Changes in Parameter Names Used in the NWIS Parameter Code Dictionary

In Reply Refer To:
Mail Stop 412                                           					

April 30, 2003


Office of Water Quality Technical Memorandum 2003.03

Subject:  Changes in Parameter Names Used in the NWIS Parameter Code Dictionary

Purpose:
The purpose of this memo is to announce changes in parameter names in the 
National Water Information System (NWIS) Parameter Code Dictionary (PCD).  
These changes will be incorporated in the May 2003 release of the PCD.  

Description:
The changes affect the parameter short name, long name, and column 
headings.  They include 
   (1) conversion of text from all upper case to mixed case, 
   (2) standardization of word usage (for example, "dissolved" has mostly 
       been replaced by "filtered"), 
   (3) systematization of the order in which qualifiers appear in a name,
   (4) revisions and corrections to chemical names to provide consistency, and
   (5) changes in the default reporting order for publication tables.

Some chemical names have been changed to nomenclature recommended by the 
International Union of Pure and Applied Chemistry (IUPAC).  Some names 
have changed significantly, making it difficult to identify these 
parameters without knowing the parameter code.  For example, triazine 
degradate names have been changed as follows:

   Old Name            New Name                                            Acronym
 
didealkylatrazine      chlordiamino-s-triazine                             CAAT
deisopropylatrazine    2-chloro-6-ethylamino-4-amino-s-triazine            CEAT
deethylatrazine	       2-chloro-4-isopropylamino-6-amino-s-triazine        CIAT
deisopropylhydroxy-    2-hydroxy-6-ethylamino-4-amino-s-triazine           OEAT
     atrazine
deethylhydroxyatrazine 2-hydroxy-4-isopropylamino-6-amino-s-triazine       OIAT
hydroxyatrazine        2-hydroxy-4-isopropylamino-6-ethylamino-s-triazine  OIET

To help users find parameter codes using the old parameter names, a 
spreadsheet containing both old and new names is available for download 
from the Water-Quality User group (Phoenix) web site at:

http://wwwok.cr.usgs.gov/nawqa/phoenix/doc.html

This spreadsheet also includes Chemical Abstracts Service (CAS) Registry 
Numbers, if known.  

Users are reminded that parameter code long names are the definitive names 
for all parameters.  Short name and column names in publication tables 
almost always contain abbreviations and synonyms for chemical names.  
Parameter code long names should always be consulted for the accurate 
identification of a parameter.

Questions about these changes should be directed to Kathy Fitzgerald 
(mailto:kkfitz@usgs.gov).

Timothy L. Miller /s/
Chief, Office of Water Quality

This memorandum does not supersede any other Office of Water Quality 
Technical Memorandum.

Distribution:  All WRD Employees