AWWA WQTC69383

The U. S. Environmental Protection Agency's (USEPA's) Office of Ground Water andDrinking Water Technical Support Center (TSC) has developed an update to the calculator fordetermining the quantitation level, known as the Lowest Concentration Minimum ReportingLevel (LCMRL). The LCMRL is a multi-concentration procedure where the lowest trueconcentration for which future recovery is predicted with high confidence (99%), to be between50 and 150% recovery. The procedure takes into account precision and accuracy at the sametime. It was implemented for the first time by TSC in conjunction with the second cycle of theUnregulated Contaminant Monitoring Rule and made available online by USEPA. Goals for therevised procedure included making it more robust and easier to use without creating an additionalburden on the laboratory community. This was accomplished by including a new variancemodel that covers all cases of variance and by incorporating nonlinear mean regression models.Although the new calculator is based on a more rigorous statistical approach, the user interfacehas been kept simple and user-friendly. The new approach handles a wider range of real worldsituations and met the improvement goals for the project. Includes 4 references, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

9

File Size:

1 file , 940 KB