Guidance Documents Vapor
Vapor Intrusion Pathway
The Department is currently evaluating provisions of N.J.A.C. 7:26E-2.1(c)3 and the Vapor Intrusion Technical
Guidance (Version 3) as it relates to the analysis of naphthalene and 2-methylnaphthalene for vapor intrusion (VI)
samples. As detailed in the Department guidance document "Department Implementation Strategy for Revised Vapor
Intrusion Screening Levels" (available at
the Department does not require the analysis of naphthalene and 2-methylnaphthalene as part of a VI investigation over the next five (5) months.
Based on a continuing review of scientific information, the Department is modifying two existing provisions as follows:
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 will update other posted web documents by the end of this week to reflect this change.
In addition to Method TO-17, the Department is developing provisions for analyzing naphthalene using either Method TO-15
or Low Level TO-15. The announcement on the revised methodology should be released next month. Starting on July 16, 2013,
sampling and analysis for naphthalene, consistent with N.J.A.C. 7:26E-2.1(c)3, will be required. The modified TO-15 methodologies
should be available at that time.
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.
It is recommended that the user periodically refer to the NJDEP Vapor Intrusion web site for the latest
information on the vapor intrusion pathway.
Most Recent Updates:
Vapor Intrusion Technical Information
Additional Vapor Intrusion Information
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