|Abstract:||As part of the National Water-Quality
Assessment Program, surface-water and ground-water
samples were collected in 1994 and 1995 for analysis
of common constituents, nutrients, dissolved organic
carbon, trace elements, radioactivity, volatile organic
compounds, and pesticides to characterize surface-
water quality and shallow ground-water quality and to
determine factors affecting water quality in the Rincon
Valley, south-central New Mexico. Samples of surface
water were collected from three sites on the Rio Grande
and from sites on three agricultural drains in the Rincon
Valley in January 1994 and 1995, April 1994, and
October 1994. Ground-water samples were collected in
late April and early May 1994 from 30 shallow wells
that were installed during the investigation.
Dissolved-solids concentrations in surface water
ranged from 434 to 1,510 milligrams per liter (mg/L).
Dissolved-solids concentrations were smallest in water
from the Rio Grande below Caballo Dam and largest in
the drains. Nitrite plus nitrate concentrations ranged
from less than 0.05 to 3.3 mg/L as nitrogen, and
ammonia concentrations ranged from less than 0.015 to
0.33 mg/L as nitrogen in surface-water samples.
Trace-element concentrations in surface water
were significantly smaller than the acute-fisheries
standards. One or more pesticides were detected in 34
of 37 surface-water samples. DCPA (dacthal) and
metolachlor were the most commonly detected
pesticides. No standards have been established for the
pesticides analyzed for in this study.
Dissolved-solids concentrations in shallow
ground water ranged from 481 to 3,630 mg/L. All but 2
of 30 samples exceeded the secondary maximum
contaminant level for dissolved solids of 500 mg/L.
Water from about 73 percent of the wells sampled
exceeded the secondary maximum contaminant level
of 250 mg/L for sulfate, and water from about 7 percent
of the wells sampled exceeded the secondary
maximum contaminant level of 250 mg/L for chloride.
Nitrite plus nitrate concentrations ranged from less
than 0.05 to 33 mg/L as nitrogen in shallow ground
water. Water from about 17 percent of the well samples
exceeded the maximum contaminant level of 10 mg/L
as nitrogen for nitrite plus nitrate.
Trace-element concentrations in shallow ground
water generally were small (1 to 10 micrograms per
liter). The proposed maximum contaminant level of 20
micrograms per liter for uranium was exceeded in
about 13 percent of the samples. The secondary
maximum contaminant level of 300 micrograms per
liter for iron was exceeded in about 17 percent of the
samples and of 50 micrograms per liter for manganese
was exceeded in about 83 percent of the samples.
Samples from about 23 percent of the wells exceeded
the maximum contaminant level of 15 picocuries per
liter for gross alpha activity.
One or more pesticides were detected in water
from 12 of 30 wells sampled. The pesticides or
pesticide metabolites diazinon, metolachlor,
napropamide, p,p‘-DDE, and prometon were detected
in one or more samples. Metolachlor and prometon
were the most commonly detected pesticides. Health
advisories for the pesticides detected in shallow ground
water (no maximum contaminant levels have been
established for the pesticides detected) are 10 to 300
times larger than the concentrations detected.
Infiltration, evaporation, and transpiration of
irrigation water are important factors affecting the
concentrations of common constituents in shallow
ground water in the Rincon Valley. Dissolution and
precipitation of minerals and mixing of shallow ground
water and inflow of ground water from adjacent areas
also affect the composition of shallow ground water
and water in the drains.
Relatively large nitrite plus nitrate
concentrations in several shallow ground-water
samples indicate leaching of fertilizers in some areas of
|Genre: ||USGS Numbered Series
|Citation Author: ||Anderholm, Scott K.
|Citation Contributing Office: ||USGS New Mexico Water Science Center
|Citation Datum: ||
|Citation Day: ||
|Citation Edition: ||-
|Citation Editor: ||
|Citation End Page: ||
|Citation Issue: ||
|Citation Keywords: ||
|Citation Language: ||ENGLISH
|Citation Larger Work Title: ||
|Citation LatN: ||0325500
|Citation LatS: ||0322500
|Citation LonE: ||-1065500
|Citation LonW: ||-1072500
|Citation Month: ||
|Citation No Pagination: ||
|Citation Number Of Pages: ||
|Citation Online Only Flag: ||
|Citation Phsyical Description: ||vii, 117 p.
|Citation Projection: ||
|Citation Public Comments: ||Prepared in Cooperation with the New Mexico Environment Department
|Citation Publisher: ||Geological Survey (U.S.)
|Citation Series: ||Water-Resources Investigations Report
|Citation Series Code: ||WRI
|Citation Series Number: ||2002-4188
|Citation Search Results Text: ||Water-Quality Assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas--Surface-Water Quality, Shallow Ground-Water Quality, and Factors Affecting Water Quality in the Rincon Valley, South-Central New Mexico, 1994-95; 2002; WRI; 2002-4188; Anderholm, Scott K.
|Citation Start Page: ||
|Citation Volume: ||
|Citation Year: ||2002
|Text: ||Water-Quality Assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas--Surface-Water Quality, Shallow Ground-Water Quality, and Factors Affecting Water Quality in the Rincon Valley, South-Central New Mexico, 1994-95; 2002; WRI; 2002-4188; Anderholm, Scott K.
|URL (THUMBNAIL): ||http://pubs.er.usgs.gov/thumbnails/usgs_thumb.jpg
|URL (INDEX PAGE): ||http://pubs.usgs.gov/wri/wri02-4188/
|Date Other: ||Sat, 1 Mar 2003 00:00 -0600
|Publisher: ||Geological Survey (U.S.)