Public water system record

Knoll Enterprises

Serves an area of San Bernardino County, CA · 500 people served

Federal records show 69 health-based violations and 10 monitoring/reporting issues for Knoll Enterprises in the last ten years, including an unresolved LEAD AND COPPER RULE REVISIONS violation.

CA3600504
LUDLOW
CA
500 served

System profile

Source water Groundwater

ZIP 92338

EPA system ID CA3600504

Verify this system on EPA ECHO →

Health-based violations, last 10 years: 69
Resolved: 0
Unresolved: 1
Archived by EPA: 68
Any acute record: No
Monitoring issues, last 10 years: 10

Key facts

Knoll Enterprises draws water from 3 wells (1 of them for emergency, seasonal or other part-time use).
Highest measured level in the last 10 years: Arsenic, 0.048 mg/L, federal limit 0.01 mg/L (4.8 times the limit), 2018.
Most recent formal enforcement: compliance order (no penalty) by California, February 2025.
Record on file since 2011, with 15 health-based violations before October 19, 2016.

Check whether Knoll Enterprises serves your address

Health-based violations

Since October 2016

Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.

Contaminant	Rule family	Start date	Status	Acute
Arsenic Contaminant limit exceeded Measured 0.0248 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Oct 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0245 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Jul 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.026 mg/L, federal limit 0.01 mg/L (2.6 times the limit)	330	Apr 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0258 mg/L, federal limit 0.01 mg/L (2.6 times the limit)	330	Jan 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
LEAD AND COPPER RULE REVISIONS Treatment technique failure	350	Oct 17, 2024	Active	No
Arsenic Contaminant limit exceeded Measured 0.0246 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Oct 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0248 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Jul 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0245 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Apr 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0244 mg/L, federal limit 0.01 mg/L (2.4 times the limit)	330	Jan 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0309 mg/L, federal limit 0.01 mg/L (3.1 times the limit)	330	Oct 1, 2023	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0318 mg/L, federal limit 0.01 mg/L (3.2 times the limit)	330	Jul 1, 2023	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0317 mg/L, federal limit 0.01 mg/L (3.2 times the limit)	330	Apr 1, 2023	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0317 mg/L, federal limit 0.01 mg/L (3.2 times the limit)	330	Jan 1, 2023	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0315 mg/L, federal limit 0.01 mg/L (3.2 times the limit)	330	Oct 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0314 mg/L, federal limit 0.01 mg/L (3.1 times the limit)	330	Jul 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0312 mg/L, federal limit 0.01 mg/L (3.1 times the limit)	330	Apr 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.031 mg/L, federal limit 0.01 mg/L (3.1 times the limit)	330	Jan 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)	330	Oct 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	330	Jul 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	330	Apr 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.029 mg/L, federal limit 0.01 mg/L (2.9 times the limit)	330	Jan 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2021	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.028 mg/L, federal limit 0.01 mg/L (2.8 times the limit)	330	Oct 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.025 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Jul 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.025 mg/L, federal limit 0.01 mg/L (2.5 times the limit)	330	Apr 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0273 mg/L, federal limit 0.01 mg/L (2.7 times the limit)	330	Jan 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0355 mg/L, federal limit 0.01 mg/L (3.6 times the limit)	330	Oct 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0397 mg/L, federal limit 0.01 mg/L (4 times the limit)	330	Jul 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.041 mg/L, federal limit 0.01 mg/L (4.1 times the limit)	330	Apr 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.041 mg/L, federal limit 0.01 mg/L (4.1 times the limit)	330	Jan 1, 2019	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.048 mg/L, federal limit 0.01 mg/L (4.8 times the limit)	330	Oct 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)	330	Jul 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.017 mg/L, federal limit 0.01 mg/L (1.7 times the limit)	330	Apr 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.016 mg/L, federal limit 0.01 mg/L (1.6 times the limit)	330	Jan 1, 2018	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)	330	Oct 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jul 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)	330	Jul 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Apr 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.022 mg/L, federal limit 0.01 mg/L (2.2 times the limit)	330	Apr 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Jan 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0235 mg/L, federal limit 0.01 mg/L (2.4 times the limit)	330	Jan 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Combined Uranium Contaminant limit exceeded	340	Oct 1, 2016	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No
Arsenic Contaminant limit exceeded Measured 0.0333 mg/L, federal limit 0.01 mg/L (3.3 times the limit)	330	Oct 1, 2016	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.	No

Monitoring and reporting issues

Since October 2016

Missed tests or reports, not contaminants found above a limit.

Issue	Start date	Status
Public Notice OTHER	Dec 31, 2025	Active
Nitrate Monitoring and reporting	Jan 1, 2025	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
LEAD AND COPPER RULE REVISIONS RPT	Oct 17, 2024	Active
Nitrate Monitoring and reporting	Jan 1, 2024	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Nitrite Monitoring and reporting	Jan 1, 2023	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Consumer Confidence Rule OTHER	Jul 1, 2022	Resolved
Nitrite Monitoring and reporting	Jan 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Nitrate Monitoring and reporting	Jan 1, 2022	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Nitrite Monitoring and reporting	Jan 1, 2020	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Revised Total Coliform Rule Monitoring violation	Jan 1, 2020	Resolved

Full record since 2011

EPA's records for Knoll Enterprises go back to 2011. Before October 19, 2016 they list 15 health-based violations (2 resolved, 13 archived by EPA without a recorded fix) and 13 monitoring or reporting violations.

Violations that began in	Health-based	Monitoring and reporting
2010 to October 18, 2016	15	13
October 19, 2016 to 2019	24	0
2020s	43	10

Most recent health-based violation before October 19, 2016: Combined Uranium, began October 2016, Archived.

Show all 15 health-based violations before October 19, 2016

Contaminant	Start date	Status
Combined Uranium Contaminant limit exceeded	Oct 1, 2016	Archived
Arsenic Contaminant limit exceeded Measured 0.0333 mg/L, federal limit 0.01 mg/L (3.3 times the limit)	Oct 1, 2016	Archived
Combined Uranium Contaminant limit exceeded	Jul 1, 2016	Archived
Arsenic Contaminant limit exceeded Measured 0.0298 mg/L, federal limit 0.01 mg/L (3 times the limit)	Jul 1, 2016	Archived
Combined Uranium Contaminant limit exceeded	Apr 1, 2016	Archived
Arsenic Contaminant limit exceeded Measured 0.0283 mg/L, federal limit 0.01 mg/L (2.8 times the limit)	Apr 1, 2016	Archived
Arsenic Contaminant limit exceeded Measured 0.0328 mg/L, federal limit 0.01 mg/L (3.3 times the limit)	Jan 1, 2016	Archived
Combined Uranium Contaminant limit exceeded	Jan 1, 2016	Archived
Combined Uranium Contaminant limit exceeded	Apr 1, 2015	Archived
Arsenic Contaminant limit exceeded Measured 0.0325 mg/L, federal limit 0.01 mg/L (3.3 times the limit)	Apr 1, 2015	Archived
Combined Uranium Contaminant limit exceeded	Jul 1, 2014	Archived
Arsenic Contaminant limit exceeded Measured 0.036 mg/L, federal limit 0.01 mg/L (3.6 times the limit)	Jul 1, 2014	Archived
Arsenic Contaminant limit exceeded Measured 37.3 µg/L, federal limit 10 µg/L (3.7 times the limit)	Jul 1, 2013	Resolved
Arsenic Contaminant limit exceeded Measured 40.5 µg/L, federal limit 10 µg/L (4.1 times the limit)	Jan 1, 2013	Resolved
Arsenic Contaminant limit exceeded Measured 38 µg/L, federal limit 10 µg/L (3.8 times the limit)	Jan 1, 2011	Archived

Enforcement actions

California regulators took 11 formal enforcement actions against Knoll Enterprises between 2012 and 2025, filed as 12 records in EPA's data. The most recent was a compliance order (no penalty) in February 2025.

Date	By	Action	Violations covered
Feb 20, 2025	California	Compliance order (no penalty)	1 violation: Nitrate
Feb 19, 2025	California	Compliance order (no penalty)	1 violation: Nitrite
Feb 9, 2023	California	Compliance order (no penalty)	2 violations: Nitrite, Nitrate
Oct 27, 2022	California	Compliance order (no penalty)	1 violation: Consumer Confidence Rule
Mar 31, 2020	California	Compliance order (no penalty)	1 violation: Revised Total Coliform Rule
Mar 6, 2020	California	Administrative penalty	4 violations (4 health-based): Combined Uranium, Arsenic
May 24, 2017	California	Administrative penalty	60 violations (60 health-based): Arsenic, Combined Uranium
Mar 9, 2017	California	Compliance order (no penalty)	2 violations (2 health-based): Combined Uranium, Arsenic
Oct 11, 2013	California	Compliance order (no penalty)	15 violations (13 health-based): Arsenic, Combined Uranium, Fluoride
Jan 8, 2013	California	Compliance order (no penalty)	12 violations (1 health-based): Fluoride, Arsenic, Combined Uranium
Aug 28, 2012	California	Compliance order (no penalty)	1 violation (1 health-based): Arsenic

What the violations mean

Arsenic

37 incidents

Arsenic exceeded the federal limit

Long-term arsenic exposure is linked to cancer and cardiovascular effects

Combined Uranium

31 incidents

Test results for Combined Uranium were above the federal limit (a maximum contaminant level violation).

The utility had to notify customers about each of these violations.

LEAD AND COPPER RULE REVISIONS

1 incident

The system did not complete a treatment step or action that the LEAD AND COPPER RULE REVISIONS requires (a treatment technique violation).

The utility had to notify customers about this violation.

Where the water comes from

Knoll Enterprises draws water from 3 wells (1 of them for emergency, seasonal or other part-time use).

Annual water quality report

Knoll Enterprises 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 Knoll Enterprises 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 California.

Certified drinking water labs by state EPA guidance for private wells