top of page
Data Verification, Data Validation

Data Verification and Validation


Our core chemistry consulting expertise revolves around understanding analytical chemistry, and its application in the fields of environmental and process chemistry.  As such, we provide unmatched analytical Data Verification, Data Usability, and Data Validation expertise that meets or exceeds regulatory and /or litigation support needs.  For more than 30 years, ATS has spent considerable resources developing, automating, and standardizing these capabilities.

Data Verification “…is the process of evaluating the completeness, correctness, and conformance/compliance of a specific data set against the method, procedural, or contractual requirements.”  Whereas, Data Validation “…is an analyte- and sample-specific process that extends the evaluation of data beyond method, procedural, or contractual compliance (i.e., data verification) to determine the analytical quality of a specific data set” (US EPA, 2002).

ATS provides data verification and validation services under a strict Quality Assurance (QA) and Quality Assurance (QA) program to ensure the end user of known and documented data quality.  Our experience on high profile projects over the past 30 plus years has provided ATS with the expertise and well established procedures to review and support all facets of the data review process.  Typical steps in our review process include:


The US EPA has guidance documents for environmental data verification and data validation which can be generally summarized by the following levels of data quality.  Data are reviewed according to ATS’s own documented review procedures that incorporate Data Quality Objectives/Quality Assurance Project Plan (DQO/QAPP) specific criteria with National Functional Guidelines.


Level I Data Validation:  Verification is made to confirm that analytical methods, analytes, and reporting levels are consistent with project objectives as well as applicable state and federal regulations.


Level II Data Validation:  In addition to a Level I data validation, these data are reviewed to verify that supporting QA/QC are of a level of quality necessary to support sample results.


Level III Data Validation: In addition to a Level I and II data validation, these data undergo a detailed review to ensure reported results have valid laboratory procedures and documentation underpinnings.  This includes all evaluations that are not derived exclusively from raw instrument data.


Level IV Data Validation: These data undergo full review and evaluation of a complete Data Validation Package (DVP) according to DQO/QAPP specific criteria, and National Functional Guidelines.  This level of review includes all summaries, and raw data associated with the data package, and ensures the highest level of defensibility.


Data Usability: These data have been subjected to data verification and Level IV validation, and are further reviewed across an entire project or sampling event.  The information presented in ATS Data Usability Reports provides the best summary of analytes present at a site from which risk assessment decisions can be made.



Contact ATS for competitive pricing and a custom quote.

Typical Steps In Our Review Process

Laboratory Data Review

(US EPA, 2002). US EPA Guidance on Environmental Data Verification and Data Validation (EPA QA/G-8), Office of Environmental Information, EPA/240/R-02/004.

bottom of page