Environmental Forensics and Complex Data Analysis
Environmental Standards, Inc. personnel perform and oversee the collection, evaluation, storage and retrieval, data interpretation, and statistical analysis of large-scale environmental data sets. Our senior forensic chemists and data managers/data analysts work in concert to condense complex analyses into manageable, discrete tasks. Our forensic and data teams routinely manage and evaluate environmental data sets involving tens of thousands of samples and millions of records. The requirements for data interpretation and data quality oversight in chemical forensics applications differ significantly from those needed in regulatory and remediation focused applications. The ability to compare, integrate, and analyze data sets requires understanding which data are truly signals and which are statistical noise. Environmental Standards has in-depth knowledge and experience in assessing sampling, laboratory, and analytical method reliability (for internal and external data interpreters), so we can manage down the data set, focus the statistical evaluations, and help avoid wasted effort. In addition to assessing and managing sample data, Environmental Standards provides robust capabilities in data interpretation.
Key Experience and Skills
- Statistical, chemical “unmixing,” using regression mixing models, positive matrix factorization, PCA, and multivariate techniques.
- Calculating diagnostic ratios, creating and evaluating double ratio plots.
- Tracking changes that occur to chemical mixtures during release, weathering, and transport, and evaluating and using data types that measure these effects.
- Using a variety of accelerated aging methods.
- Calculating transport vectors and mechanisms (hydrogeology, fractionation, diffusion), and uncertainty analysis.
- Analyzing and validating data and auditing laboratories for pertinent analyte types, (e.g., alkylated PAHs, geochemical biomarkers, PIANO analytes, homologs, fractional and compound specific stable isotopes[13C/12C, 2H/1H, 37Cl/35Cl, 18O/16O, and 17O/16O,36Cl/C]).
- Discriminating chemical profiles between:
- Hydrocarbons of petrogenic and phytogenic origin.
- Biogenic vs. thermogenic methanes.
- Differing plumes of chlorinated solvents.
- Differing sources of PCBs, dioxins and other organohalogens.
- Differing stages of weathering, and changes in exposure and toxicity over time.
- Stable and unstable “diagnostic” ratios (PAHs, PCBs, dioxins, and other chemical classes).
- Differing geochemical biomarkers (hopanes, steranes, and triaromatic steroids).