When per- and polyfluoroalkyl substances (PFAS) contamination is allegedly found at or near a site, how can its origin be determined when there are so many possibilities? Is it from operations on the site, or is it coming from a nearby airport, fire-training station, manufacturing facility, landfill, incinerator, military base or even a neighboring farm due to the application of biosolids? These are important questions to ask because the sources of PFAS are more numerous than most people realize, and they are not always evident or obvious.
Environmental Standards has assembled a Multi-disciplinary Team of senior scientific experts including Quality Assurance (QA) Chemists, Groundwater Hydrologists, Geologists, and a Scientist with legal experience to research, develop a site-specific model, identify and “fingerprint” one or more of the PFAS sources. All key staff are experienced in litigation support including providing expert testimony and serving as fact witnesses.
Our Multi-disciplinary Team, typically led by QA Chemists, is experienced in performing historical research of site and nearby operations, employing sophisticated forensic techniques, and interpreting standard and sophisticated forensic data to fingerprint the source(s) of the apparent PFAS contamination. In determining a variety of site-specific approaches, Environmental Standards’ capabilities include:
- Reviewing historical data from the site and nearby operations
- Identifying additional site-specific compounds
- Comparing current PFAS signatures against known signatures from PFAS production processes
- Applying standard and more sophisticated targeted and non-targeted analysis
- Generating useful diagnostic ratios for evaluating trends, differences and similarities
- Utilizing innovative desktop software to evaluate laboratories’ raw analytical instrument data
- Applying routine and advanced statistical and spatial techniques for evaluating trends, differences and similarities
Statistical and Spatial Techniques
To derive a chemical signature, our staff may apply a variety of statistical and spatial techniques, including:
- Regression and Mixing Models
- Principal Component Analysis (PCA)
- Polytopic Vector Analysis (PVA)
- Positive Matrix Factorization
- Hierarchical and K-means Clustering
- Uncertainty Analysis
Seeing More Deeply
Environmental Standards employs specialized desktop software that provides access for deep dives into raw instrument files obtained from contracted laboratories from almost any gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC- MS/MS) instrument. This allows Environmental Standards senior-level Chemists to perform the most detailed fingerprinting possible and to identify non-target markers that indicate or rule out various contaminant sources. Analysis of the data includes several library resources integrated with the specialized software. Environmental Standards also holds proprietary libraries of chemical profiles for various product types and byproduct profiles, which are useful for identifying and discriminating among multiple possible PFAS sources.