EP 1110-1-18
24 Apr 00
Subsurface Clearance. A proposed removal action may include a combination of these
alternatives.
(1) No DOD Action Indicated. This response action involves the continued use of the site
in its current condition. An NDAI may be appropriate if some removal action has already
occurred at the site or sector of the site or if the risk evaluation has determined that there is a very
low-level of safety risk.
(2) Institutional Controls. Institutional controls may be used either as a stand-alone
response action or as a supplement to other cleanup activities in order to address the residual risk
that remains at a site after a cleanup has been completed. Institutional controls are a response
action alternative used to restrict access to the site. Access can be restricted by imposing
administrative restrictions and/or by installing physical barriers. Administrative restrictions
could take the form of a deed restriction limiting the future use of the parcel or requiring that
precautions be taken during any future construction activities. Physical barriers may involve
fencing and posting the area to ensure that the local populace does not enter the property and
inadvertently come into contact with OE. Contact the OE MCX for additional information on
institutional controls.
(3) OE Surface Clearance. The OE surface clearance alternative includes the investigation
and removal of all potentially hazardous OE items to a depth of six inches. An OE surface
clearance alternative may be recommended for a site based on the nature and extent of the OE
contamination, the current and projected use of the site, and local community and regulatory
acceptance of the alternative. An OE surface clearance must be performed by UXO-qualified
personnel.
(4) OE Subsurface Clearance.
(a) The subsurface OE clearance alternative includes the investigation and removal of all
potentially hazardous OE items to a certain depth at a site. The depth of the OE clearance is
based on the nature and extent of the OE contamination, the current and projected use of the site,
and local community and regulatory acceptance of the proposed alternative. When there is
insufficient data to develop site-specific clearance depths, refer to DOD 6055.9-STD for
subsurface clearance default depth. However, it is more cost effective to develop site-specific
clearance depths based on current and future use of the site and the actual depth of OE found
during the EE/CA investigation.
(b) An OE subsurface clearance is typically conducted using geophysical instruments to
map the subsurface conditions and to determine the locations of anomalies that may be buried
OE items. Upon completion of the geophysical survey and an analysis of the data, UXO-
qualified personnel perform intrusive investigations to determine the nature of the geophysical
anomalies.
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