Geologists, engineers, chemists, regulatory officials, and environmental consultants often make important and expensive decisions based upon analytical results. In a contentious setting, the reliability of the laboratory data can be called into question and an independent, third-party assessment of the data then plays a pivotal role in defensibility. This third-party assessment is referred to as data validation. Scientists at the Center for Toxicology and Environmental Health, L.L.C. (CTEH^®) have a solid track record of performing data validation on projects that we sponsor. We strongly believe that the quality of the data validation process hinges on the scientific acumen of the individuals reviewing the data. For this reason, all individuals performing validation at CTEH^® are practicing laboratory scientists with field experience.

CTEH^® offers a wide range of data validation services depending on the project requirements. We perform validation of laboratory data packages or sample delivery groups pursuant to current U.S. EPA National Functional Guidelines, as well as U.S. EPA regional guidance documents, laboratory standard operating procedures, and various analytical methods. The National Function Guidelines provide a framework for data validation; however, detailed protocols have been promulgated only at the regional level to varying degrees. It is therefore critical that the individual performing validation maintain a thorough, working knowledge of pertinent regulations.

Levels of Data Assessment

Laboratory data packages can be reviewed on several levels depending on the project needs. CTEH^® uses a tiered approach with each tier building on the one below. A brief explanation of each tier is presented below:

Levels I and II are concerned with documenting the completeness of the data package, and are therefore more accurately referred to as data verification. In practice, Level II is generally the recommended starting point.

Level III begins the process of data validation and includes assessment of all results reported in the standard data package. Qualifiers are issued at Level III and above.

Level IV constitutes the most extensive and exhaustive review and actually computes results directly from the raw laboratory data itself. In principle, an independent report can be generated at this level and compared to the original laboratory findings as the ultimate in corroboration.