Oregon perchlorate detections

[Lenny Siegel <lsiegel@cpeo.org>]

===========================================================
Your opinion counts! We're conducting a survey for a
computer service/repair company. When you complete our
survey, you will also be entered into a drawing for one of
ten $100 prizes. Just click
http://click.topica.com/caab6PVaVxieSa8wsBba/ Val Rad
===========================================================
Perchlorate in the Lower Umatilla Basin Groundwater Management Area -
Issues and Answers

Oregon Department of Environmental Quality
Water Quality Division
Eastern Region
www.deq.state.or.us
Last Updated: 3/29/04
By: Phil Richerson
DEQ 04-ER-011

What was done?

The Lower Umatilla Basin has been known to have elevated nitrate levels
since before 1990. As part of an ongoing effort to track nitrate levels in
groundwater DEQ collected, and EPA analyzed, water samples from 133 wells
in the area. In addition to testing for nitrate, EPA analyzed for
perchlorate, which had not previously been part of the analysis.
Perchlorate was found in low levels in over half of the wells. In most of
the wells that had perchlorate the concentration was below 4 parts per
billion (ppb) the most commonly used public health goal. Some wells,
however, were above that level.

?

Why am I hearing about perchlorate now?

The Lower Umatilla Basin Groundwater Management Area (GWMA) ? a portion of
northern Morrow and northwestern Umatilla Counties (including the
Hermiston and Boardman areas) was established in 1990 as a result of
demonstrated area wide nitrate contamination. The Oregon DEQ, with
assistance from EPA, recently conducted a regional groundwater sampling
event. The event was a repeat of sampling done in 1992 to characterize
regional groundwater quality. This repeat sampling was intended to help
identify changes in nitrate concentration since the establishment of the
GWMA. Perchlorate was added to the analysis because it had been detected
in some wells in the area. This sampling event found perchlorate in over
half of the 133 wells sampled. Of the wells where perchlorate was
detected, concentrations ranged from 1 ppb to 25 ppb. DEQ received the
final results of the sampling in mid March 2004 and released the results
to the affected well owners shortly thereafter.

Of the 133 wells tested for perchlorate, 61 (46%) had none detected. The
wells tested included monitoring wells, irrigation wells, domestic
(household water) wells, a community well and a livestock well. Fifty four
domestic (mostly privately owned and shallow) wells were included. Twenty
five of those had perchlorate detected at levels ranging from
approximately 1 ppb to 7 ppb. Twelve irrigation wells were tested. Nine of
those had perchlorate detected at levels ranging from approximately 1 to 4
ppb. The remaining wells were groundwater monitoring wells (not used for
drinking or for irrigation). Thirty seven out of 63 monitoring wells had
perchlorate detected at levels ranging from 1 to 25 ppb.

?

for the entire fact sheet, see
http://www.deq.state.or.us/wq/wqfact/FSPerchlorateLowerUmatillaGW.pdf

--
Lenny Siegel
Director, Center for Public Environmental Oversight
c/o PSC, 278-A Hope St., Mountain View, CA 94041
Voice: 650/961-8918 or 650/969-1545
Fax: 650/961-8918
<lsiegel@cpeo.org>
http://www.cpeo.org

===========================================================
$6.95 .com Domain Name Sale!
Limited Time! ICANN Accredited GoDaddy!
http://click.topica.com/caab7pQaVxieSa8wsBbf/ GoDaddy
===========================================================

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CPEO: A DECADE OF SUCCESS.  Your generous support will ensure that our
important work on military and environmental issues will continue.
Please consider one of our donation options.  Thank you.
http://www.groundspring.org/donate/index.cfm?ID=2086-0|721-0