CORRESPONDENCE_1993 - 1996 - Laserfiche WebLink

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v STANDARD PROVISIONS AND REPORTING REQUIREMENTS September 1993 FOR WASTE DISCHARGE REQUIREMENTS FOR DISCHARGES REGULATED BY CHAPTER 15 AND/OR PART 258 -9- 5. MDLs and PQLs shall be derived by the laboratory for each analytical procedure, according to State of California laboratory accreditation procedures. These MDLs and PQLs shall reflect the detection and quantitation capabilities of the specific analytical procedure and equipment used by the lab, rather than simply being quoted from USEPA analytical method manuals. In relatively interference -free water, laboratory -derived MDLs and PQLs are expected to closely agree with published USEPA MDLs and PQLs. If the lab suspects that, due to a change in matrix or other effects, the true detection limit or quantitation limit for a particular analytical run differs significantly from the laboratory - derived MDL/PQL values, the results shall be flagged accordingly, along with estimates of the detection limit and quantitation limit actually achieved. The MDL shall always be calculated such that it represents a concentration associated with a 99% reliability of a non -zero result. The PQL shall always be calculated such that it represents the lowest constituent concentration at which a numerical value can be assigned with reasonable certainty that it represents the constituent's actual concentration in the sample. Normally, PQLs should be set equal to the concentration of the lowest standard used to calibrate the analytical procedure. 6. All QA/QC data shall be reported, along with the sample results to which they apply, including the method, equipment, and analytical detection and quantitation limits, the percent recovery, an explanation for any recovery that is less than 80%, the results of equipment and method blanks, the results of spiked and surrogate samples, the frequency of quality control analysis, and the name and qualifications of the person(s) performing the analyses. Sample results shall be reported unadjusted for blank results or spike recoveries. In cases where contaminants are detected in QA/QC samples (i.e., field, trip, or lab blanks), the accompanying sample results shall be appropriately flagged. 7. Unknown chromatographic peaks shall be reported, along with an estimate of the concentration of the unknown analyte. When unknown peaks are encountered, second column or second method confirmation procedures shall be performed to attempt to identify and more accurately quantify the unknown analyte. Analysis of Monitoring Data Unless an alternate method has been approved by the Executive Officer, the Discharger shall use one of the following methods, according to the method selection procedure below— One-Way Parametric Analysis of Variance (ANOVA), One -Way Non -Parametric ANOVA (Kruskal-Wallis Test), Method of Proportions, or non -statistical method —to compare the downgradient concentration of each monitored constituent or parameter with its respective background concentration to determine if there has been a release from the WMU.