Presampling - Field Sampling: Principles and Practices in Environmental Analysis - page 56

needed later the required information is easy to find. The table of contents is also handy
in connecting observations and data collected at different times and bringing them
together. Samples will be taken, and two weeks later the analytical results will be
returned. In the meantime entries have been made in the project topic. Information about
how and when the samples were taken will need to be combined with the analytical
results in reports, so the ability to readily access the sampling data and the analytical
results is important.
The date on which entries are made in the project notebook must be placed at the top of
each page. In some cases it may also be necessary to note the times at which activities
were undertaken either at the top of the page or in the body of the write-up. In Figure 3.1
the date is at the top of the page on the left and follows a notation that the samples were
taken in the afternoon (i.e., p.m.).
When samples are taken, the numbers they are given should refer back to the project
topic. Specifically, the sample numbers should refer back to the page number where a
description of the sampling process and the location of the sample are given. It is usually
a good idea to prefix the sample number with the initials of the person taking the
samples. In addition, people often like to have the sample number include a reference to
date and time. For instance, the sample number might be AC12A31a1 12102 pm. Here
12A is the field number, 31a the sample number in the project book, 112102 the date, and
pm the time of sampling. As can be seen, this can produce an unwieldy sample number if
carried too far.
In Figure 3.1 the sampler's initials are at the top of the page and each sample entry
begins with his initials followed by the page number. The first entry has a small letter a
following the sample number. This tells the reader that it is the first sample noted on this
page. Also note that the sample number is repeated in the left-hand margin for easy
reference. Under each sample number various observations are made about the sample as
it is obtained. Such observations can add critical insight into the nature of the sample and
its components.
An example of a simple observation is the color of a soil sample, which can be
important in interpreting sampling and analytical results. A soil sample showing color
variations of reds, browns, grays, or blues indicates that the soil is under reducing
conditions during a significant period of time during the year. The ease or difficulty of
inserting the sampling tool is another observation that can indicate the occurrence of
compacted layers. Samples might also show a change in texture or the occurrence of a
gravel or sandy layer. As mentioned in Chapter 2, all of these are important to note
because they can indicate where additional sampling may be needed or where a
contaminant is likely to be found.
In a similar fashion observations about water and air samples must be made as they are
taken. These may include color, suspended matter, and odor, and may help in
identification of the nature and concentration of the contaminant or contaminants.
Observations will also provide either clues or evidence as to the source of the
contamination, which could be essential in preventing further contamination.