Record-only indicator: C
Not a safety rating. Missing or old measurements can produce a high score.
Coverage: 2/2 mapped systems have a dated lead result; 0/2 have copper results; 2/2 have UCMR monitoring.
| Contaminant | Reported value or bound | Historical comparison value | Interpretation | Status |
|---|---|---|---|---|
| Lead |
0.564 ppbPeriod end: 12/31/2024
|
15 ppb | Largest reported value or bound among mapped systems; not necessarily the largest actual concentration. | At/below comparison value |
UCMR5 occurrence results are screening information, not a finding of regulatory compliance or noncompliance. PFAS rules and compliance dates are evolving.
| Compound | Level | EPA MCL | Interpretation | Status |
|---|---|---|---|---|
| PFBA | 7.5 ppt | No standard | 500 ppt | No federal MCL shown |
| PFPeA | 3.8 ppt | No standard | — | No federal MCL shown |
| PFHpA | 3.4 ppt | No standard | — | No federal MCL shown |
| PFHxA | 3.3 ppt | No standard | 400 ppt | No federal MCL shown |
Public-record summary
Record-only indicator — incomplete or old records can produce a high score. A score of 100 is not a safety finding. Coverage: 2/2 mapped systems have a dated lead result; 0/2 have copper results; 2/2 have UCMR monitoring. Tap water quality in Duncan, Oklahoma (73534) receives an record-only indicator of C (Mixed record-based signals) with a score of 55 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 40 points below the Oklahoma state average of 95. The area is served by 2 water systems providing water to approximately 23,000 people, using surface water sources. PFAS testing detected 4 compounds, all below the EPA final MCL values used for comparison. Over the past 5 years, water systems here have accumulated 20 violations, including 7 health-based violations.
Grade C summarizes the records available to this model, not household safety. Missing, bounded or old measurements can produce a high score, including 100. Review coverage, dates and the current utility report before interpreting this indicator.
Health Information
Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.
Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.
Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.
If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.
Common Questions
The record-only indicator is C (55/100). It cannot determine whether your tap water is safe. Missing, bounded or old measurements can produce a high score. Check the coverage and sampling dates below and your utility's current notices.
ZIP code 73534 is served by 2 water systems using surface water sources, providing water to approximately 23,000 people. Surface water systems are more susceptible to contamination from agricultural runoff, industrial discharge, and weather events, but typically undergo more extensive treatment including filtration and disinfection.
The largest reported lead value or bound is 0.564 ppb, for the sampling period ending 12/31/2024. This is a system-level 90th-percentile record, not a measurement at your tap. Compare the sampling date and original utility report before interpreting it.
4 PFAS compounds were detected in water serving Duncan, Oklahoma, with no result above the individual comparison values shown here; some compounds have no individual federal MCL. This comparison is informational: federal compliance timelines and the status of some PFAS standards are still evolving. Activated carbon or reverse osmosis filters can reduce some PFAS when appropriately certified and maintained.
Water systems serving Duncan, Oklahoma have received 20 violations in the last 5 years, including 7 health-based violations. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.
This public-record indicator cannot select household treatment. Confirm your supplier, current utility report and tap-testing results first; match any treatment to a certified contaminant-reduction claim and follow its maintenance instructions.