After being taken to task by states and its own Inspector
General for lack of final guidance on Vapor Intrusion, EPA has just
released draft guidance documents for hazardous substances
and petroleum products for comment. The guidance documents are
already generating discussion on the blogosphere, with comments due
to EPA by May 24th. Below are some of the issues EPA will have to
address for its guidance for hazardous substances, and those of us
addressing vapor intrusion for our clients.
Will the guidance collapse under its own weight? EPA's
recommended framework relies upon collecting and evaluating
multiple lines of evidence to support risk management decisions,
detailed investigation of vapor intrusion including rigorous data
quality objectives and recognition of seasonal/temporal variability
in levels, consideration of options for building mitigation and
subsurface remediation, decisions on how institutional controls can
be crafted and monitored, and how the public will be involved. The
practical question is how much evidence and process is enough for a
rational decision, and how costly and time-consuming an evaluation
effort is justified? Rarely are actions taken quickly in the CERCLA
or RCRA world, but if there are risks, then they should be acted
upon, and applying the guidance in other contexts will be
challenging. There already appears to be a consensus that EPA's
approach will be costly, and give vapor intrusion a life of its own
in remedial decision-making. EPA will have to address this issue,
or find its guidance bypassed or ignored, given the need for timely
decisions.
Should we all buy stock in fan manufacturers and makers of
synthetic vapor barriers? EPA offers (only on page 125 of 143)
the question of weighing relative costs of characterization vs.
engineered exposure controls. If EPA guidance is followed, the cost
of implementing the guidance will at times greatly exceed the cost
of engineering controls. Clients want the deal "done" and
are not likely to wait for a lengthy deliberative process.
What role will EPA acknowledge for OSHA standards? EPA
proposes guidance for residential and non-residential buildings,
but as a practical daily matter, there are separate standards and
approaches for workplace and non-workplace scenarios. EPA
doesn't directly address that issue in the 2013 guidance, even
though the Agency had helpful statements in its 2002 proposal. The
issue gets even more complicated given the unsurprising obligation
to consider potential future land uses. If the default scenario is
residential use, will the workplace vs. non-workplace distinction
disappear?
Déjà vu all over again? Yogi Berra may have
been commenting on repeats of the Mickey Mantle/Roger Maris
back-to-back home runs, but it is pretty clear we will be reopening
sites that may have had vapor intrusion issues, and assessing old
sites at which the issue was never raised, or addressed following
different procedures. EPA settled the question in November 2012 for
CERCLA five-year reviews by declaring vapor intrusion a mandatory
topic, and plans to adopt final Hazard Ranking System amendments
for vapor intrusion. The guidance document applies to RCRA sites as
well, but EPA knows that the guidance will surely find application
at many types of sites where volatile chemicals may have been
present. Although the document is limited to CERCLA/RCRA guidance,
its general purpose is to be helpful, and EPA should probably
re-emphasize that not only are all sites different, the recommended
framework may not even be practical when applied through other
state programs. At risk of over-generalizing, practitioners have
learned to recognize the advantages of not following
CERCLA and RCRA approaches.
EPA will receive many comments, and there is some cleanup work to
be done on the guidance documents, but look for the final documents
to be completed in months, not years.
Thanks to Jeff Carnahan, LPG, EnviroForensics, for sharing with me
his expertise on vapor intrusion. However, the thoughts expressed
here are solely mine.
This alert originally appeared on the American College of Environmental Lawyers' (ACOEL) blog.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.