New RSLs Have Arrived!
Biannually, typically in May and November, the United States Environmental Protection Agency (US EPA) updates their Regional Screening...
EPA Adds Select PFAS Chemicals to CERCLA Hazardous Substances List
The United States Environmental Protection Agency (US EPA) has designated two widely used polyfluoroalkyl substance (PFAS) chemicals as...
Happy Valentine’s Day! It’s Official - New ASTM E1527-21 Phase I ESA Standard Adopted!
Prepared by Managing Principal Mark Shifflett and Supervising Environmental Scientist Heather Fields As of February 14, 2024, the most...
All I Want for Christmas...
To say that this year has been challenging is probably the most overused statement of the year. Given we are entering the holiday season,...
Preliminary DTSC Study on Attenuation Factors
Prepared by Brianne Archer, P.E. and Jeffrey Dagdigian, PhD Vapor intrusion occurs when chemical vapors migrate from contaminated...
Indoor Vapor Intrusion from Underlying Groundwater Contamination
Brianne Archer, Supervising Engineer, PE, CPP Richard Vogl, Principal Hydrogeologist, CHG, CEG, PG TECH MEMO: How do you know if...
Mitigation Measures for Vapor Intrusion
What options are available to mitigate the risks posed by potential vapor intrusion?
TCE and PCE Indoor Air Regulatory Levels - A Deeper Dive
Let’s talk about the indoor air screening levels for trichloroethene (TCE) and perchloroethene (PCE). This discussion might be useful for...
COVID-19 Postpones Deadline for Submission of Comments Supplemental Guidance for Vapor Intrusion
Supplemental Guidance for Screening and Evaluating Vapor Intrusion - Draft for Public Comments (Draft Supplemental VIG)
Cleaning and Reusing Face Masks and Other Protective Face Coverings
Cleaning and Reusing Face Masks and Other Protective Face Coverings
