes rules to adopt the standards.

DHS is responsible for developing recommended public health standards.

Public health standards protect groundwater from substances pose a hazard to human health. For instance, the substance may increase the risk of illness, disease, or

death or may increase the risk or severity of a long-term disease. When requested, DHS follows a four-step process to develop the recommended standards, P-02816:

• Gather relevant scientific information.
• Select the appropriate standard based on requirements in State Statute.
• Document findings.
• Share recommendations.

For each substance of concern, DHS recommends a groundwater enforcement standard and a preventive action limit. The enforcement standard is the level used to establish limits for discharge to groundwater and the preventive action limit is the level used to trigger actions to prevent additional contamination.

There are several points where you can weigh in during the rule-making process.

When the recommendations are complete, DNR proposes rules to update or create new standards based on these recommendations.

Rulemaking is an extensive process and there are many internal steps that DNR and the Natural Resources Board must follow during a rulemaking effort.

Typically, the process takes about 31 months from initiation to effective date of rule revisions. During this time, there are several opportunities for the public to participate in the rulemaking process.