EPA data as of Oct 2026 · page updated 2026-10-29

Rib Mountain Water Utility

Rib Mountain Water Utility (EPA ID WI7370660) in Wausau, WI supplies groundwater (wells) to about 6,398 people: no health-based violations since 2016, latest lead result 2.4 ppb, PFAS 9.4 ppt.

Service area

EPA service-area boundary (state-supplied or EPA-modeled)
Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

System facts

People served6,398
Connections2,416
Sourcegroundwater (wells)
WholesalerNo

Health-based violations

No health-based violations reported since 2016.

Lead

Jun 20232.4 ppb
Jul 20203.5 ppb
Jun 20176.1 ppb
Jun 20145.7 ppb
Jun 20113.4 ppb
Jan 20085.4 ppb
Jan 20055.8 ppb
Jan 20026.4 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

CompoundHighest resultSamples with detectionEPA limit
PFPeA23 ppt2 of 8—
PFBA16 ppt3 of 8—
PFOS9.4 ppt4 of 84 ppt MCL
PFHxS9.2 ppt3 of 8—
PFHxA5.9 ppt2 of 8—
PFOA5.2 ppt2 of 84 ppt MCL
PFBS3.8 ppt3 of 8—
PFDAnot detected0 of 8—
PFNAnot detected0 of 8—
PFHpAnot detected0 of 8—
HFPO-DA (GenX)not detected0 of 8—

EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), samples 2023–2025; ppt = parts per trillion (ng/L). The 4.0 ppt maximum contaminant levels for PFOA and PFOS were set by EPA in 2024; water systems have until the end of the decade to comply.

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has Rib Mountain Water Utility had drinking water violations?

No health-based violations reported since 2016.

What is the lead level in Rib Mountain Water Utility water?

The latest 90th-percentile lead result (Jun 2023) was 2.4 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does Rib Mountain Water Utility have PFAS in its water?

Highest PFOA or PFOS result in EPA’s 2023–2025 testing was at or above 4.0 ppt, EPA’s 2024 maximum contaminant level for each. 7 PFAS compounds detected.