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The Geoprofessional Business Association (GBA)
has prepared this advisory to help you — assumedly
a client representative — interpret and apply this
geotechnical-engineering report as effectively
as possible. In that way, clients can benefit from
a lowered exposure to the subsurface problems
that, for decades, have been a principal cause of
construction delays, cost overruns, claims, and
disputes. If you have questions or want more
Information about any of the Issues discussed below,
contact your GSA -member geotechnical engineer.
Active Involvement In the Geoprofessional Business
Association exposes geotechnical engineers to a
wide array of risk -confrontation techniques that can
be of genuine benefit for everyone involved with a
construction project.
Geotechnical-Engineering Services Are Performed for
Specific Purposes, Persons, and Projects
Geotechnical engineers structure their services to meet the specific
needs of their clients. A geotechnical-engineering study conducted
for a given civil engineer will not likely meet the needs of a civil -
works constructor or even a different civil engineer. Because each
geotechnical-engineering study is unique, each geotechnical-
engineering report is unique, prepared solely for the client. Those who
rely on a geotechnical-engineering report prepared for a different client
can be seriously misled. No one except authorized client representatives
should rely on this geotechnical-engineering report without first
conferring with the geotechnical engineer who prepared it. And no one
— not even you — should apply this reportfor any purpose or project except
the one originally contemplated.
Read this Report in Full
Costly problems have occurred because those relying on a geotechnical-
engineering report did not read it in its entirety. Do not rely on an
executive summary. Do not read selected elements only. Read this report
in full.
You Need to Inform Your Geotechnical Engineer
about Change
Your geotechnical engineer considered unique, project -specific factors
when designing the study behind this report and developing the
confirmation -dependent recommendations the report conveys. A few
typical factors include.
. the clients goals, objectives, budget, schedule, and
risk -management preferences;
• the general nature of the structure involved, its size,
configuration, and performance criteria;
• the structure's location and orientation on the site; and
• other planned or existing site improvements, such as
re,tgiffl g walls, access roads, parking lots, and
1 unde;ground utilities.
Report.
Typical changes that could erode the reliability of this report include
those that affect
• the site's size or shape;
• the function of the proposed structure, as when its
changed from a parking garage to an office building, or
from a light -industrial plant to a refrigerated warehouse;
• the elevation, configuration, location, orientation, or
weight of the proposed structure;
• the composition of the design team; or
• project ownership.
As a general rule, always inform your geotechnical engineer of project
changes — even minor ones — and request an assessment of their
impact. The geotechnical engineer who prepared this report cannot accept
responsibility or liability forproblems that arise because the geotechnical
engineer was not informed about developments the engineer otherwise
would have considered.
This Report May Not Be Reliable
Do not rely on this report if your geotechnical engineer prepared it:
• for a different client;
for a different project;
for a different site (that may or may not include all or a
portion of the original site); or
before important events occurred at the site or adjacent
to it; a g., man-made events like construction or
environmental remediation, or natural events like floods,
` droughts, earthquakes, or groundwater fluctuations.
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Note, too, that it could be unwise to rely on a geotechnical-engineering
Feport whose reliability may have been affected by the passage of time,
because of factors like changed subsurface conditions; new or modified
codes, standards, or regulations; or new techniques or tools. If your
geotechnical engineer has not indicated an `apply -by" date on the report,
ask what it should be, and, in general, if you are the least bit uncertain
about the continued reliability of this report, contact your geotechnical
engineer before applying it. A minor amount of additional testing or
analysis — if any is required at all — could prevent major problems.
Most of the "Findings" Related in This Report Are
Professional Opinions
Before construction begins, geotechnical engineers explore a site's
subsurface through various sampling and testing procedures.
Geotechnical engineers can observe actual subsurface conditions only at
those specific locations where sampling and testing were performed. The
data derived from that sampling and testing were reviewed by your
geotechnical engineer, who then applied professional judgment to
form opinions about subsurface conditions throughout the site. Actual
sitewide-subsurface conditions may differ — maybe significantly — from
those indicated in this report. Confront that risk by retaining your
geotechnical engineer to serve on the design team from project startto
project finish, so the individual can provide informed guidance quickly,
wheneve[ needed.
This Report's Recommendations Are
Confirmation -Dependent
The recommendations included in this report — including any optic
or alternatives - are confirmation -dependent. In other words, they a
not final, because the geotechnical engineer who developed them rel
heavily on judgment and opinion to do so. Your geotechnical engine
can finalize the recommendations only after observing actual subsurj
conditions revealed during construction. If through observation you
geotechnical engineer confirms that the conditions assumed to exist
actually do exist, the recommendations can be relied upon, assumin,
no other changes have occurred. The geotechnical engineer who preps
this report cannot assume responsibility or liability far confirmation -
dependent recommendations if you fail to retain that engineer to perfo
construction observation.
This Report Could Be Misinterpreted
Other design professionals' misinterpretation of geotechnical-
engineering reports has resulted in costly problems. Confront that
by having your geotechnical engineer serve as a full-time member
design team, to:
• confer with other design -team members,
• help develop specifications,
• review pertinent elements of other design professionals'
plans and specifications, and
• be on hand quickly whenever geotechnical-engineering
guidance is needed.
You should also confront the risk of constructors misinterpreting this
report.. Do so by retaining your geotechnical engineer to participate in
prebid and preconstruction conferences and to perform construction
observation.
Give Constructors a Complete Report and Guidance
Some owners and design professionals mistakenly believe they can shift
unanticipated -subsurface -conditions liability to constructors by limitinf
the information they provide for bid preparation. To help prevent
the costly, contentious problems this practice has caused, include the
complete geotechnical-engineering report, along with any attachments
or appendices, with your contract documents, but be certain to note
conspicuously thatyou've included the material for informational
purposes only. To avoid misunderstanding, you may also want to note
that "informational purposes" means constructors have no right to rely
on the interpretations, opinions, conclusions, or recommendations in
the report, but they may rely on the factual data relative to the specific
times, locations, and depths/elevations referenced. Be certain that
constructors know they may learn about specific project requirements,
including options selected from the report, only from the design
drawings and specifications. Remind constructors that they may
perform their own studies if they want to, and be sure to allow enough
time to permit them to do so, Only then might you be in a position
to give constructors the information available to you, while requiring
them to at least share some of the financial responsibilities stemming
from unanticipated conditions. Conducting prebid and preconstruction
conferences can also be valuable in this respect.
Read Responsibility Provisions Closely
Some client representatives, design professionals, and constructors do
not realize that geotechnical engineering is far less exact than other
engineering disciplines. That lack of understanding has nurtured
unrealistic expectations that have resulted in disappointments, delays,
cost overruns, claims, and disputes. To confront that risk, geotechnical
engineers commonly include explanatory provisions in their reports.
Sometimes labeled "limitations," many of these provisions indicate
where geotechnical engineers' responsibilities begin and end, to help
others recognize their own responsibilities and risks. Read these
provisions closely. Ask questions. Your geotechnical engineer should
respond fully and franl4y.
Geoenvironmental Concerns Are Not Covered
The personnel, equipment, and techniques used to perform an
environmental study — e.g., a "phase-ond' or "phase-twd' environmental
site assessment — differ significantly from those used to perform
a geotechnical-engineering study. For that reason, a geotechnical-
engineeringreport does not usually relate any environmental findings,
conclusions, or recommendations; e.g., about the likelihood of
encountering underground storage tanks or regulated contaminants.
Unanticipated subsurface environmental problems have led to project
failures. If you have not yet obtained your own environmental
information, ask your geotechnical consultant for risk -management
guidance. As a general rule, do not rely on an environmental report
prepared for a different client, site, or project, or that is more than six
months old.
Obtain Professional Assistance to Deal with Moisture
Infiltration and Mold
While your geotechnical engineer may have addressed groundwater,
water infiltration, or similar issues in this report, none of the engineer's
services were designed, conducted, or intended to prevent uncontrolled
migration of moisture — including water vapor — from the soil through
building slabs and walls and into the building interior, where it can
cause mold growth and material -performance deficiencies. Accordingly,
proper implementation of the geotechnical engineer's recommendations
will notof itself be sufficient to prevent moisture infiltration. Confront
the risk of moisture infiltration by including building -envelope or mold
specialists on the design team. Geotechnical engineers are not building -
envelope or mold specialists.
- 'GEOPROFESSIONAL
BUSINESS
'+ ASSOCIATION
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Telephone: 301 /565-2733
e-mail: info@geoprofessional.grg www.geoprofessional.org
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Copyright 2016 by Geoprofessional Buslness Association (GBA). Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly
prohibited, except with GBAs specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission
of GBA, and only for purposes ofscholarly research or book review. Only members of GBA may use this document or its wording as a complement to or as an element of a report ofany
kind, Any other firm, indrdual, or other entity that so uses this document without being a GBA member could be committing negligent