At U.S. Water, ensuring the integrity of analytical testing is a cornerstone of our operational excellence. For specialized testing that falls outside the scope of on-site capabilities, we partner with certified third-party laboratories such as GEL Laboratories, Pace Analytical, Eurofins Scientific, and others. These labs provide crucial data, but interpreting those results—and catching errors—requires active involvement from our expert team.
The Importance of Oversight
It’s important to understand that contract laboratories simply report test results—they do not evaluate whether results are reasonable based on historical trends, site-specific expectations, or permit requirements. That’s where U.S. Water’s operational oversight becomes essential. Our experienced operators and technical staff review every data point to ensure that the results are accurate and actionable.
Even certified laboratories can encounter challenges like equipment malfunctions, data entry errors, or sample handling issues. Below are real examples that demonstrate the importance of careful observation of results:
- Incorrect Detection Limit Reporting: A sample for 2,4,6-Trichlorophenol was inadvertently diluted, causing the detection limit to exceed the regulatory threshold. A resample was required to meet compliance.
- Unexpected Permit Exceedance: A weekly effluent test for COD came back above the permit limit, despite historical non-detects. A retest confirmed the result was incorrect and the final report was amended.
- Sample Mislabeling: Influent and effluent samples for PFOS were mislabeled, resulting in reversed values. The lab acknowledged and corrected the error.
- Inconsistent Data: A test showed an unusually high COD result with a corresponding non-detect for DOC—a relationship that typically trends together. With no ability to retest due to limited sample volume, a second sample was collected and confirmed normal levels.
Proactive Practices for Reliable Results
Because laboratory turnaround times and sample holding times can be limiting factors (e.g., BOD samples must be tested within 48 hours), our team always schedules compliance samples early in the sampling window. This gives us time to review, question anomalies, and retest if needed—minimizing risk and maintaining compliance.
If your facility receives unusual or unexpected laboratory results, please contact your U.S. Water project team immediately. Our Technical Support staff is always available to assist in interpreting results, communicating with labs, and navigating regulatory reporting requirements. Your compliance is our commitment. We’re here to ensure data quality, every step of the way.
