Janet,
We can provide the analyses that Jorge requested, using the TC/EA method
that Steven Silva mentioned in his message. I will contact Jorge
directly concerning costs and sampling requirements.
Dennis Coleman
Isotech Laboratories, Inc.
www.isotechlabs.com


-----Original Message-----
From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On
Behalf Of Janet Gabites
Sent: Tuesday, June 14, 2005 6:32 PM
To: [log in to unmask]
Subject: [ISOGEOCHEM] request for analyses

I received the following request for analyses. We are not set up for
this,
so I offered to post to the list in the hope that some other lab can
help.

Thanks,
Janet Gabites


>We are doing a research in a highland lake here in Colombia trying to
>discriminate sources of NO3 pollutants. We need to know the levels of
18O
>and 15N in water samples of stream and lake waters. Current NO3 levels
range
>from 3 to 25 mg/L. We want to trace nitrate sources using natural
stable
>isotopes (15N and 18O). We expect to use the method describe by Silva
et al,
>(2000) (A new method for collection of nitrate from fresh water and the
>analysis of nitrogen and oxygen isotope ratios S.R. Silva a, * , C.
Kendall
>a , D.H. Wilkison b , A.C. Ziegler c , C.C.Y. Chang a , R.J. Avanzino
a).
>
>I would like also to know if your laboratory has the capability and
>availability to process and analyze around 300 samples using the resins
>describe by Silva. If positive I would appreciate you can give me an
idea
>of the costs for processing this material and the procedures to follow
in
>case we use your services.
>
>Sincerely,
>
>
>Jorge Rubiano
>Postdoctoral Research Fellow
>Land Use Project
>CIAT- International Center for Tropical Agriculture
>Cali
>Colombia
>
>[log in to unmask]
>Tel: 572-445-0493 or 1-650-833-6625
>Fax: 572-445-0073 or 1-650-833-6626
>http://gisweb.ciat.cgiar.org
>http://www.waterforfood.org

Janet Gabites,
Stable Isotope Facility,
Pacific Centre for Isotope and Geochemical Research,
Department of Earth and Ocean Sciences,
The University of British Columbia,
Vancouver, B.C. V6T 1Z4
ph 604-822-6654
fax 604-822-6088
http://www.eos.ubc.ca/research/pcigr/PCIGR.htm