Proposed NR 140 Groundwater Standards for Pesticides
DATCP’s Role with Groundwater Protection
State law (Wis. Stat. § 160) outlines the groundwater monitoring responsibilities of state agencies. The statute requires that regulatory agencies communicate with the Wisconsin Department of Natural Resources (DNR) and Wisconsin Department of Health Services (DHS) to identify when substances are detected in groundwater that exceed an existing enforcement standard or preventative action limit, or when compounds are detected that do not have existing state or federal standards. To meet these responsibilities, DATCP collects groundwater samples from private drinking wells, monitoring wells, and irrigation wells located within agricultural areas. DATCP analyzes these samples for more than 100 pesticide compounds plus nitrate through its lab. DATCP provided DNR with a list of pesticides to consider for new groundwater standards in a letter dated February 16, 2026. DNR began the rulemaking process to establish groundwater standards for several pesticides, and DATCP will aid DNR with this process.
For
questions about proposed standards for pesticides included in administrative
rule NR 140, email datcpgw@wisconsin.gov.