Biannually, typically in May and November, the United States Environmental Protection Agency (US EPA) updates their Regional Screening...

The United States Environmental Protection Agency (US EPA) has designated two widely used polyfluoroalkyl substance (PFAS) chemicals as...

Prepared by Managing Principal Mark Shifflett and Supervising Environmental Scientist Heather Fields As of February 14, 2024, the most...

To say that this year has been challenging is probably the most overused statement of the year. Given we are entering the holiday season,...

Prepared by Brianne Archer, P.E. and Jeffrey Dagdigian, PhD Vapor intrusion occurs when chemical vapors migrate from contaminated...

Brianne Archer, Supervising Engineer, PE, CPP Richard Vogl, Principal Hydrogeologist, CHG, CEG, PG TECH MEMO: How do you know if...

What options are available to mitigate the risks posed by potential vapor intrusion?

Let’s talk about the indoor air screening levels for trichloroethene (TCE) and perchloroethene (PCE). This discussion might be useful for managing vapor intrusion issues at a dry-cleaning site and related strip mall or a commercial/industrial site that historically used solvents for cleaning and degreasing. The concepts presented herein are useful for any volatile organic compound (VOC) that can lead to issues with indoor air vapor intrusion. Indoor Air and Soil Gas Screenin

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