Vapor Intrusion Pathway
The presence of volatile chemicals in contaminated soil or ground water offers the potential for chemical
vapors to migrate through subsurface soils and/or preferential pathways (such as underground utilities)
thereby impacting the indoor air quality of area buildings. Vapor intrusion refers to this migration of
volatile chemicals from the subsurface into overlying buildings. The Vapor Intrusion information linked
from this page represent specific guidance developed by the Department to assist in the investigation
of the vapor intrusion pathway at contaminated sites.
The Vapor Intrusion Technical Guidance Version 4.1, Posted January 2018
It is recommended that the user periodically refer to the NJDEP Vapor Intrusion web site for the latest
information on the vapor intrusion pathway.
Vapor Intrusion Technical Information and Updates:
Analysis of naphthalene and 2-methylnaphthalene for vapor intrusion samples
The Department completed its evaluation of the provisions
of N.J.A.C. 7:26E-2.1(c)3 and the Vapor Intrusion Technical
Guidance (Version 3.1) as it relates to the analysis of
naphthalene and 2-methylnaphthalene for vapor intrusion
(VI) samples. Based on a continuing review of scientific
information, effective July 16, 2013, the Department is
requiring the following:
The analysis for 2-methylnaphthalene will not
be required for VI samples collected during the investigation
of kerosene, jet fuel, diesel fuel, fuel oil No. 2, and
heavier petroleum products. The Department intends to update
the Technical Requirements for Site Remediation to remove
the requirement to analyze VI samples for 2-methylnaphthalene.
Until the rule is updated, persons responsible can apply
a variance pursuant to N.J.A.C. 7:26E-1.7 to not perform
this analysis. The Department has already updated other
posted web documents to reflect this change.
Naphthalene analysis will be required for VI samples
collected during the investigation of kerosene, jet fuel,
diesel fuel, fuel oil No. 2, and heavier petroleum products.
In addition to USEPA Method TO-17, the Department will also
allow the use of USEPA Method TO-15, NJDEP Method Low Level
TO-15 and USEPA Method TO-13 A. Any laboratory performing
the methods must have the applicable laboratory certifications
and must have a demonstrated reporting limit of less than
or equal to 3 ug/m3 consistent with N.J.A.C. 7:26E-2.1(a)3.
Additional Vapor Intrusion Information
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