Appendix 3-2.

This file provides a listing of the water-quality parameter number in the numerical sequence of the U.S. Geological Survey (USGS) 
National Water Information System (NWIS) for which an authoritative correspondence to parameters of the Texas Commission on Environmental Quality (TCEQ). 
For example, water temperature in Celsius in the NWIS system is parameter "00010". For this report, the letter "P" is prepended to the parameter number to 
as to mitigate confusion between numerical data values and the associated parameter. The listed parameters at the end of this file are those parameters 
for which correspondence was made and data files are provided for download.

#  00003  - Sampling Depth, in feet
#  00010  - Temperature, water, degrees Celsius
#  00095  - Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius
#  00300  - Dissolved oxygen, water, unfiltered, milligrams per liter
#  00400  - pH, water, unfiltered, field, standard units
#  00480  - Salinity, water, unfiltered, parts per thousand
#  00600  - Total nitrogen, water, unfiltered, milligrams per liter
#  00630  - Nitrate plus nitrite, water, unfiltered, milligrams per liter as nitrogen
#  00665  - Phosphorus, water, unfiltered, milligrams per liter as phosphorus
#  00666  - Phosphorus, water, filtered, milligrams per liter as phosphorus
#  00900  - Hardness, water, milligrams per liter as calcium carbonate
#  00915  - Calcium, water, filtered, milligrams per liter
#  00925  - Magnesium, water, filtered, milligrams per liter
#  00927  - Magnesium, water, unfiltered, recoverable, milligrams per liter
#  00929  - Sodium, water, unfiltered, recoverable, milligrams per liter
#  00930  - Sodium, water, filtered, milligrams per liter
#  00935  - Potassium, water, filtered, milligrams per liter
#  00937  - Potassium, water, unfiltered, recoverable, milligrams per liter
#  00940  - Chloride, water, filtered, milligrams per liter
#  00945  - Sulfate, water, filtered, milligrams per liter
#  00950  - Fluoride, water, filtered, milligrams per liter
#  00951  - Fluoride, water, unfiltered, milligrams per liter