71 
QA/QC comments. Fields that distinguish the project and source for each record 
should also be created, to allow for station filtering. In addition, you may also 
want to create a field for segment ID (e.g., OH, TF1, MH, etc.) for each record. 
6. In this master dataset, create a field called “input”. This will be the field that will 
be copied and pasted into the Interpolator. 
The Interpolator reads a record with the following format: 
EASTING,NORTHING,DEPTH,PARAMETER,STATION 
The “input” field should be a concatenation of the pertinent fields in your master 
database. A comma is needed between each value, so create a “comma” field that 
you reference in the concatenate formula. 
7. Replicate samples should be averaged together prior to interpolation if the time 
scale you have chosen is greater than a day. This is because the interpolator will 
automatically average multiple observations present. If the interpolator is a daily 
interpolation, the interpolator will take the replicates on that day and average 
them as is appropriate. However, if it is a monthly interpolation, and the daily 
replicates have not been previously averaged into a single value, then the repli¬ 
cates will be treated as independent observations and given undue weight in the 
monthly average. 
8. The QA/QC field should be reviewed and only data meeting appropriate QA/QC 
requirements should be used in the following interpolation steps. Cruise-track 
data associated with such codes as NQR, NNF, GPF, and GNV are to be 
excluded, while data flagged as algal blooms (CAB) should be left in. In Vir¬ 
ginia, consult the table in the Data Disclaimer and Info section of www.vecos.org 
for a description of codes. 
STEP 3. IMPORTING THE DATA INTO THE INTERPOLATOR 
9. Filter the master database so that it only shows data for the specific time period 
(e.g., March 1,2005) and from the type of stations (e.g., long-term CPB stations) 
that is desired. Fixed stations alone should be interpolated by month, while fixed 
stations + DFLO cruise-tracks should be interpolated by day. 
10. Copy and paste the “input” field into a text editor, such as Notepad. 
11. The first five lines of this text file are descriptive, providing info to both the 
reader and the Interpolator. They should look something like this: 
CHL for James March 2005 long-term CPB stations 
CHL, Chlorophyll concentration 
05/02/2005,05/25/2005 
07/10/2007:11:25 
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The first four lines provide general information (which would show if you gener¬ 
ated a map). The third line gives the range of sampling dates for the input data, 
and the fourth line gives the current date and time (you can put any date and 
time, but it should be formatted as shown). The fifth line is the critical one for 
the Interpolator. This is the number of data points in the input. If this number is 
appendix g • Chlorophyll a Assessment Protocol 
