yy West Lake Update
November 20,2014	-I*
EPA Policy on Temporary and Perma-
nent Relocations at Superfund Sites
NOTE: Because of recent questions from community mem-
bers on the topic, this issue of West Lake Update takes a
closer look at EPA's policy regarding temporary and perma-
nent relocations associated with Superfund sites.
The National Contin-
gency Plan (NCP) includes
a reference to temporary
or permanent relocation of
residents, businesses, and
community facilities as a
possible method of rem-
edying releases when the
Agency determines that it is
necessary to protect human
health and the environment. Because permanent relocation
is considered a remedial activity, from a legal perspective
EPA would typically consider and select it only pursuant to
the remedy evaluation process set forth in the Comprehen-
sive Environmental Response, Compensation, and Liability
Act (CERCLA) and the NCP It is also the preference of
the Agency to keep communities intact by not permanently
relocating families and businesses whenever possible.
In the history of the Superfund program, EPA has imple-
mented permanent relocations ofbusinesses or residences
at only 33 of the more than 1,600 final and deleted sites
on the National Priorities List. Of those 33, the majority
were for engineering solutions necessary to implement the
cleanup remedy.
At the vast majority of Superfund sites, EPA's remedial ac-
tions address site risks to enable families and businesses to
remain in their communities, making permanent relocation
unnecessary. EPA guidance clearly states that while reloca-
tion authority is provided for by CERCLA, the preference
to keep communities in place during a cleanup is consistent
with Superfund statutory and regulatory requirements. In
the rare instances where permanent relocation does occur,
the primary reasons for doing so are to address an immedi-
ate risk to human health (where an engineering solution
is not readily available) or where site structures (such as
homes and businesses) are an impediment to implementing
a protective cleanup.
Region 7 s response actions, to date, at the West Lake
Landfill Superfund Site make temporary or permanent
relocation inconsistent with EPA's authority and practice as
well as with the scientific evidence. While EPA understands
the public's concern about the subsurface smoldering event
(SSE), at this time EPA does not believe that data substanti-
ates a conclusion that the SSE is moving toward the radio-
logically-impacted material (RIM).
Even if the SSE were to contact the RIM, EPA does not
believe it would become reactive or explosive at the temper-
atures that are typically observed in an SSE. An SSE in Op-
erable Unit 1, with or without contact with the RIM, would
be expected to change the conditions within the landfill,
and likely would increase the rate at which landfill gases
are released through surface cracks or fissures. These gases
could be released as steam, radon and potentially other
gases (as determined by the composition of the non-RIM
materials present). However, based on EPA's understanding
of SSEs, the release of any gases would likely be localized,
and not occur over the entire site. EPA does not anticipate
there would be RIM in gases or associated with the fine
particulates if gases were to be released from the Westlake
Landfill due to an SSE. EPA is working with the Missouri
Department of Natural Resources (MDNR) to collect ad-
ditional information on temperatures, gases and subsidence
that can be used to develop a better picture of trends and
potential movement of the SSE.
Meanwhile, EPA is evaluating the construction of an
isolation barrier that will serve to prevent an SSE from con-
tacting the RIM. Decisions about the construction and lo-
cation of an isolation barrier will be made in consideration
of all response actions being evaluated for the site, to ensure
that this interim action is complementary to the remedial
action that EPA will ultimately perform. EPA will evaluate
any issues related to the SSE ana isolation barrier that may
impact the integrity of the remedial action.
Available scientific data indicates that people living near
and working outside the boundaries of tne site are not
being exposed to contaminants released from the site at
levels of concern. In 2013, EPA's scientific aerial survey of
the site and nearby residential and commercial/industrial
properties detected no off-site excess gamma emissions in
surface soil. The same survey only detected gamma emis-
sions from surface soil in one small area of Operable Unit 1,
Area 2, which was previously identified by EPA's Remedial
Investigation. Also in 2013, off-site groundwater sampling
by the U.S. Geological Survey and EPA of privately-owned
wells northwest and southwest of the site detected no
radionuclide exceedances of drinking water standards. In
2005, MDNR conducted soil sampling along St. Charles
Rock Road, Boenker Road and Taussig Road, just beyond
the site's boundaries, and did not detect uranium, thorium,
or radium above the cleanup standards established for the
FUSRAP sites. In addition, EPA's 2014 sampling at the
Bridgeton Municipal Athletic Complex found no exceed-
ances for uranium, thorium, or radium.
Region 7 continues to work diligently towards a final rem-
edy at the site. As stated above, the primary reasons for in-
cluding permanent relocation as part of a site's final remedy
would be to address an immediate risk to human health, or
where site structures are an impediment to implementing a
protective cleanup. Due to the current site conditions (no
off-site exposure to contaminants above a level of concern
and no existing structures preventing the implementation
of a final remedy), at this time Region 7 does not believe
site data warrants consideration of permanent relocation.
EPA will continue to evaluate all data related to the site,
and will consider all appropriate remedial alternatives as
required by CERCLA.
For more information about relocation and the Superfund
program, please visit: www.epa.gov/superfund/community/
Community Inquiries
Ben Washburn
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