Attachment 7B - Site Based Stormwater Manamgment Plan by ADG

Jun O7 O7 O4:39p

coffey? geotechnics

SPECIALISTS MANAGING THE EARTH

Important information about your Coffey Report

As a client of Coffey you should know that site subsurface conditions cause more construction
problems than any other factor. These notes have been prepared by Coffey to help you
interpret and understand the limitations of your report.

Your report is based on project specific criteria
Your report has been devcloped on the basis of your
unique project specific requirements as understood
by Coftey and applies only to the site investigated.
Project criteria typically include the general nature of
the project; its size and configuration; the localion of
any structures on the site, other site improvements;
the presence of underground utilitins; and the additional
risk imposed by scope-of-service limitations imposed
by the client. Your report should not be used if there
are any changes to the project without first asking
Cottey to assess how tactors that changed stibsequent
to the date of the report affect the report's
recommendations. Coffey cannot accept responsibility
for problems that may occur due lo changed factors
if they are not consulted.

Subsurface conditions can change

Subsurface conditions are crealed by nalural processes
and the activity. of man. For example, water levels
can vary with time, fill may be placed ona site and
pollutants may migrate with time. Because a report
is based on condilions which existed at the time of
subsurface exploration, decisions should not be based
on a report whose adequacy may have been affected
by time. Consult Coffey to be advised how tirne may
have impacted on the project.

 

 

Interpretation of factual data

Site assessment identifies actual subsurface conditions
only at those points where samples are taken and
whon they are taken. Data derived from literature
and external data source review, sampling and
subsequent laboratory testing are interpreted by
geologists, engineers or scientists to provide an
opinion about overall site conditions, their likely
impact on the proposed development and recommended
actions. Actual conditions may differ from those inferred
to cxist, because no professional, no mattcr how
qualified, can reveal what is hidden by

Coffey Geotechnics Pty Ltd ABN 93 056 929 483

earth, rock and time. The actual interface between
materials may be far more gradual or abrupt than
assumed based on the facts oblained. Nothing can
be done to change the aclual site conditions which
oxist. but steps can be taken to reduce the impact of
unexpected conditions. For this reason, owners
should retain the services of Coffey through the
development stage, to identify variances, conduct
additional tests if required, and recommend solutions
to problems encountered on site.

Your report will only give

minary recommendations —_

Your report is based on the assumption that the
site conditions as revealed through sclective
point sampling are indicative of actual conditions
throughout an areca. This assumplion cannot be
substantiated until project implementation has
commenced and therefore your report recommendations
can only be regarded as preliminary. Only Coffey,
who prepared the report, is fully tamiliar with the
background information needed to assess whether
or not the report's recommendations arc valid and
whether or not changes should be considered as
the project develops. If another party undertakes
the implementation of the recommendations of this
report there is a risk that the report will be misinterpreted
and Coffey cannot be held responsible tor such
misinterpretation.

 

Your report is prepared for

specific purposes and persons .
To avoid misuse of the information contained in your
report it is recommended that you confer with Coffey
before passing your report on to another party who
may not be familiar with the background and the
purpose of the report. Your report should not be
applied to any project other than that originally
specified at the time the report was issucd.