Wisconsin
Hazardous substance spills
Spills of hazardous substances in Wisconsin are reported to the Wisconsin Department of Natural Resources (DNR), whose Remediation and Redevelopment (RR) Program oversees the response through a Spill Team of regional spill coordinators and others. DNR treats a spill as a release of one or more hazardous substances into the environment, usually recent and acutely risky, that calls for an immediate response and report. Its idea of a hazardous substance is broad: petroleum products, agricultural and industrial chemicals, wastewater and manure can all qualify. The reporting duty is in Wis. Stat. ยง 292.11 and ch. NR 706, Wis. Adm. Code.
In a Phase I ESA
ASTM E1527-21 does not name state spill lists among its standard record sources. The federal counterpart of a state spill list is the emergency response record described on the ERNS page. A Wisconsin spill report still matters, because it can be the only state record of a release that never became a cleanup case. Four Wisconsin details shape the search.
- Contamination found by sampling must be reported too. DNR says a discharge has to be reported when lab results for soil, sediment, vapor, indoor air or water reveal it, and its own example is a Phase II assessment that finds contaminated soil and groundwater. The report goes in at once on Form 4400-225, DNR's non-emergency Notification for Hazardous Substance Discharge Form, through the RR Submittal Portal, or by phone to a DNR regional office, without waiting for a written report, with a summary of the lab data.
- Small spills may never be reported. DNR lists spills it generally does not need to hear about: under 1 gallon of gasoline; under 5 gallons of any other petroleum product; any amount of gasoline or other petroleum fully contained on an impervious surface; discharges a permit or approved program allows; under 25 gallons of liquid fertilizer or 250 pounds of dry fertilizer; certain small pesticide releases; spills held in secondary containment and recovered with no discharge to the environment; and amounts below the federal reportable quantity. Ask about small releases at the interview as well as searching the records.
- A quick cleanup may leave no map point. In DNR's tracking database (BRRTS), spills are their own activity type, numbered from 04, and DNR says they are usually cleaned up fast. The RR Sites Map leaves out spills that were contained or cleaned up at once with no cleanup case opened. Search BRRTS for spill activities rather than relying on the map.
- Reporting does not create liability. DNR says reporting a spill or other discharge does not make the reporter liable, and it encourages everyone to report known discharges.
Who must report, and when
DNR says whoever causes a spill must tell DNR at once, as soon as the spill is found, and should not wait for lab results if the discharge can be confirmed by sight or smell. If that person does not report it, the owner or controller of the property where it happened must. A spill is reportable when it affects or may affect health or the environment, causes a fire, explosion or safety hazard, is not cleaned up right away, or exceeds the exemptions above. The responsible party must contain and clean up the spill, dispose of the waste properly, and document the work and send DNR what the law requires.
When the responsible party is unavailable or unwilling to act in an emergency, DNR may call in a zone contractor and seek repayment from the responsible party afterward. A spill may also need a federal report to the National Response Center, at 800-424-8802, under EPCRA or CERCLA, DNR's page says.
Where to look a site up
- BRRTS on the Web can limit a search to spill activities. See BRRTS.
- DNR's spills page links a page it labels Open Spill Incidents, described on DNR's database page as open incidents under investigation and evaluation. This handbook did not open it.
- Spills are reported to DNR's 24-hour toll-free hotline, 1-800-943-0003. Regional spill coordinators are on DNR's RR Program staff contacts page.
Getting the file
The spill pages read give no route of their own for a spill file. The BRRTS page sends you to the DNR staff member named on an active activity's details page, and to an RR program specialist for a closed one. DNR prefers records requests by email, to DNRRecordsResponse@wisconsin.gov, and accepts them in any format; see Public Records Request.
Sources
Wisconsin Department of Natural Resources pages, read October 13, 2026, no modified date shown: