HF5021

Purpose

• Update how compliance of subsurface sewage treatment systems is determined by requiring the use of “best evidence” of groundwater presence of sewage contaminants. The goal is to rely on recent, verifiable data to assess whether a system meets applicable requirements.

Main Provisions

• Adds a new subdivision (Subd. 14) to Minnesota Statutes 2024 section 115.55 establishing “best evidence of compliance.”
• Definition: Best evidence means results that are less than two years old from specific testing methods and sources, listed in priority order.
• Priority of evidence: If multiple sources exist, the order listed governs which data are given priority.
• Acceptable data sources (in order): 1) Groundwater contaminant measurements from a laboratory accredited by the Department of Health. 2) Continuous uncompressed probe-measured depth below the drain field base media to the groundwater table. 3) Data from the National Groundwater Monitoring Network, a watershed district, or historical depth-to-groundwater information from either source. 4) Empirical field measurements of depth to mottled soil. 5) Depth to mottled soil with redoximorphic features based on Munsell soil color charts.
• Accessibility of data: The agency, local units of government, or inspectors must accept results less than two years old from any of these methods when the property owner or lessee offers to submit the results.
• Notification rights: Property owners/lessees must be notified of their rights under this subdivision at least 90 days before a notice of noncompliance is issued.

Significant Changes to Existing Law

• Replaces a stricter or singular approach to proving subsurface sewage treatment system compliance with a broader, standardized framework for “best evidence.”
• Expands acceptable sources of evidence beyond direct site testing to include groundwater networks, watershed district data, and soil-based indicators, all with a clear two-year recency requirement.
• Introduces a formal process for owners/lessees to submit existing data from multiple sources and requires advance rights notification before enforcement actions for noncompliance.

How this would be Applied

• When evaluating ISTS compliance, agencies and inspectors would prioritize the listed data sources and rely on the most recent data (under two years old).
• Owners/lessees may proactively submit applicable data to support compliance determinations.
• Authorities must provide at least 90 days’ notice detailing rights before issuing a noncompliance finding.

Relevant Terms - subsurface sewage treatment system (ISTS) - best evidence of compliance - groundwater contaminants - Department of Health - two years (recency) - continuous uncompressed probe - depth below drain field base media to groundwater - National Groundwater Monitoring Network - watershed district - historical depth-to-groundwater information - depth to mottled soil - redoximorphic features - Munsell soil color charts - noncompliance - owner or lessee - rights under this subdivision