Some people have used nitrogen isotopes, other have used major ion ratios to
differentiate between wastewater and agricultural sources.
I can try to dig up some references if you want more information.
Luis
Prof. Luis E. Marin
Chair, Water Network
Mexican Academy of Sciences
Instituto de Geofísica
Universidad Nacional Autónoma de México
Cd. Universitaria
México, D.F., México
CP 04510
Telephone +52 555 622 4212
Mobile +52 555 418 10 00
Fax +52 555 550 2486
For large files, please email them to: lmarin@...
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