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 utility alignments are better known. The general requirements for soils
mechanics and foundation engineering are described in NAVFAC Design Manuals
DM-5, DM-7, and DM-21 series or the latest Military Handbooks pertaining to
this subject.
6.2.1 Subsurface Investigation: Prior to commencing subsurface
investigations in the field, the A-E shall locate previous soil reports,
boring logs, pile driving records, existing utilities, underground
structures in Plan Files and/or in the PWC where project is located. The
PDE will indicate the location/project which may contain useful
information. However, it shall be the A-E's responsibility to locate and
review all pertinent reports and information.
a. Historical and Archaeological Resources. In the event borings are
required in an area where surface elements of historic properties may be
affected, review of the project and archaeological monitoring by
PACNAVFACENGCOM archaeologists will be required.
b. Take borings and samples with appropriate care, perform required
laboratory testing, visually inspect the site, perform engineering
analyses, and prepare a written report of the findings and recommendations.
Perform soil borings within the footprints of structures whenever possible.
The number of borings and their depth shall be sufficient to obtain data
for selection of foundation systems and design criteria and the character
of materials to be encountered in the construction. Consider such factors
as: area geology; historical data relating to site development and seismic
events; any unusual precipitation characteristics; surface and subsurface
soil and bedrock conditions; groundwater conditions; seepage conditions;
hydraulic transmissibility, erosion control; surface drainage; local or
area subsidence; slope stability; creep and other such site
characteristics. Be alert for any evidence of possible oil and/or chemical
contamination on the site and, as a minimum, conduct field evaluation of
each boring sample with equipment capable of detecting petroleum product
contamination. If conditions are discovered which require negotiation,
notify the PDE verbally and recommend in writing such additional sampling,
tests or studies as required to ensure the adequacy of the site and
foundation data. After completion of borings, backfill holes and restore
ground surface including pavements to the original condition immediately,
unless monitoring of water levels is required. Grout and seal boreholes
(a) to prevent vertical transmission of water from different acquifers if
found, (b) to seal off surface or near surface contaminants from entering
into ground, (c) when excavation below groundwater level is anticipated for
the project, or (d) when work is done on or around a dam or levee. The
grouting and sealing work, including the grout mix, shall be in accordance
with the EPA requirements.
For subsurface excavation and pumping out of water from flooded utility
structures to verify utilities, the activity Public Works Department or
Public Works Center may be able to provide assistance. When this
assistance is unavailable and the service is required, then a reimbursable
item will be negotiated for this effort with the A-E.
6.2.2 Boring Records: Maintain a complete record of each hole. Include
the ground elevation referred to an established datum, a description of the
character of the materials encountered (include classification by visual or
laboratory examination and an indication of the firmness in place),
elevations where encountered, elevations where loss of drilling fluid or
cave-ins occurred, the elevation of the ground water level first
encountered, the elevation of the ground water level after it has
6-2
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