7623

• UCREFRP Catalog Number: 7623
• Author: Lamb, B. L. and D. A. Sweetman.
• Title: Guidelines for Preparing Expert Testimony in Water Management Decisions Related to Instream Flow Issues.
• USFW Year: 1979.
• USFW - Doc Type: Instream Flow Information Paper No. 1, Revised,
• Copyright Material: NO

clean-up techniques, in order to eliminate the
presence of DDE, or PCB, or any other artifacts
which could have caused interference on the GLC
columns, and, therefore, exaggerated or made too
large the results which you found for aldrin and/or
dieldrin?
A. Really there are two components to the
question. One is the sampling and one is the
in-house analysis of the sample.
You are asking once the sample is in-house and in a
correctly identified manner, how it is analyzed?
Q. That is correct.
A. In this particular investigation, some of the
peculiarities of saltwater chemistry said it really
wasn't that necessary to go through elaborate
separation schemes with the type of gas chroma-
tography, the type of detector that was employed.
We did use different columns so we wouldn't catch
any of these places where one type of compound
overlaps another, or one reacts in a column and
produces a spurious peak of one sort or another.
In other types of work, sometimes medium clean-up,
extensive clean-up, might be needed, but not in in
this case.
Q. Are you saying that because the samples were
taken from saltwater, in this case it was actual
seawater, wasn't it --
A. That is correct.
Q. -- that there were no artifacts that could
have been present in the seawater?
A. Oh, there may have been many artifacts. But
using the particular column, the inlet design, the
type of detector, the sensitivity settings, the
thermal settings, flow rates, all of those
parameters, there was no interference at this
point. There were lots of other items that could be
seen on some of the chromatograms, but they weren't
of interest for this particular paper.
It must be emphasized that a judge cannot easily determine what is-"harm-
less analytical error"; as a lawyer in a strange field, he must rely upon
certain procedures which others in the field have called the standard methods
for analysis. If the witness cannot tick off the requisite procedures, he
should be prepared to explain why he used a different method, and preferably
to be able to point to some published work which sanctions the method he used.
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