LSRP Corner: Vapor Intrusion Technical Guidance

Synergy Environmental, Inc.
Dennis Libenson, LSRP

February 14, 2018

The NJDEP released Version 4.1 of the Vapor Intrusion Technical Guidance in January 2018. This version included a significant clarification to the discussion of petroleum hydrocarbons (PHC).

The NJDEP noted in Version 4 of the Vapor Intrusion Technical Guidance that gasoline additives such as oxygenates or lead scavengers are not considered as PHC. Going further, NJDEP now explicitly states the following in the most recent version:

“Gasoline additives, such as oxygenates (e.g., methyl tert butyl ether) and lead scavengers (e.g., ethylene bromide [EDB] and 1,2-dichloroethane), are not considered PHCs. As such, these gasoline additives must utilize the 100-foot investigative trigger distances associated with non-PHC compounds.”  The trigger distance for PHC compounds is 30 feet.

One key trigger for further investigation is the applicable Groundwater Screening Level. As a reminder, the current Groundwater Screening Levels are 580 ppb for MTBE; 0.4 ppb for ethylene dibromide, and 3 ppb for 1,2-dichloroethane.

The NJDEP Webpage for Vapor Intrusion Technical Guidance is:

Feel free to contact Synergy at

Mr. Libenson is an LSRP in Synergy Environmental’s Cherry Hill, NJ Office.He can be reached via e-mail at

Print Friendly, PDF & Email