Public water system record
Darlington Estates
On record as serving Rapid City, Pennington County, SD · Serves 25 people
Federal records show 3 health-based violations and no monitoring/reporting issues for Darlington Estates in the last ten years, including an unresolved Stage 1 Disinfection Byproducts Rule violation.
System profile
- Health-based violations, last 10 years
- 3
- Resolved
- 0
- Unresolved
- 1
- Archived by EPA
- 2
- Any acute record
- No
- Monitoring issues, last 10 years
- 0
Key facts
- Darlington Estates draws water from 1 well.
- Highest measured level in the last 10 years: Combined Radium (-226 and -228), 10 pCi/L, federal limit 5 pCi/L (2 times the limit), 2025.
Check whether Darlington Estates serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
| Contaminant | Rule family | Start date | Status | Acute |
|---|---|---|---|---|
|
Stage 1 Disinfection Byproducts Rule
Treatment technique failure
|
210 | Nov 12, 2025 | Active | No |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 10 pCi/L, federal limit 5 pCi/L (2 times the limit)
|
340 | Oct 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 7 pCi/L, federal limit 5 pCi/L (1.4 times the limit)
|
340 | Jul 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
What the violations mean
Combined Radium (-226 and -228)
2 incidentsTest results for Combined Radium (-226 and -228) were above the federal limit (a maximum contaminant level violation).
The utility had to notify customers about each of these violations.
Stage 1 Disinfection Byproducts Rule
1 incidentThe system did not meet a treatment requirement of the Stage 1 Disinfectants and Disinfection Byproducts Rule
Byproducts form when disinfectants react with natural material in water. Long-term exposure above federal limits may increase cancer risk
Where the water comes from
Darlington Estates draws water from 1 well.
Annual water quality report
Darlington Estates must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 500 or fewer people may meet the rule by telling customers the report is available on request, so you may need to ask Darlington Estates for a copy.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by South Dakota.
Certified drinking water labs by state EPA guidance for private wells