Industrial Vapor Intrusion
Client: US Department of Defense
A Department of Defense facility in San Diego, California covering 172,000 square feet presented a persistent challenge: despite years of investigation and mitigation efforts, TCE vapor intrusion continued problematically at the site.
VaporSafe® deployed monitoring for one week. The team observed dramatic increases in concentrations in the late morning. Analysis revealed the pattern correlated with barometric pressure drops and increased pressure differentials between subsurface and indoor environments.
Upward vapor flow can be caused by drops in barometric pressure and increases in pressure differential. This has significant implications with respect to conventional monitoring methods, which can miss these episodic events entirely.
Continuous monitoring uncovers concentration spikes driven by barometric pressure that single-grab samples can miss.