WATER POLLUTION CONTROL RESEARCH SERIES • 16060 EGS 01/71
INFILTRATION RATES AND GROUNDWATER
QUALITY BENEATH CATTLE FEEDLOTS,
TEXAS HIGH PLAINS
ENVIRONMENTAL PROTECTION AGENCY • WATER QUALITY OFFICE
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WATER POLLUTION CONTROL RESEARCH SERIES
The Water Pollution Control Research Series describes
the results and progress in the control and abatement
of pollution in our Nation's waters. They provide a
central source of information on the research , develop-
ment, and demonstration activities in the Water Quality
Office, Environmental Protection Agency, through inhouse
research and grants and contracts with Federal, State,
and local agencies, research institutions, and industrial
organizations.
Inquiries pertaining to Water Pollution Control Research
Reports should be directed to the Head, Project Reports
System, Office of Research and Development, Water Quality
Office, Environmental Protection Agency, Room 1108,
Washington, D. C. 20242.
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INFILTRATION RATES AND GROUNDWATER
QUALITY BENEATH CATTLE FEEDLOTS,
TEXAS HIGH PLAINS
by
Texas Tech University
Department of Geosciences
Lubbock, Texas 79409
for the
WATER QUALITY OFFICE
ENVIRONMENTAL PROTECTION AGENCY
Project #16060EGS
Contract f 14-12-804
January, 1971
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 65 cents
Stock Number 5501-0125
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EPA Review Notice
This report has been reviewed by the Water Quality Office,
EPA, and approved for publication. Approval does not sig-
nify that the contents necessarily reflect the views and
policies of the Environmental Protection Agency, nor does
mention of trade names or commercial products constitute
endorsement or recommendation for use.
11
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ABSTRACT
Detailed field and laboratory studies of five feedlots were
conducted to determine field seepage rates and distributive
geometry of infiltrated runoff. Practical field seepage
rates at these sites ranged from 2 to 20 feet/year. Disper-
sal rates of ions in the groundwater zone varied from 45 to
400 feet/year.
Nitrogen (N03, NC>2, NH4, Org-N) and common chemical parameters
(Ca, Mg, Na, K, Cl, 804, TDS, pH, and conductance) were deter-
mined in cores and groundwater samples; based on groundwater
analyses from 80 Texas High Plains feedlots, rates of con-
centration of NOj-N and Cl in groundwater beneath feedlots
range from 0.07 to 0.4 p.p.m. per year, and average 0.17 p.p.m.
per year.
Laboratory determined constant head vertical permeability
of cores from 22 feedlot sites revealed a range in values
of lO'2 to 10-6 cm/sec for Ogallala sediments, 10~4 to iO'7
cm/sec for near-surface material of floodplains and feedpen-
runoff surfaces, and values of 10~6 to 10~8 cm/sec for playa
clay.
Factors related to runoff-infiltration were correlated with
groundwater quality, and it was determined that local surfi-
cial material and regional soils patterns are closely related
to quality of groundwater beneath feedlots. Direct correla-
tion of water quality does not exist with feedpen-runoff
slope, cattle load, and surface-area ratios of drainage basin
to collection system.
This report is submitted in fulfillment of Project Number
16060EGS, Contract Number 14-12-804, under the (partial)
sponsorship of the Water Quality Office, Environmental Pro-
tection Agency.
Key Words: Nitrates, groundwater quality, Ogallala Forma-
tion, core chemistry, permeability, High Plains
geologic environment.
111
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CONTENTS
Section Page
I Conclusions 1
II Recommendations 3
III Introduction 5
Study Sites 5
Field Methods 9
Laboratory Methods 10
Nitrogen Cycle 11
IV Discussion of Study Area 13
Geomorphology-Geology 13
Groundwater 16
V Infiltration-Groundwater Quality
Relationships 18
VI Field Infiltration Rates and Dispersal
Rates in Groundwater 21
Field Site I 21
Field Site II 27
Field Site III 30
Field Site IV 39
Field Site V 42
Other Sites 42
VII Acknowledgments 53
VIII References Cited 55
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FIGURES
NO. PAGE
1 LOCATION OF CATTLE FEEDLOTS INVESTIGATED IN STUDY,
TEXAS HIGH PLAINS 6
2 AGE DISTRIBUTION OF FEEDLOTS IN STUDY 7
3 APPROXIMATE AVERAGE CATTLE LOAD ys_ YEAR FEEDLOT
ESTABLISHED 8
4 GENERALIZED SOIL TEXTURE MAP, TEXAS HIGH PLAINS ... 15
5 DISTRIBUTION OF OBSERVATION WELLS, FIELD SITE I ... 22
6 GAMMA LOG PROFILES, FIELD SITE I 23
7 SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE I 23
8 DISTRIBUTION OF NOs-N IN GROUNDWATER, FIELD SITE I. 26
9 DISTRIBUTION OF OBSERVATION WELLS, FIELD SITE II .. 28
10 GAMMA LOG PROFILES, FIELD SITE II 29
11 SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE II ... 29
12 DISTRIBUTION OF CHLORIDE IN GROUNDWATER,
FIELD "SITE II 32
13 DISTRIBUTION OF OBSERVATION WELLS, FIELD SITE III . 33
14 GAMMA LOG PROFILES, FIELD SITE III 35
15 SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE III .. 34
16 DISTRIBUTION OF N03-N IN'GROUNDWATER, FIELD
SITE III 38
17 DISTRIBUTION OF OBSERVATION WELLS, FIELD SITE IV .. 40
18 GAMMA LOG PROFILES, FIELD SITE IV 41
19 SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE IV*... 41
20 DISTRIBUTION OF OBSERVATION WELLS, FIELD SITE V ... 44
.21 GAMMA LOG PROFILES, FIELD SITE V 45
VI
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NO. PAGE
22 SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE V 45
23 DISTRIBUTION OF N03-N IN GROUNDWATER, FIELD SITE V. 48
24 AGE OF FEEDLOTS INVESTIGATED vs RANGE IN MAXIMUM
N03-N CONCENTRATION IN GROUNDWATER 50
25 AGE OF FEEDLOTS INVESTIGATED vs_ RANGE IN MAXIMUM
CHLORIDE CONCENTRATION IN GROUNDWATER 51
26 AGE OF FEEDLOTS INVESTIGATED vs RANGE IN MAXIMUM
CONDUCTANCE OF GROUNDWATER 52
VII
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TABLES
No. Page
I Relation of Feedlot-Runoff Seepage Factors
to Groundwater Quality, Texas High Plains 20
II Core Chemistry, Well #8, Field Site I 24
III Groundwater Chemistry, Field Site I 25
IV Core Chemistry, Well #9, Field Site II 30
V Groundwater Chemistry, Field Site II 31
VI Core Chemistry, Well #20, Field Site III 36
VII Groundwater Chemistry, Field Site III 37
VIII Core Chemistry, Well #7, Field Site IV 39
IX Groundwater Chemistry, Field Site IV 43
X Core Chemistry, Well #9, Field Site V 46
XI Groundwater Chemistry, Field Site V 47
Vlll
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CONCLUSIONS
1. Concentration values of ammoniacal, organic and nitrite
nitrogens, calcium, magnesium, sodium, potassium, and chlo-
ride in collected cattle-feedlot runoff exceed "normal" val-
ues for groundwater in the Ogallala Formation. Nitrate-
nitrogen in collected feedlot runoff may be found to be less
concentrated than in Ogallala groundwater. The occurrence
of high values of nitrate-nitrogen in Ogallala groundwater
in the vicinity of a feedlot is not always prima facie evi-
dence of a feedlot source.
2. Nitrite-nitrogen, ammoniacal and organic nitrogen occur
in high concentrations in collected feedlot runoff. These
ions usually are partially removed at the surface or retained
in the unsaturated subsurface environment and do not concen-
trate in the saturated zone in proportion (quantitatively)
to their surface occurrence. Removal of ammonia, organic
and nitrite-nitrogen is a result of nitrification-denitrification
reactions as well as volatilization of ammonia. Nitrogen
retention is in part accountable to clay mineral adsorption
and to bacterial fixation.
3. Surficial silt-clay mixtures of feedpens and/or runoff
surfaces exhibit secondary cementation in the form of root
fillings, vug and pore fillings, and veinlets. Below this
developed hardpan, soil densities are noticeably less and
permeability values are larger.
4. The ubiquitous Texas High Plains "caprock" caliche is
often porous and permeable below runoff collection systems.
Secondary solution of caliche is evidenced by vugs, second-
ary cementation of fractures and solution vugs, and by silt-
clay-fillings in the solution vugs and voids.
5. The unsaturated zone of the Ogallala Formation is slow-
to-rapidly permeable. Laboratory determined constant head
vertical permeability values in the unsaturated zone range'
from 10~2 to 10~6 cm/second. Laboratory determined perme-
ability values of playa sediments are usually less than 10~°
cm/second. Permeability values of feedpen and runoff sur-
face material range from 10~^ to 10"^ cm/second. Minimum
permeability of the surficial mantle and minimum permeability
values of the Ogallala sediments determine practical infil-
tration rates.
6. Regional soils patterns and the localized surficial sedi-
ments of playas are related to groundwater quality beneath
cattle feedlots. Total infiltration and infiltration rates
are greater in the sandy soil zones than in the hardland
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zones of the High Plains. The "ponding" part of playas that
contain the usual clay layer are an effective barrier against
infiltration of feedlot runoff.
7. Concentration in groundwater of dissolved solids derived
from High Plains cattle feedlots is restricted to the vicinity
of the point-source (feedlot). This is accountable to the
low total volume of infiltrate, plus dilution of the infil-
trate in the groundwater zone. Low total volume of infil-
trate is, in large part, due to (A) low rainfall, high runoff-
evaporation rates, (B) low permeability factors associated
with the feedlots, and (C) secondary precipitation in the
unsaturated zone. Around feedlots a significant dilution
factor is the usually large flow rate (natural and induced)
in the Ogallala relative to permeability rates between the
watertable and the surface. Groundwater dispersal rates
determined under existing field conditions show average values
ranging from 45 to 400 feet per year. Actual dispersal rates
are greatly dependent upon distribution and pumping rate
of producing wells at the site. Where a feedlot operation
uses large volumes of groundwater, significant quantities
of infiltrate that reach the saturated zone are recovered
by pumping.
8. Practical seepage rates determined under existing field
environments range from 2 to 20 feet/year. Rates of concen-
tration of NOj-N in the Ogallala Formation of the High Plains
approximate 0.07 to 0.3 p.p.m. NC^-N/year. Approximate values
for rate of concentration of chloride are 0.07 to 0.4 p.p.m.
Cl/year. Average values for rates of concentration of chlo-
ride and nitrate-nitrogen are about 0.17 p.p.m. per year.
Average rates of increase in conductance values for ground-
water beneath High Plains feedlots are 40-100 micromhos/cm
per year.
9. There are several feedlots in this study that have con-
tributed N03-N to levels approaching or exceeding recommended
limits (10 p.p.m. NC^-N). Some of the lots that have degraded
water quality approaching recommended limits are expected
to exceed such limits in the future. On the other hand,
some sites in the High Plains will probably never signifi-
cantly degrade groundwater quality, the reasons being slow
infiltration rates relative to groundwater dispersal rates,
recycling of infiltrated runoff, subsurface impermeability
at the site, and rapid dispersal of surface runoff^ No re-
gional degradation of the Ogallala groundwater is expected
in the foreseeable future, only degradation in specific
localized areas.
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RECOMMENDATIONS
1. Ion-balance studies are needed of nitrogen and other com-
mon ions associated with feedlot runoff. As already known,
the concentration of some ions, for example Ca, K, N0£, NH^,
Org-N, are not quantitatively correlative from ponded runoff
to the unsaturated zone to the groundwater zone. Imbalances
of nitrogen are in part attributable to nitrification-
denitrification reactions and volatilization of ammonia; Ca
and K reductions are attributable to cation exchange reactions
between plants-soils-bacteria and to chemical precipitation
by oxidation reactions and evaporation. Natural processes
operate to cause such desirable imbalances; thus, techniques
need to be investigated to enhance these desirable results.
2. An investigation is required to determine optimal rela-
tionships of seepage to return flow (pumping) under field
conditions. Some feedlots for all practical purposes should
show buildup of runoff in the groundwater zone yet the buildup
does not occur; quantitative relationships of seepage to re-
turn flow need to be evaluated. Slow seepage rates may be
acceptable for feedlots that use large volumes of groundwater.
3. Shallow-hole exploration (20-40 feet) of playas is needed
to better determine the geology and its relation to control
of seepage. New (pre-feedlot) and old playas should be in-
cluded to evaluate the effects of colloid-filtrate plugging.
4. Periodic evaluation of groundwater quality beneath selected
sites used in this study should be made on an annual basis.
It is recommended that water supply wells in the vicinity
of all feedlots be sampled annually for specific ion content
in groundwater.
5. In selecting future feedlot sites to minimize degradation
of groundwater it seems significant to pay attention to the
geographic location, type of "runoff system" and liquid-waste
handling procedures, composition and structure of near-surface
earth materials at the site, and pre-existing water quality
beneath the site.
Ideally, it would seem preferable to locate sites outside
areas with very sandy soil zones. This in fact has been the
trend in feedlot location, though probably unintentional.
The "migration" of feedlots has been northward on the Plains
to areas with less sandy soil than exists in the south, south-
west part of the Plains.
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The best "runoff system" should be a situation where long-
term' ponding does not occur. Water that is ponded should
be in an essentially impermeably bottomed reservoir. Many
High Plains playas serve this purpose if_ the natural clay
liner is not breached and the storage capacity of the imper-
meable (clay) part .of the playa is not exceeded. If the
natural clay liner of a playa is breached, the side-slopes
of the excavation as well as the bottom should be restored
to its original density. Clay layers in playas are lense-
shaped bodies that are thin toward the edges of the "ponding"
part of the playa; therefore, the "ponding" area of a playa
adjoins what can be relatively permeable material. Long-
term induced head due to "ponding", even in poorly permeable
zones, may eventually cause movement of liquid-waste to the
groundwater zone. Handling procedures for liquid waste may
be of considerable significance in reducing potential pollu-
tion hazards. Spreading of liquid waste increases the ulti-
mate destruction and rate of conversion of nitrogens to tol-
erable levels as well as serving to decrease concentrations
in localized areas.
Permeability data taken from cores of the subsurface unsatu-
rated zone (Ogallala Formation) and from near-surface soil
zones of feedlots indicate that the least permeable zones
are consistently at or near the surface. This is a result
of several factors some of which are inherently due to the
geologic development of the Ogallala and some due to second-
ary precipitation of dissolved solids in soil zones of feed-
lot runoff surfaces. Runoff slopes in time usually decrease
in permeability.
There are places in the High Plains where naturally .occurring
nitrate-nitrogen and other ions are in high concentration.
Obviously, in these geographic areas small additions of un-
desirable chemical compounds to the groundwater zone can
degrade water quality to an intolerable limit for household
or municipal use. The intolerable limit one speaks of is
dependent upon the intended usage of the water. Certainly
many industrial and agricultural applications of water have
much higher tolerable limits in terms of nitrate-nitrogen
and other ionic concentrations than water for household usage
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INTRODUCTION
Increasing concern within the last decade over possible con-
centration of nitrate and other ions in the saturated zone
beneath commercial cattle feedlots has warranted numerous
studies where feedlots proliferate. Fortuitously interrela-
ted factors of climate, soil, and groundwater, resulting in
high-yield feedgrain production, have led to development of
over one hundred major cattle feeding operations in the High
Plains of Texas. Commercial cattle feedlots have been in
existence in the Texas High Plains for 35 years, but increas-
ing concern due to asymtotic development within the 1960's
led to initiation of this and other studies.
The initial objectives of this study included (1) quantita-
tive estimates and distributive geometry of nitrogen (N03,
N02, NH4,- Org-N) and other chemiqal parameters (Ca, Mg, Na,
K, Cl, §64, pH, conductance) in groundwater below some major
feedlot operations, and (2) determination of relative rates
of movement of infiltrates from surface to the groundwater
zone under field conditions existing in the High Plains.
Initiation of the original project by the EPA led to incor-
poration of additional objectives supported by the Texas Water
Development Board, Texas Cattle Feeders Association, North
Plains Water District (Texas), and Texas Tech University.
The principal objectives incorporated into the total project,
by support of the aforementioned agencies, were to (3) deter-
mine the significance of subsurface distribution of dissolved
solids from feedlot runoff to the groundwater zone (Ogallala
aquifer), and to (4) evaluate what total geologic environment(s)
in the High Plains is (are) least conducive to infiltration
of feedlot runoff to the groundwater zone. Discussion, pres-
entation of data, and conclusions relative to objectives 1
and 2 are, primarily, herein reported. A separate publica-
tion-'- relative to objectives 3 and 4 is in preparation.
Study Sites
Eighty commercial cattle feedlots (locations, Figure 1) were
investigated to varying degrees for the total research pro-
gram. The 80 feedlots ranged from new to 35 years in estab-
lished age (distribution, Figure 2) with a one-time cattle
capacity of over one million head (load vs years established,
Figure 3).
be published by International Center for Arid and
Semi-Arid Land Studies, Texas Tech University, Lubbock, Texas.
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OKLAHOMA
^v
HUTCHINSON^1*
FIGURE 1—LOCATION OF CATTLE FEEDLOTS INVESTIGATED IN STUDY,
TEXAS HIGH PLAINS
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41950 51
52 53 54 55 56 57 58 59 I960 61 62 63 64 65 66 67 68 69 1970
YEAR FEEDLOTS ESTABLISHED
FIGURE 2--AGE DISTRIBUTION OF FEEDLOTS IN STUDY
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o
o
o
.iH
X!
E-"
a
oo pq
I
w
H
PH
ISO
165
150
135
120
105
90
75
60
45
30
15
0
10.3
10.0
t
L
! 6.7
3.3
15 10 5 0
AGE IN YEARS
t!950 51 52 53 54 55 56 57 58 59 I960 61 62 63 64 65 €6 67 68 69 1970
YEAR FEEDLOTS ESTABLISHED
FIGURE 3--APPROXIMATE AVERAGE CATTLE LOAD vs. YEAR FEEDLOT ESTABLISHED
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Twenty-two feedlots were drilled and/or cored to investigate
subsurface geology and chemistry of part of the unsaturated
zone. Five representative feedlots, each of which lies south
of the Canadian River, are herein described in detail.
Socio-economic implications inherent in such a volatile topic
as feedlots and potential groundwater pollution prohibit
detailed locations. The specific site locations are of but
academic interest; geologic environments and their relation
to the Texas High Plains geologic framework are the signifi-
cant factors. Accordingly, we have designated the sites
under the generality of field sites I thru V.
Field Methods
Holes were drilled with a commercially-owned mud-rotary rig
and with a mud-rotary rig of the Texas Water Development
Board. All coring was completed with the TWDB rig. Drilled
holes were reamed 12 3/4 inches in diameter to a depth of
50 feet and then completed to TD with an 8 3/4-inch bit.
All drilled holes were.set with slotted, 6-inch plastic casing
and cemented -to a depth of 50 feet. One-foot extensions
of casing above ground level were capped with a commercial
well seal. • Holes drilled and cored with the Water Develop-
ment Board rig were completed to TD with an 8 3/4-inch bit,
and set with slotted, 5-inch plastic casing, cemented to a
depth of 20-40 feet, and capped with.a commercial well seal.
Holes were completed below the watertable but not necessarily
to the base of the Ogallala Formation. Gamma and spontaneous
potential-resistivity logs were run by the U. S. Geological
Survey, Lubbock, Texas, on all drilled holes reported in this
phase of the project.
Four-inch diameter, two-foot long rotary cores of the Ogal-
lala Formation were taken with a double-walled core barrel
with a custom-designed sheet-metal liner to retain the core
upon removal from the barrel. Four-inch diameter push barrels
were used for cores of soil zones. Core samples collected
in the field for chemical analysis were retained below ground-
water temperatures with dry ice. The metal liners were sealed
with paraffin, the push cores sealed with plastic wrapping
and paraffin, and then shipped to the TWDB Materials Testing
Laboratory, Austin, Texas, for determination of plasticity
index, void ratio, porosity, permeability, size analysis,
and moisture content. Field and laboratory descriptions
of lithology were made according to the Unified Soil Classi-
fication System.
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Laboratory'Methods
Laboratory core analyses included determination of (1) in
situ unit weight and moisture content, (2) Atterberg Limits,
(3) shrinkage factors, (4) grain size analysis by sieving
and hydrometer, (5) specific gravity, and (6) vertical con-
stant head permeability. In addition to the above labora-
tory tests, void ratio, porosity, and degree of saturation
were calculated.
Details of techniques used to determine each of the afore-
mentioned parameters are available from the following sources
The in situ unit weight and moisture content test procedure
used is "Suspended Weight in Air and Water", as described
in U. S. Bureau of Reclamation Earth Manual, Designation
E-10, Part E, page 454.
The test procedure for determining Atterberg Limits was the
one-point hand method for liquid limit (LL), as described
in the Texas Highway Department Soil Manual, Test Method
Tex-104-E. The plastic limit (PL) and plasticity index (PI)
were measured according to ASTM Test Specification D-424;
shrinkage factors are described in ASTM Test Specification
D-427.
The grain-size analysis procedure used is described in ASTM
Test Specification D-422. Al-1 soils samples in which 5%
or more of the material passed the No.. 200 sieve were graded
by both sieving and hydrometer analysis.
The procedure used to determine the specific gravity of soil
is described in ASTM Test Specification D-854. Fifty-gram
samples were treated in a 500 ml flask; a vacuum pump was
used to remove entrapped air.
Constant head permeability tests were run on an undisturbed
core, trimmed to obtain parallel ends and uniform diameter.
The sample was then placed in a permeameter and saturated
under constant head. When uniform flow was obtained, the
quantity of water flow during a measured time was determined.
Permeability was calculated as shown.
thA
K = coefficient of permeability
Q = quantity of flow
L = core length
t = time elapsed
h = total head loss
A = core cross-sectional area
10
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Water-quality parameters determined include the nitrogen
family (NO,, N0£, Ntfy, Org-N), common ions (Cl, Ca, Mg, Na,
K, 504), pH and conductance.
Water-quality determinations were made using Orion specific
ion probes, a Technicon nitrogen autoanalyzer, and wet chem-
istry techniques; conductivity and pH values were measured
by meters. The wet chemistry analyses were performed in
accordance with procedures specified in Standard Methods
for Examination of Water and Wastewater. Duplication of
analytical techniques was employed in the examination of
many samples in order to provide a basis for correlation
of results obtained by different techniques.
Aliquots for core chemistry were taken by soaking and mechani-
cally mixing equal weights of sediment and distilled water.
The core extracts were analyzed in the same manner as the
water samples.
Nitrogen Cycle
A review of the nitrogen cycle is presented as prelude to
the discussion of feedlots and water quality. Nitrogen in
nature occurs as molecular nitrogen (N?); as organic nitro-
gen in urea, proteins, amino acids, and protein derivatives;
inorganic nitrite (N02), nitrate (N03), ammonia (Nt^), and
ammonium (NH^) ions; and as other less (quantitatively) im-
portant intermediate products.
All animals and plants contain nitrogen, and nitrogen also
exists in the earth's atmosphere, lithosphere", and hydrosphere
Inorganic physico-chemical reactions and inorganic-organic
reactions associated with plant-animal metabolic activity
serve as the "catalyst" whereby nitrogen in various forms
is cycled in nature. As a generality, the biological (in-
organic-organic) phase of the nitrogen cycle is graphically
represented.
\
ORG. M
FIXATION
j «
i
ATTER-* »-ORG
t
Kl —
I
\
i
1 1 -
r
A
* N2,02 ~
NITRIFICATION
> — »!*% ^«.
^REDUCTION
,J
N2
j
— »-N
J
,02
t
^FICATION
r
RECYCLE
11
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In the cycle, organic nitrogen is converted into inorganic
ammonia, nitrite, nitrate and to molecular nitrogen. Decom-
position of organic matter results in formation of organic
nitrogen and other products. Subsequently, organic nitrogen
is used as an energy source by bacteria and is converted to
ammonia. Large quantities of ammonia escape to the atmosphere
as a gas; other molecules of ammonia are oxidized under aerobic
conditions, as a bacterial energy source, to nitrite and ni-
trate. Nitrite and nitrate may further be converted to nitro-
gen gas.
Shortcuts and reversals exist in the aforementioned oxidative
process (See diagram). Under anaerobic conditions, nitrate
may be converted to nitrite and to nitrogen gas. To close
the cycle, some organisms are capable of assimilating nitro-
gen into cellular matter.
Significant differences in factors affecting the nitrogen
cycle exist between the environment of feedlots and that of
many freshwater systems. These factors are the organic-inor-
ganic load, predominance of bacterial activity over the ac-
tivity of algae, changing aerobic-anaerobic environments,
and the removal of runoff to the subsurface environment.
A Texas High Plains feedlot surface is an environment of al-
ternate wetting-drying, the organic and inorganic load exceeds
the capacity for degradation, the surface is aerobic (some-
times anaerobic at depth), and bacterial activity is high.
The runoff collection-system is heavily laden with organic-
inorganic matter, oxygen-deficient conditions often exist
at depth, and bacterial activity is high. In the unsaturated
subsurface, seepage results in removal of liquid from the
anaerobic conditions. The denitrification and reduction of
nitrate by bacteria account for relatively low concentrations
of nitrate in feedlot-runoff collection ponds. On the con-
trary, nitrification (oxidation) of organic nitrogen, nitrite
and ammonia to nitrate account in part for the accumulation
of nitrate in the unsaturated zone and groundwater zone be-
neath feedlots.
12
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DISCUSSION OF STUDY AREA
Observations on the relationships of cattle feedlot sites
to geomorphological-geological features and groundwater
quality in the Southern High Plains are presented, followed
by descriptions of representative field sites. Outlining
the geologic setting of High Plains cattle feedlots provides
the framework for evaluating relative rates of movement of
nitrate and other ions from the surface to the watertable,
and natural rates of dispersal in the groundwater zone under
existing field conditions.
Geomorphology-Geology
The High Plains is in the "Panhandle" of Texas and is the
southernmost extension of the Great Plains which borders
the east side of the Rocky Mountains. The High Plains is
bounded on the east and west by an erosional escarpment and
merges southward into the Edwards Plateau.
Only one major stream, the Canadian River, transgresses the
southern High Plains, but tributary drainage to the Red, Colo-
rado, and Brazos rivers originates in the region. Drainage
relative to cattle feedlots is localized principally within
the stream systems and in the ubiquitous closed-drainage pla-
yas that occur in the region. Semiarid climatic conditions
of low rainfall (±20 inches), large daily fluctuations in
temperature (±40°) , and high-wind conditions (5-35 mph) re-
sult in low values for long-term runoff and in periods of
rapid drying.
Most feedlots in the High Plains are located on stream drain-
age systems or playa systems. Approximately 40% of the feed-
lots considered in this study are located on streams, 45%
on playas, and 15% have no relation to the aforementioned
geomorphic features. These statistics are applicable to all
feedlots in the Texas High Plains. Of course, good drainage
is an economic asset and in most instances such benefits are
readily obtainable by proper geographic location.
High Plains streams have gradients ranging from about 10 feet/
mile to less than 5 feet/mile. Feedlot playas considered in
this study have a relief of from 5 to 45 feet of closed con-
tours. Feedpens located adjacent to stream channels and pla-
yas in Armstrong, Bailey, Castro, Lamb, Lubbock, Farmer and
parts of Deaf Smith counties (Figure 1) have drainage slopes
ranging from 2% to 5%; feedpens in Floyd, Hale, Gray, Potter,
Oldham and Moore counties have slopes ranging between 0.2%
and 2%. Few feedpen slopes of the High Plains exceed 5% in
value.
13
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The Ogallala Formation, the principal aquifer, surfaces the
Texas High Plains, along with a thin intermittent veneer of
unconsolidated Pleistocene sediments. The Ogallala is breached
to the-underlying Cretaceous System in some large playas (non
feedlot) and to the Triassic and Permian systems along the
Canadian River.
Soils distribution in the High Plains (Figure 4) (1, 2, 3)
has a significant relation to infiltration of surface water,
thus a relationship to infiltration of cattle feedlot runoff.
Rates of infiltration and total accumulation of dissolved
solids in groundwater are, in general, higher in "sandy soils"
and areas of "sand dunes" than in the tighter soil zones.
Total dissolved solids (TDS) and specific-ion maps^ (chloride,
nitrate) of areas in the southern High Plains where no feedlots
are located, indicate this relationship. A contributing factor
for the sandy soils, groundwater quality relationship is the
relatively rapid entrapment of surface water by loose surficial
material (sand) which prevents ready runoff, evaporation, and
even evapotranspiration due to low plant density. One should
add"that the significance of soils distribution in terms of
potential degradation of large volumes of groundwater is di-
minished when one considers the low total number of feedlots
(±20 in 1970) in the sandy soil zones of the High Plains.
Most surface materials on stream and playa feedlot slopes
consist of dense, fine-grained, semi-consolidated soils under-
lain by caliche. Feedlots located on Texas High Plains streams
have feedpens situated on slopes consisting of caliche and
thin soils, but in many the stream bottoms have breached the
caliche. Feedlots in headwater areas and tributaries of streams
have the usual caliche zone beneath the stream channel. Poorly
permeable, thin zones of clayey silt were found in stream
channels that breach the caliche; at most sites these zones
were underlain by thin layers of fine- to coarse-grained sand
and/or gravel. The clayey silt and sand-gravel valley fill
overlies the Ogallala Formation.
Vertical constant head permeability values determined for the
clay-silt sediments of channels are 10"^ to 10"^ cm/second.3
The underlying sand zones usually have vertical permeability
values of 10"' cm/sec, or larger. Most sediments that occupy
the floodplain of the channel consist of a near-surface zone
2
Derived from published and unpublished data of Texas
Water Development Board and High Plains Water District, and
by chemical analyses in Geoscience Department Water Quality
Lab, Texas Tech University. In preparation for publication.
31 X 10"6 cm/sec equals 1.034 ft/year.
14
-------
OKLAHOMA
LEGEND
| | FINE TEXTURED SOILS
SANDY SOILS
SAND DUNES
FIGURE 4--GENERALIZED SOIL TEXTURE MAP, TEXAS HIGH PLAINS
(After Carter, 1931; Lotspeich § Coover, 1962;
Lehman, Stewart § Mathers, 1970)
15
-------
of clay and clay-silt that is slowly permeable to impervious.
Vertical constant head permeability values determined for
floodplain sediments in this study range from 10~? cm/sec
to larger permeability values.
The "pond" of playas is surfaced by layers of clay, which
is underlain by layers of "lake-fill" sand and/or lenses of
clay-silt-sand. Playa "fills" up to 40 feet in thickness
were measured, and all are underlain by the Ogallala Forma-
tion. Vertical permeability values of playa lake clay are
10~6 to 10~8 cm/sec or lower in value (impermeable). Lithi-
fication of medium and coarse-grained clastic zones is notice-
ably absent beneath the "standing water area" in all types
of collection systems.
Surficial silt-clay mixtures surfacing feedpens and/or run-
off slopes exhibit secondary cementation in the form of root
fillings, vug and pore fillings, and veinlets. Below this
developed hardpan, soil densities are noticeably less. Per-
meability values typical of the hardpan surface of feedpens
and drainage slopes range from 10~4 to 10~? cm/second.
Caliche below playa and stream channel collection systems
is porous and permeable. Secondary solution of caliche is
evidenced by vugs, secondary cementation of fractures and
solution vugs, and by silt-clay filling in solution vugs and
voids.
The Ogallala Formation underlies the surficial material at
all feedlots considered in this study. In terms of infiltra-
tion, most laboratory determined permeability values in the
unsaturated zone range from 10"^ cm/sec to 10~6 cm/sec; the
larger permeability values of Ogallala sediments will permit
rapid percolation of water. However, minimum permeability
of near-surface material and minimum permeability values of
Ogallala sediments determine actual vertical transmissibility
rates.
Groundwater
Groundwater in the study area is ubiquitous within the Ogal-
lala Formation. Depth-to-water ranges from a minimum of 10
feet (parts of Tierra Blanca Draw) to depths of 250-300 feet.
Saturated thicknesses range from 30 feet to 300 feet in areas
investigated. Concentration of water-quality parameters in
this study varies significantly in the Ogallala aquifer within
short distances (few hundred feet), regionally from north to
south, and in some geographic localities from west to east.
16
-------
In the High Plains, nitrite, ammoniacal and organic nitrogen,
sodium, potassium, calcium, chloride, and total-dissolved-
sojids (IDS) are definitive parameters for collected feed-
lot runoff. Most feedlot runoff (ponded) ranges from less
than one hundred to several hundred p.p.m. of ammoniacal and
organic nitrogen, chloride, sodium, calcium, potassium, and
up to several thousand p.p.m. of IDS. These chemical parame-
ters invariably are more concentrated in collected runoff
than in Ogallala groundwater. Nitrite and nitrate-nitrogen
concentrations in feedlot runoff (ponded) range from less
than 10 p.p.m. to several tens-of-parts-per-million. Nitrite-
nitrogen is -consistently more concentrated in feedlot runoff
than in groundwater, but this relation is not always true
for nitrate-nitrogen.
There are areas in the southern High Plains, particularly
in sandy soil zones, where naturally occurring N03-N is higher
in "normal" Ogallala groundwater than in water beneath feed-
lots that show evidence of "seeping" to the watertable.
Thus, in order to relate groundwater quality to cattle feed-
lot runoff one must first establish the quality of water
in the Ogallala aquifer in the vicinity of a feedlot site
prior to time of establishment of the site in question.
Ionic concentrations in feedlot runoff are often difficult
to correlate with concentrations of specific ions in ground-
water derived from feedlot runoff. This is particularly
true for potassium. Rarely is there correlation of high
potassium concentrations in feedlot runoff with low potas-
sium concentrations consistent in Ogallala groundwater.
This is in part accountable by plant use of potassium, ad-
sorption by clay minerals, and use of potassium by organisms.
Nitrite-nitrogen, ammoniacal nitrogen and organic nitrogen
infiltrated from feedlot runoff also are not easily corre-
lated with the occurrence of these ions in groundwater.
Such imbalances are attributable to inorganic oxidation-
reduction reactions and/or to metabolic processes of organisms,
Chloride and conductivity values, and sometimes NOj-N, show
the most consistent correlation.
As noted previously, secon'dary precipitation of dissolved
solids is readily noticeable in the few feet of near-surface
material of feedlots and in parts of the unsaturated zone
of the Ogallala Formation. This is another cause of the
often observed common cation-anion imbalance between the
chemistry of cattle feedlot runoff and groundwater.
17
-------
INFILTRATION - GROUNDWATER
QUALITY RELATIONSHIPS
Theoretical consideration aside, particular attention was
given to field evaluation of factors that control seepage
and seepage rates. Cattle loading history in terms of years
and number of cattle was developed for 80 feedlot sites.
Other data for the sites include determining thickness of
the saturated and the unsaturated zones; feedpen slopes;
drainage basin, feedpen, collection system area-volume re-
lations; and type of collection system. Other practical mat-
ters of rainfall rates and periodicity, and balance studies
of amount and rate of runoff-evaporation-infiltration were
not determined directly. Distribution of nitrogen (N03,
N02, NH,, Org-N) and common chemical parameters (Ca, Mg,
Na, K, Cl, 804, pH, conductance) in groundwater beneath the
80 feedlots and their vicinity were determined. Also, near-
surface cores were taken from 22 feedlot sites (feedpens
and collection ponds) in the High Plains.
From a regional viewpoint, concentration of nitrate and other
dissolved solids in groundwater as a result of runoff from
feedlots is related to soils patterns. The southern part
of the southern High Plains and the western part of the North
Plains has a sandy soil cover (Figure 4, page 15), and the
feedlot water-quality data developed for this study Show
higher infiltrate concentrations in groundwater beneath the
sandy soil zones than in the hardland region. As noted pre-
viously, this observation concerning soil-infiltration re-
lationships .is confirmed, independent of this study, by Texas
Water Development Board annual observation well records and
by specific ion (N03, Cl) distribution maps of the southern
High Plains.
Local sediment distribution is significant also. Surface
sediments in High Plains playas are, almost invariably, es-
sentially impermeable (<10~6 cm/sec). Also, secondary depo-
sition in feedpens and on runoff slopes develops a near-
surface hardpan that retards infiltration. The unsaturated
portion of the Ogallala at few sites considered in this study
is sufficiently impervious t.o prevent some seepage of ponded
feedlot runoff if it penetrates the surfacing mantle; there-
fore, permeability of near-surface material is often the
essential controlling factor in infiltration.
No direct correlation between drainage slopes and groundwater
quality in the High Plains is apparent. As indicated pre-
viously, few slopes exceed about 5 percent, and within these
limits other overriding factors evidently are more signifi-
cant. The prime significance of feedlot slopes is to pre-
vent ponding which increases the probability of seepage.
18
-------
Ratios of collection-system area to area of drainage-basin
are in general unrelated directly to groundwater quality-
Possible exceptions to this observation are large ratios of
drainage-basin area to runoff-collection area of feedlots
located on stream channels, and small ratios of drainage basin
to runoff-collection area of feedlots located on playa sys-
tems. In many large drainage basins with through-flowing
streams into which feedlots empty, there has not been any
significant buildup of infiltrates beneath the feedlots.
Perhaps other unknown factors affect this relationship.
According to Lehman, Stewart and Mathers (3), playa collec-
tion systems that are small (volume) in relation to drainage
basin areas influence infiltration of impounded water. Com-
putation of drainage-basin area to playa-area ratios and their
correlation to groundwater quality do not confirm this. How-
ever, a study by Hauser (4) and permeability determinations
in this current study leads the writer to agree with Lehman
and others. One must conclude that small ratios of drainage
basin to playa volume are of some importance in preventing
collection and infiltration of runoff in the "overflow" parts
of the playas bordered by sandy soils. Hence, the pumping
of excess water out of playa collection systems is a justi-
fiable practice.
Cattle load and surface-area of feedpens may have some sig-
nificance to seepage and seepage rates, but they do not appear
to be independently related, to groundwater quality beneath
Texas High Plains cattle feedlots. Perhaps the interaction
with other factors may mask their correlation with ground-
water quality. A summary of the relationship of this and
other factors to quality of groundwater are enumerated in
Table I."
19
-------
TABLE I
RELATION OP FEEDLOT RUNOFF SEEPAGE FACTORS TO GROUNDWATER QUALITY,
TEXAS HIGH PLAINS
NJ
O
Factors
Geographic Location
Age of lot
Feedlot cattle load
Feedpen surface
Feedpen gradient
Stream gradient
Drainage area vs Feedpen area
Type o£ collection system
System capacity vs Drainage area
Collection-pond surficial material
Subsurface *lithology
Caliche "caprock"
Depth to water
Saturated thickness beneath lot
Relation
Significant; related to soils distribution, geomor-
phic and geologic control.
Significance interdependent on other factors. Related,
but old feedlots do not mean pollution.
Not considered significant for commercial feedlots .
Surficial material of most feedpens is poorly permea-
ble due to compaction and cementation.
Not correlative with groundwater quality.
No relation to groundwater quality.
Rarely significant; Only with very large ratios in
streams and small ratios in playas.
Significant; playa and non-ponding system away from
stream most desirable.
Not always significant. Local geology important.
Important; playa clay impermeable.
Minimum permeability significant in Ogallala.
Significance is questionable due to unpredictable
permeability.
Significant in some geographic locations.
Importance dependent in part on transmissibility of
Ogallala Formation.
-------
FIELD INFILTRATION RATES AND DISPERSAL
RATES IN GROUNDWATER
Infiltration and groundwater dispersal rates of feedlot run-
off are evaluated within the detailed geologic framework
of five selected field sites. In addition, concentration
of NOj-N, chloride, and conductance values in groundwater
are correlated with the ages of 80 feedlots (Locations,
Figure 1, p. 6) to further determine field rates of infil-
tration that exist in the Texas High Plains. The field sites,
designated I through V, are located in the central part of
the southern High Plains.
Field Site I. Distribution of observation wells at Site I
is shown in Figure 5. This feedlot is eleven years old and
has a one-time capacity of 7,000 head of cattle. Runoff
from this feedlot collects in a large shallow playa that
contains an open borehole which has been in existence for
two years; surface runoff moves by gravity flow into the
groundwater zone.
The Ogallala Formation crops out at the surface in the feed-
pens. The playa contains 20-25 feet of sediment consisting
of a near-surface clay and, underlying this, alternating
lenses of clay-silt and nodular caliche; a profile of sub-
surface' lithology of the Ogallala Formation at Field Site I
is shown in Figure 6, page 23.
Thirteen cores were taken for permeability determinations,
but most of the section is so loosely consolidated and fria-
ble that in situ permeability determinations were not always
possible. Constant head permeability values determined at
this site in the Ogallala range from 1.45 X 10"5 cm/sec to
5.5 X 10"3 cm/second. Certainly 10~5 cm/sec is near the
minimum permeability of the Ogallala at this site. The clay
layer of the playa is very slowly permeable to impermeable
(10"' cm/sec). Various hydrologic parameters of subsurface
material are shown in Figure 7, page 23.
Core chemistry (Table II) beneath the collection pond indi-
cates runoff has not infiltrated to the groundwater zone.
Water-quality data (Table III, p. 25) from well installations
(Well #5, #6, Figure 5) also indicate that seepage has not
occurred beneath the feedpens to the groundwater zone.
Laboratory determined minimum permeability values for the
Ogallala at this site are about 15 feet/year. Depth-to-water
beneath the feedpens is 120-130 feet, which theoretically
would permit seepage to the watertable within about 8-9 years.
Since runoff has not reached the watertable due to seepage,
21
-------
•~ WELL
-„,__ TOPOGRAPHIC
~34iS— CONTOUR
ROAD
CONTOUR INTERVAL s FEET
FIGURE 5--DISTRIBUTION OF OBSERVATION WELLS,
FIELD SITE I
22
-------
WELL 16
el. 3430
Elev.
3400-
3375-
3350-
3325-
3300-
3275-
FIGURE 6--GAMMA LOG PROFILES, FIELD SITE I
FEET GAMMA LOG
BELOW WELL 8
L.S.D.
0-
.25
RELATIVE
GRAIN SIZE
DISTRIBUTION
(mm.)
p%
K-cm. sect1
.005 .45 70 90 30 40 45 K>~2 IO~S Kf4 IO"6
—i ii ti i I i u_
ii ii
k k
80-
100-
i iii
RADIATION -
INCREASING
^GRAIN SIZE
INCREASING
VOID RATIO POROSITY
^PERMEABILITY
INCREASING
FIGURE 7--SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE I
23
-------
TABLE II--CORE CHEMISTRY, WELL #8, FIELD SITE I
FEET BELOW
L.S.D. N03-N N02-N An-N ORG-N CA MG CL SO/, IDS pH I MOIST
0 6.64 0.003 0 0.84 38 6 20 28 211 8.03 13
9 1.33 0.003 0 0.84 44 H 20 20 78 8.10 15
17 1.33 0.003 0 0.56 42 8 20 16 448 8.13 13
44 0.44 0.003 0 0.56 38 8 20 12 68 8.22 17
67 0.88 0.003 0 0.56 45 6 26 13 192 8.01 17
90 0.81 0.003 0 0.56 30 9 12 11 120 8.30 13
ALL CHEMICAL CONCENTRATION VALUES REPORTED AS DRY WEIGHT; ALL IONS IN P.P.M.
at Field Site I during its 11 years of existence, the con-
clusion is that near-surface permeabilities are the control-
ling factor in the extended seepage time.
The saturated zone of the Ogallala Formation is 180 feet in
thickness. The Triassic immediately underlying the Ogallala
is an aquiclude, as is usual in the High Plains. Flow direc-
tion in the Ogallala is normally toward the east but the
presence of the open borehole has resulted in a mound on
the watertable. The mound is recognizable for a radius of
approximately 800 feet in a southeast direction from Well #9.
The present -difference in head from epicenter to the south-
east edge of the mound is on the order of 10 feet. This
well is pumped intermittently; therefore, the geometry of
the mound varies with time.
Groundwater chemistry (Table III, page 25) was determined
from sampling of 19 observation wells. The real indicators
of runoff reaching the groundwater zone at this site are
the high N02-N and NH4-N values of Well #9. Distribution
of "above-normal" N03-N in groundwater (Figure 8) corresponds
to the geometry of the groundwater mound described previously.
Rate of dispersal of runoff-derived groundwater has averaged
400 feet/year. This field rate is reported under conditions
of periodic rainfall-injection and on a recovery-as-needed
basis.
Scalf, Hauser, McMillion, Dunlap and Keeley (5), and Schneider,
Jones and Wiese (6) report from short-term induced injection-
recovery studies of NOj movement in the Ogallala Formation
that rates of movement under injection exceed the 400 feet/
year value. Also, these investigators revealed that recovery
24
-------
TABLE III--GROUNDWATER CHEMISTRY, FIELD SITE I
WELL No.
1
2
3
1
5
6
7
8
9
10
11
12
13
11
15
16
17
18
19
N03-N
1,3
1,1
1,4
1.0
2.1
1.3
1.0
0.9
7.9
1.1
2.1
0.8
0.8
0.8
0.6
0.5
0.7
0.5
3.5
N02-N
0.000
0.009
0.001
0.003
0.000
0.100
0.003
0.600
6.300
0.006
*
0.006
0.003
0.003
0.015
*
*
*
0.003
AM-N
0.00
*
*
*
*
0.00
*
0.00
11.77
0.28
m »
*
*
*
*
*
*
*
*
ORG-N
0.00
*
0.22
0,12
*
0.00
*
3.60
7.00
0.00
*
*
0.11
0.28
*
*
*
*
0.28
CA
12
18
53
83
56
11
12
18
58
68
10
10
.78
/7
11
36
10
11
80
He
11
18
29
30
52
15
63
17
11
78
79
39
30
26
71
17
11
15
27
NA
31
33
31
29
78
20
28
16
15
20
29
27
36
*
25
31
11
25
*
K
8
10
9
9
7
8
8
8
12
11
11
7
10
•
11
10
10
10
*
CL
70
31
22
61
110
16
23
51
71
170
61
25
52
10
28
23
25
32
52
SO/,
60
110
7
26
100
10
*
10
10
10
*
10
21
20
*
*
*
*
25
COND.
735
617
855
685
765
680
660
600
735
1010
660
690
680
610
610
190
610
615
558
PH
7.3
7.5
7.3
7.8
7.3
7.2
7.1
7.5
7.3
7.1
7.3
7.3
7.8
7.8
7.3
7.1
7.3
7.3
7.9
ALL VALUES IN P.P.M. EXCEPT CONDUCTANCE AND pH, CONDUCTANCE IN MICROMHOS
25
-------
LEGEND
•3 WELL
—6— RRM. HOf-H
:^= ROAD
FIGURE 8--DISTRIBUTION OF NOs-N IN GROUNDWATER,
FIELD SITE I
26
-------
of injected NC>3 is related closely to volume of water recov-
ered during pumping. Even though very high concentrations
of dissolved solids in runoff have flowed to the groundwater
zone at this site, high concentrates do not exist at great
distances from the borehole. This relationship is due es-
sentially to volume recovery of high IDS concentrates near
the bore hole, and due to dilution away from the point source
of injection.
Field Site II. Location of observation wells of Field Site
II are shown in Figure 9. Site II is a 19-year feedlot with
a one-time cattle capacity of 8,000 head. A playa collects
runoff from the feedlot and, in periods of high rainfall,
runoff flows southwestward down an intermittent drainage
channel. Water stands in the playa except for relatively
long dry periods. Drainage slope of the feedpen is approxi-
mately one percent.
The Ogallala Formation crops out at the surface. The feed-
pen surface is soil covered, and below this lies a caliche
"caprock." The caliche is breached in the deepest part of
the playa. The playa fill consists of 5 feet of dense, im-
permeable clay below which lies 15 feet of clay-silt and
secondary nodular caliche. The lake fill overlies fine-grain,
clean sand of the Ogallala Formation that typically under-
lies the small playas in the High Plains (Figure 10). Con-
stant head permeability values of the unsaturated zone range
between 1.0 X 10"4 cm/sec to 4.7 X 10~3 cm/sec (Figure H).
Playa lake clay permeability is 10'~7 cm/sec, or less.
Surface material is the only impediment to seepage of feed-
lot runoff at this locality. Seepage occurs at this site
as indicated by core chemistry (Table IV) and degreee of
saturation (66-87%) above the watertable.
Field Site II has been in existence for 19 years; depth to
the watertable at this location averages 115 feet. Theoreti-
cally, average rates of seepage have exceeded 6.0 feet/year.
As stated, the minimum permeability of the Ogallala is 1.0
X 10'4 to 4.7 X 10~3 cm/sec (exceeds 100 ft/yr). In prac-
tical terms, average field seepage rates are controlled by
near-surface seepage rates; the actual rate is indeterminable.
An average 200 foot saturated zone occurs within the Ogallala
Formation in this area; the underlying Triassic serves as
an aquiclude. As is typical in the High Plains, groundwater
flow is to the southeast.
Groundwater-quality parameters (Table V) for this site were
established from 14 observation wells. Nitrate-nitrogen
values in groundwater range from 0.8 to 7.9 parts per million.
27
-------
FIGURE 9--DISTRIBUTION OF OBSERVATION WELLS,
FIELD SITE II
28
-------
Elev.
3325
3300- "-
3275-
3250-
3225-
FIGURE 10--GAMMA LOG PROFILES, FIELD SITE II
FEET
BELOW
L.S.D.
0-
20-
40-
60-
80-
100-
120-
GAMMA LOG
WELL 9
RELATIVE
GRAIN SIZE
DISTRIBUTION V8
(mm.)
.25 .005 .45 .60 .75
p% K-cm. secT1
31 35 40 I0~2 IO"3 I0~* IO"5
ill iii
t"
h-
RADIATION .
INCREASING
J3RAIN SIZE .,-.,,.
INCREASING V01D
III III
POROSITY -.PERMEABILITY
POROSITY INCREASING
FIGURE 11--SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE II
29
-------
TABLE IV--CORE CHEMISTRY, WELL #9, FIELD SITE II
FEET BELOW
L.S.D. N03-N N02-N An-N ORG-N CA KG NA K CL SO/j TDS pH % MOIST
0.0
4.5
6.5
9.5
12.0
18.0
25.0
46.0
61.0
73.0
83.0
94.0
114.0
374.20
1 co on
152.80
76.20
67.72
65.69
43.54
72.57
14.64
26.68
0
0
13.94
13.36
0
5.39
3 TO
.32
2.40
0.95
*
2.44
1.69
1.49
1.88
0.69
•1.07
1.23
1.51
1.06
114.60
9.40
37.54
20.23
8.94
8.94
0
0
0
0
0
0
0
10556.80
3476.00
531.50
227.60
123.70
301.40
130.30
1.29
184.27
128.50
15.74
35.58
149.41
32.65
*
108
68
44
72
84
60
120
84
64
60
128
68
*
41
29
34
22
46
34
46
39
32
36
46
68
*
*
42
30
38
30
28
30
12
32
32
14
12
*
*
86
71
78
43
38
36
28
26
26
32
34
*
383
220
170
220.
188
142
262
167
156
149
230
230
*
*
25
25
25
25
25
75
25
75
25
25
25
14700
It
1764
1176
1000
1176
1118
942
647
559
471
529
647
588
*
*
7.3
7.4
7.3
7.3
7.4
7.3
7.4
7.2
7.3
7.2
7.3
8.4
25.7
25.5
16.1
13.5
21.7
21.7
22.4
14.8
13.6
17.4
18.5
15.0
17.3
ALL CHEMICAL CONCENTRATION VALUES REPORTED AS DRY WEIGHT: ALL IONS IN P.P.M.
Nitrate-nitrogen values beneath this site are below the maxi-
mum value for the immediate area; therefore, NOg-N indepen-
dently is not .prima facie evidence of seepage. However, Ca,
Mg, Cl, and conductance values (Well #10, Table V) show that
seepage is detectable in groundwater below the feedlot site.
The relatively high chloride (Well #10) is not detectable
for more than 800-900 feet away from the epicenter of the
playa collection system (Figure 12). Assuming that runoff
could have reached the groundwater zone within the first year
the site was in operation, the minimum rate of dispersal in
groundwater has been approximately 45 feet/year. Permeability
values of the Ogallala indicate that minimum seepage time
would be 2-3 years; therefore, minimum dispersal rates would
be on the order of 55 feet/year.
Field Site III. Location of observation wells of Field Site
III are shown in Figure 13. This site is four years old with
a one-time cattle capacity of 4,000 head. The operation is
located on a stream, the stream channel serving as the col-
lection system for runoff. Runoff collects in a low, dredged-
out area of the channel, with the system overflowing during
periods of high rainfall. Drainage slope in the feedpens
is 3-4$, and the stream channel has a gradient of less than
ten degrees.
30
-------
TABLE V--GROUNDWATER CHEMISTRY, FIELD SITE II
WELL No.
1
2
3
1
5
6
7
8
9
10
11
12
13
11
15
N03-N
1,2
1.2
7.9
7.1
5.0
3.3
2.8
1.7
5.0
2.5
2.5
1.3
1.8
0.8
N02-N
*
*
*
0.060
0.009
0.006
0.015
0.031
0.020
0.100
0.009
0.006
*
0.000
AM-N
0.00
*
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
*
0.00
*
0.00
ORG-N
0.00
*
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
*
0.00
*
0.70
CA
16
16
16
16
16
51
15
51
71
10
10
51
22
10
MG
16
15
15
11
16
16
51
35
85
11
51
28
11
55
NA
21
37
10
21
21
28
32
33
21
11
22
80
10
82
K
10
10
11
10
10
13
9
11
10
10
10
11
10
8
CL
53
52
53
61
15
59
52
50
89
53
53
60
26
37
SOj,
10
10
10
10
10
10
10
10
50
10
10
10
*
100
COND.
6.17
650
588
617
676
618
627
599
1029
620
735
559
620
791
pH
7.1
7.1
7.1
7.3
7.1
7.3
7.2
7.3
7.3
7.3
7.1
7.2
7.7
7.2
ALL VALUES IN P.P.M. EXCEPT CONDUCTANCE AND pH. CONDUCTANCE IN MICROMHOS
9CoRE HOLE
31
-------
WELL
— 70—RRM. CHLORIDE
ROAD
0 20O 400600 BOO
FEET
FIGURE 12--DISTRIBUTION OF CHLORIDE IN GROUNDWATER,
FIELD SITE II
32
-------
WELL
TOPOGRAPHIC
CONTOUR
ROAD
— STREAM
CONTOUR INTERVAL 10 FEET
0 200. 400600
FEET
FIGURE 13--DISTRIBUTION OF OBSERVATION WELLS,
FIELD SITE III
33
-------
The Ogallala Formation crops out at the surface, with less
than 10' of Pleistocene "cover sand" and soil overlying the
Ogallala caliche "caprock." The caliche is within the feed-
pens but is breached in the low part of the stream channel.
Subsurface lithology (Figure 14) consists of zones of clay,
silt, clay-silt mixtures, and zones of fine to medium-grain
sand typical of the upper part of the Ogallala Formation.
Constant head permeability values in the unsaturated zone
of the Ogallala at the site range from 1.9 X 10~5 cm/sec to
1.39 X 10~2 cm/sec (Figure 14). There are no essentially
impervious stratigraphic units detectable between the surface
and wat.ertable.
FIGURE 15--SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE III
GAMMA LOG
t&ft" WELL 20
0-
20-
40-
60-
8O-
RELATIVE
GRAIN SIZE
DISTRIBUTION
(mm.)
r
Vs p% K-cm. see?'
005 .56 .70 .80 35 40 45 Iff2 IO"3 IO"4 KJ5
^RADIATION
INCREASING
GRAIN SIZE
INCREASING
VOID RATIO
POROSITY
^.PERMEABILITY.
INCREASING
Percentage saturation values of effective pore space of 75-85%
in several cores indicate that seepage does take place. Also,
core chemistry (Table VI) indicates a N03-N profile of 170
p.p.m. near the surface to 11 p.p.m. at a depth of 80 feet.
The rate of initial seepage probably is less than horizontal
flow rates in the saturated zone, as evidenced by the lack
of a groundwater mound beneath the collection pond. The depth
of water at this 4-year-old site ranges from 60-90 feet.
Seepage has reached the groundwater zone; therefore, the mini-
mum average field seepage rate is on the order of 15-23 feet/
year. Minimum permeability values determined in the laboratory
are 20 feet/year.
34
-------
Elev.
3225-.
3200-
3175-
3150
3125
WELL 18
el. 3233
WELL 25
el. 3235
Elev.
3225-
3200-
3175-
3150-
3HAUE.
SHALE,
SAND,
SANDY
SHALE
FIGURE 14--GAMMA LOG PROFILES, FIELD SITE III
35
-------
TABLE VI--CORE CHEMISTRY, WELL #20, FIELD SITE III
FEET BELOW
L.S.D. N03-N N02-M ORG-N K Ci_ % MOIST
2
6
18
21
28
36
37
45
54
68
80
170
68
22
22
22
45
45
50
11
44
11
0,80
0,92
0,44
0,92
0,96
0,52
0,48
0,52
0.76
0,88
0,96
585
85
102
94
23
46
95
51
16
45
212
400
60
40
40
40
40
120
40
40
60
120
567
549
461
461
372
390
355
390
319
337
408
14,3
15,2
14.7
18,3
19,8
16.8
18,1
14,9
16,3
17,0
10.1
ALL CHEMICAL CONCENTRATION VALUES REPORTED AS DRY WEIGHT; ALL IONS IN P.P.M,
The saturated zone in the vicinity of Site III is within the
Ogallala Formation and the underlying Cretaceous limestone.
Saturated thickness is 100 feet and, within this zone, flow
direction is to the east.
Water-quality parameters determined from samples from 28 ob-
servation wells in the area are shown in Table VII. N03-N
values in the vicinity range from 0.7 to 16.7 parts per million,
"Normal" background N03-N values approximate a range of 0.7
to 7.1 parts per million. This is the range in values in
the area west of the feedlot and up-dip on the watertable.
Abnormally high N03-N values (distribution, Figure 16) exist
near the feedlot and below the floodplain that exists north
of the feedlot. The floodplain has been under cultivation
and fertilization for many years and some of the N03-N in
the groundwater is attributed to this practice. With ground-
water flow to the east, if the feedlot were the principal
source of N03-N, the influent nitrogen would be expected to
have reached Well #23 (Location, Figure 13) before or by the
time water was degraded in wells numbered 22, 24, and 25.
Wells #23 and #24 are more apt to represent distance of move-
ment, which is on the order of a few hundred feet, with an
average rate of 100 feet/year.
36
-------
TABLE VII--GROUNDWATER CHEMISTRY, FIELD SITE III
WELL No.
1
2
3
1
5
6
7
8
9
10
11
12
13
11
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
N03-N
1.1
7.1
2.6
1.2
5.5
1.1
15.7
15.7
15.1
7.9
5.6
1.0
5.8
5.0
3.9
6.7
11.9
16.7
13.5
*
11.7
11.7
0.9
5.0
10.8
5.0
0.7
3.9
3.1
N02-N
*
0.160
0.009
0.100
0.020
0.006
0.600
0.530
0.030
0.130
0.009
0.003
*
*
0.010
0.009
0.020
0.060
0.210
•
0.009
0.009
0.000
0.070
0.012
0,010
0.003
0.010
0.001
AM-N
*
0.28
*
0.28
0.00
0.81
0.00
0.00
0.56
*
0.00
0.00
0.00
0.00
0.81
0.00
0.00
*
0.56
•
0.00
0.00
0.00
*
0.00
0.00
0.28
0.81
0.00
ORG-H
*
2.23
0.81
1.02
0.83
0.00
0.10
0.10
2.11
1.52
0.00
0.10
*
0.00
1.51
0.00
0.18
0.10
0.00
*
0.10
0.10
*
0.81
0.10
0.11
*
*
0.00
CA
65
91
88
50
60
70
58
50
50
50
51
58
60
82
51
51
50
51
61
*
53
50
18
50
18
58
76
90
11
Me
27
77
H
50
50
58
39
36
51
57
25
26
51
22
51
25
52
55
62
*
28
52
35
69
11
56
60
77
19
NA
51
78
*
59
62
67
59
56
65
57
61
57
78
72
56
59
65
65
57
*
60
63
60
62
58
61
71
78
61
K CL SO,, COND. pH
9 15 * 705 7.1
16 25 75 1323 7.2
150 86 692 7.6
13 85 100 882 7.1
13 113 50 911 7.3
17 117 150 1058 7.3
11 16 10 765 7.1
13 32 10 617 7.2
12 50 52 882 7.3
21 61 80 613 7.3
17 60 10 1058 7.2
16 67 10 735 7.3
18 121 10 911 7.3
22 112 80 853 7.1
13 103 50 882 7.1
17 82 10 821 7.2
13 71 100 1100 7.1
12 58 * 1010 7.3
15 57 10 617 7.1
* * * * *
17 50 821 7.1
16 59 75 821 7.3
15 69 «5 618 7.1
21 92 80 658 7.2
12 57 100 706 7.3
11 30 100 1069 7,1
17 138 100 1058 7.2
15 138 125 1176 7.2
12 59 280 730 7.1
ALL VALUES IN P.P.M. EXCEPT CONDUCTANCE AND pH. CONDUCTANCE IN MICROMHOS
20CoRE HOLE
37
-------
\ \ \ \
FIGURE 16--DISTRIBUTION OF N03-N IN GROUNDWATER,
FIELD SITE III
38
-------
Field Site IV. Field Site IV observation wells are shown
in Figure 17. This location has been in use for 16 years
with a one-time capacity of 4,500 cattle. Runoff from this
site collects in a playa.
The Ogallala Formation crops out at the surface. Playa
sediments are 10 feet in thickne.ss, including a 4-foot upper
clay layer. The clay layer of the playa is relatively im-
permeable at the cored location (Well #7). Typical subsur-
face lithologies of the Ogallala are depicted in Figure 18.
Nine cores were taken in the Ogallala Formation beneath the
pond, and representative analyses indicate a constant head
permeability range in value of 5.27 X 10"^ cm/sec to 1.03
X 10-3 cm/sec (Figure 19).
Core chemistry (Table VIII) indicates that N03 has penetrated
to a depth of at least 46 feet, and other ions show a decreas-
ing trend to the watertable. Calcium, potassium, and conduc-
tivity values decrease sharply below 11 feet. Based on N03-N,
the field seepage rate has been no more than 3-4 feet/year.
TABLE VIII--CORE CHEMISTRY, WELL #7, FIELD SITE IV
FEET BELOW
L.S.D.'
2.5
6
11
30
16
57
68
88
110
N03-N
0.00
12.15
13.01
*
13.33
0.00
0.00
0.00
0.00
N02-N
1.10
1.59
1.25
*
1.18
1.68
1.29
1.13
1.01
AM-N
0.00
0.00
0.00
*
0.00
0.00
0.00
0.00
0.00
ORG-N
113
33
67
*
0
171
32
65
32
CA
*
81
88
31
32
28
21
16
21
MG
*
26
26
13
31
36
18
16
16
NA
*
68
38
60
8
11
18
33
32
K
*
30
11
27
22
17
11
10
10
CL
*
230
212
117
78
78
69
53
62
S01
*
80
10
10
80
10
10
10
80
TDS
*
1058
1000
617
588
529
112
617
382
pH
*
7.3
7.1
7.1
7.1
7.3
7.1
7.1
7.5
% MOIST
11.2
9.3
13.1
*
15.3
18.9
15.0
15.2
15.2
ALL CHEMICAL CONCENTRATION VALUES REPORTED AS DRY WEIGHT; ALL IONS IN P.P.M.
39
-------
FIGURE 17--DISTRIBUTION OF OBSERVATION WELLS,
FIELD SITE IV
40
-------
WELL 7
el. 3392
Elev.
3375-
3350-
3325-
3300-
3325-
FIGUKE 18--GAMMA LOG PROFILES, FIELD SITE IV
FEET GAMMA LOG
BELOW WELL 7
L.S.D.
0-
ao-
40-
60-
80-
RADIATION^
INCREASING
RELATIVE
GRAIN SIZE
DISTRIBUTION
(mm.)
.25 .005 JS
^GRAIN SIZE v
vs
0 75 1.0 3
1 i
1
1 1
010 RATIO F
p% K-cm. sec
5 45 50 I0~s I0~4 1C
ii ii
m^^m •^••^B
ii ii
npneiTV PERMEABILI1
I
r5
•y
INCREASING
INCREASING
FIGURE 19--SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE IV
41
-------
The saturated zone of the Ogallala Formation is 200 feet
in thickness. Within this zone, 21 wells were used to col-
lect water samples for chemical analyses (Table IX). In
terms of NC^-N, the range in normal background N03-N is 0.7
p.p.m. to 4.7 parts per million. Seepage has not reached
the groundwater at this site.
Field Site V. The surface layout of Site V is shown in Fig-
ure 20. This site has been in operation for 3-5 years and
has a one-time capacity of 17,000 head of cattle. The ca-
pacity was 4,000 cattle in the 1940 Ts, 7-10,000. head in the
1950's, and 15-17,000 head of cattle in the 1960's. Runoff
collects in a playa, and the playa water in turn is pumped
outside the basin for purposes of irrigation. Feedpen drain-
age slopes average 1-2 percent.
The Ogallala Formation crops out in the feedpens. A caliche
layer exists near the surface, and below this is a typical
Ogallala section (Figure 21). The playa is filled with sedi-
ment to a depth of about 20 feet.
Constant head permeability values within the Ogallala range
from essentially non-pervious to 3.2 X 10~3 cm/sec (Figure
22). The geologic section at this site is less permeable
than any of the other sites described in the report.
Core chemistry (Well #9, Table X, p. 46) indicates that per-
haps NO 3 has not reached the water table beneath the pond;
however, groundwater chemistry (Table XI, Wells 4, 5, 9,
11, 13) indicates some seepage of N03 has occurred. The
depth to water is 110-115 feet; thus, the 35-year-old-site
exhibits an average minimum field rate of infiltration of
about 3 feet/year. This falls within the range of laboratory
determined permeability values for the site.
The saturated zone at the site is within the Ogallala Forma-
tion, and groundwater chemistry was determined from 16 obs.er-
vation wells penetrating this zone. N03-N values (distribu-
tion, Figure 23) range from 0.8 to 8.4 parts per million;
N03-N values exceeding 5 p.p.m. are above normal at the site.
Rate of dispersal of NOs-N in groundwater has been less than
100 ft/year.
Other Sites
A minimum of five and a maximum of 25 groundwater samples from
beneath each of 75 additional feedlots were chemically ana-
lyzed. Distributive groundwater geometry of NO-j-N (and other
ions) derived from feedlot runoff was determinable from about
15 to 20 of these sites. The maximum detectable distance of
42
-------
TABLE IX--GROUNDWATER CHEMISTRY, FIELD SITE IV
WELL No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
20
21
22
NOj-N
0.8
1.4
2.3
2.5
2.8
1,7
1.60
2.1
1.9
0.7
3.5
1.4
3.6
1.43
2.1
4.1
2.5
4.7
4.2
2.1
1.7
N02-N
*
*
*
0.120
0.300
0.006
0.030
0.006
*
*
0.200
»
0.060
0.010
0.006
0.006
0.560
0.240
0.160
0.760
*
AM-N
*
*
*
0
0
0
0
0
*
*
1.96
»
0
0
*
*
0.28
0
0
0
1.96
ORG-N
*
*
*
0
0
0
2.0
0
*
*
0
#
0
4.87
*
*
0
0
0
0
0
CA
44
34
45
44
48
50
54
46
43
38
56
45
40
64
50
43
46
42
40
44
48
KG
39
55
48
39
38
55
57
34
37
57
38
35
36
52
55
47
40
45
43
35
34
NA
32
31
37
31
33
29
11
36
35
35
41
54
50
21
30
35
41
31
34
33
40
K
10
11
9
9
9
11
11
9
11
10
8
9
8
8
10
11
9
9
7
9
8
CL
27
44
34
57
46
39
43
41
39
21
39
64
50
41
43
47
53
50
57
43
43
SO,,
*
140
*
40
40
40
20
40
*
*
40
*
40
20
*
*
40
40
40
40
40
COND.
720
- 700
550
647
588
647
663
647
740
540
588
640
588
595
676
650
559
559
588
588
559
pH
7.3
7.4
7.6
7.2
7.4
7.2
7.6
7.2
7.8
7.5
7.2
7.3
7.4
7.5
*
7.5
7.4
7.4
7.4
7.4
7.3
ALL VALUES IN P.P.M. EXCEPT CONDUCTANCE AND pH, CONDUCTANCE IN MICROMHOS X
43
-------
WELL
~irm— TOPOGRAPHIC
3710 CONTOUR
ROAD
CONTOUR INTERVAL 10 FEET
FIGURE 20--DISTRIBUTION OF OBSERVATION WELLS,
FIELD SITE V
44
-------
Elev.
3725-
3700-
3675-
3650-
3625-
3600-
S":TLSHALE CLAYEY SAND
SAND
FEET
BELOW
L.S.D.
0-
20-
40-
60-
80-
120-
140-
FIGURE 21--GAMMA LOG PROFILES, FIELD SITE V
6AMMA LOG
WELL 9
RADIATION
INCREASING
.25
RELATIVE
GRAIN SIZE
DISTRIBUTION
(mm.)
p%
^GRAIN SIZE
INCREASING
I I i
VOID RATIO POROSITY
K-cm. secT1
Iff4 iff5 Iff6 iff7
PERMEABILITY
INCREASING
FIGURE 22--SUBSURFACE HYDROLOGIC PARAMETERS, FIELD SITE V
45 __
-------
TABLE X--CORE CHEMISTRY, WELL #9, FIELD SITE V
FEET BELOW N03-N N02-N AM-N ORG-N CA MG NA K CL S0a IDS pH % MOIST
L.S.D. 4
3.5
9
17
22
29
35
13
58
72
84
98
110
21.16
11.97
0.00
0.00
0.00
25.31
0.00
12.49
73.62
12.59
12. SI
0.00
0.99
1.15
0.80
1.00
1.04
0.98
1.03
1.06
0.61
1.16
1.09
1.13
0.00
0.00
7.80
0.00
0.00
0.00
0.00
0.31
0.00
0.00
0.00
0.33
13.98
46.30
22.68
78.41
65.00
5.35
46.12
17.11
0.00
17.47
97.33
47.84
54
52
40
40
34
36
36
50
38
48
30
26
26
16
24
27
21
22
18
23
19
19
10
13
25
13
38
50
48
50
31
24
12
18
13
15
11
7
9
18
9
10
11
13
9
10
6
7
106
96
71
115
124
113
99
82
64
64
57
60
40
40
80
40
60
60
40
160
80
120
60
60
412
588
529
529
588
588
529
559
441
471
324
353
7.4
7.4
7.4
7.5
7.2
7.1
7.2
7.2
7.3
7.2
7.3
7.3
6.6
5.7
*
11.8
15.2
14.2
11.1
9.6
8.0
10 3
11.9
14.8
ALL CHEMICAL CONCENTRATION VALUES REPORTED AS DRY WEIGHT; ALL IONS IN P.P.M.
travel of NOj-N in the groundwater zone was on the order
of 1500 feet. It is concluded, dissolved solids concentrated
in Ogallala groundwater from point-sources such as cattle
feedlots usually are restricted to the vicinity of the site.
To determine relative field rates of seepage on a regional
basis, several chemical parameters were evaluated in terms
of ages of feedlots. The values used to derive the graph
shown in Figure 24 represent maximum values of N03-N in ground-
water beneath each of 80 feedlots. Each feedlot used repre-
sents 5 to 25 groundwater analyses, and the high and low
maxima for each year represent 5 to 70 determinations of
N03-N. The dashed line shows the base level for"NC>3-N be-
neath Texas High Plains feedlots. This base level has not
been corrected for "normal" background levels in the Ogal
lala before establishment of the feedlots; therefore, the
base level for feedlot N03-N contribution is less than shown.
The base line shows a general increasing trend in N03-N con-
centration with age. The upper (solid) line of Figure 24
46
-------
TABLE XI--GROUNDWATER CHEMISTRY, FIELD SITE V
WELL No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
NOrN
1.1
2.3
2.4
5.7
5.0
3.6
1,4
1.0
6.4
1.0
8.4
1.0
5.2
2.7
0.8
4.17
N02-N
*
*
*
*
»
0.000
*
0.003
0.003
0.003
0.012
*
0.099
*
*
*
AM-N
*
*
*
*
*
0
*
0
0
0
0
0
0
0
0
0
CA
56
64
80
54
64
67
65
64
65
56
65
60
74
68
92
68
MG
52
37
36
60
61
59
37
62
60
52
52
33
80
29
47
40
NA
59
39
72
60
60
64
65
57
59
58
57
44
52
85
52
52
K
9
12
13
15
10
12
14
15
16
8
11
10
15
11
16
10
CL
78
195
124
72
85
85
125
85
95
85
50
82
174
124
195
103
so/,
145
40
40
140
150
*
*
*
*
40
*
40
134
40
40
40
COND.
880
1150
882
890
790
706
995
706
805
735
794
706
1215
1000
941
735
PH
7.3
7.2
7.2
7.3
7.5
7.6
7.4
*
7.3
7.4
7.5
7.2
7.4
7.2
7.2
7.2
ALL VALUES IN P.P.M. EXCEPT CONDUCTANCE AND pH. CONDUCTANCE IN MICROMHOS
47
-------
\
\
2 \
LEGEND
—s— RPM. NO,-N
ROAD
FIGURE 23--DISTRIBUTION OF N03-N IN GROUNDWATER,
FIELD SITE V
48
-------
represents the highest maximum level of N03-N found in all
lots for each year shown. As with the base line, it has not
been corrected for "normal" background N03-N. The upper line
tends toward considerable variation in age concentration re-
lationships and indicates that, disregarding age, some lots
contribute N03-N to the groundwater zone of the High Plains.
The average slope of the N03-N base line (dashed) is about
0.17 p.p.m. NC>3-N per year. The maximum slope value is 0.3
p.p.m. N03-N per year. These approximated rates represent
point-sources beneath all feedlots in the study and have no
significance for a specific geographic location. In conclu-
sion, these values approximate a regional rate of concentra-
tion of NC>3-N in Ogallala groundwater from cattle feedlots .
Additional profiles are shown for chloride (Figure 25) and
conductivity values (Figure 26) beneath the 80 feedlots .
The profiles show slopes of 0.07-0.40 p.p.m. Cl/year and an
increase in conductivity of 40-100 micromhos/cm/year,
respectively. These data also reflect field infiltration
rates as described for NO^-N.
49
-------
en
o
LOWEST MAXIMUM NO,-N
£1950
1955
I960
YEAR FEEDLOT ESTABLISHED
1965
1970
FIGURE 24--AGE OF FEEDLOTS INVESTIGATED vs. RANGE IN MAXIMUM NO,-N
-CONCENTRATION IN GROUNDWATER 3
-------
Cn
2SI3
\2
II
O
x 10
5
Q.
£ 9
d
z p
o 8
o
ai _
Q 7
o:
o
-J c
x 6
o
E 4
LJ
1 3
DC
2
I
HIGHEST MAX. Cl
LOWEST MAX. Cl
J I
«I950
J I I I I I I I
I I
1955
I960
YEAR FEEDLOT ESTABLISHED
1965
1970
FIGURE 25--AGE OF FEEDLOTS INVESTIGATED ZS. RANGE Ifl MAXIMUM CHLORIDE
CONCENTRATION OF GROUNDWATER
-------
in
(x|00)
28
HIGHEST MAX. COND.
LOWEST MAX. COND.
a I960
1955
I960
YEAR FEEDLOT ESTABLISHED
1965
1970
•FIGURE 26--AGE OF FEEDLOTS INVESTIGATED ys. RANGE IN MAXIMUM
CONDUCTANCE OF GROUNDWATER
-------
ACKNOWLEDGMENTS
William D. Miller, Professor and Chairman, Geosciences
Department, Texas Tech University, served as principal
investigator and assumes sole responsibility for the scien-
tific accuracy of the results herein reported.
Special acknowledgment is due the feedlot owners and managers
of the Texas High Plains who generously allowed us full use
of their facilities, often for many days at a time. Their
generosity is especially gratifying due to the public outcry
over potential pollution by feedlots.
The Projects Division and Materials Testing Laboratory of
the Texas Water Development Board were major contributors
to the total project. The core-drill crew from the Projects
Division, TWDB, included James W. Sansom, Jr., Geologists
and Crew Chief; Keith Keppel and Leon Byrd, Geologists; Lewis
Barnes, Chief Driller, Hugo Walker and Lynn Jorgensen, Assis-
tant Drillers. Materials Testing Laboratory personnel who
contributed to the field work and who performed laboratory
investigations of cores are Messrs. Paul Pasemann, Ronnie
Weddell, Joe Gates, Steve Gifford, all Engineering Techni-
cians, and Mike Howard, Technician, Structure Section.
Messrs. G. S. Sawyer, Projects Division Director, J. E. Hunt,
Chief, Materials Testing Lab, and James 0. Rodgers, Engineer,
were instrumental in the planning phase of the project.
Appreciation is also extended to Mr. C. R. Baskin, Chief
Engineer, Mr. Seth Burnitt, Water Quality, and Mr. R. C.
Peckham, Head, Ground Water division, Texas Water Develop-
ment Board, for their assistance with planning and implemen-
tation of portions of the project.
Recognition is given for financial support of the project
to the Texas Cattle Feeders Association, Mr. Lloyd Bergsma,
Executive Director, and the TCFA Board of Directors, Mr. Bob
Carter, President.
The North Plains Water Di-strict (Texas), J. W. Buchanan,
Manager, contributed financial support, and SP-logging equip-
ment for logging in the North Plains.
Messrs. Dennis Bell, Chief Research Assistant, and John Buchanan,
David Normand and Bill Watson, Student Research Assistants,
Geoscience Department, Texas Tech University, contributed
to the field and laboratory investigations.
53
-------
Mr. Clyde Wilson, Acting Project Chief, Bill Sandeen-, Physi-
cal Science Technologist, and Jim Smith, Hydrologist, U. S.
Geological Survey, Lubbock, Texas, performed the well logging
reported in this study.
The initiation and major support of the project by the En-
vironmental Protection Agency, Ada, Oklahoma, and the sup-
port by the Project Director, Mr. Marion R. Scalf, are grate-
fully appreciated.
54
-------
REFERENCES CITED
1. Carter, W. T., "The Soils of Texas," Texas Agricultural
Experiment Station, Bull 431, (1931).
2. Lotspeich, F. B., and Coover, J. R., "Soil Forming Fac-
tors on the Llano Estacado: Parent Material, Time and
Topography," Texas Journal Science, Vol. XIV, No. 1,
(1962) .
3. Lehman, 0. R., Steward, B. A., and Mathers, A. C., "Seep-
age of Feedyard Runoff Water Impounded in Playas," Texas
A§M - Texas Agricultural Experiment Station, MP-944, pp
1-7 (1970) .
4. Hauser, V. L., "Hydrology, Conservation, and Management
of Runoff Water in Playas on the Southern High Plains,"
USDA Conservation Res. Report, No. 8 (1966).
5. Scalf, M. R,, Hauser, V. L., McMillion, L. G., Dunlap,
W. J., and Keeley, J. W., "Fate of DDT and Nitrate in
Groundwater," USDI, FWPCA, R. S. Kerr Water Research
Center, (1968).
6. Schneider, A. D., Jones, 0. R., and Wiese, A. F-, "Pollu-
tion Research in Recharging the Ogallala Aquifer Through
Well.s," Ogallala Aquifer Symposium, ICASALS, Texas Tech
University, (1970).
55
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1
5
Accession Number
2
Organization
Geosciences
Stibjet-t Field St. Group
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Department
Texas Tech University
Title
INFILTRATION RATES AND GROUNDWATER QUALITY BENEATH CATTLE
FEEDLOTS, TEXAS HIGH PLAINS
10
Authors)
William D. Miller
Geoscience Department
Texas Tech University
Lubbock, Texas 79410
16
Project Designation
EPA Project #16060EGS
21
Note
22
Citation
23
Descriptors (Starred First)
Groundwater, nitrates*, feedlot runoff*, infiltration*
25
Identifiers (Starred First)
nitrates*, feedlot runoff, infiltration
field and laboratory studies o± tive teediots were conducted
to determine field seepage rates and distributive geometry of infiltrated
runoff. Practical field seepage rates at these sites ranged from 2 to 20 feet/
year.
Nitrogen (NO,, N02, NH4, Org-N) and common chemical parameters (Ca, Mg, Na,
K, Cl, 804, TDS, pH, and conductance) were determined in cores and groundwater
samples; based on groundwater analyses from 80 Texas High Plains feedlots,
rates of concentration of N03-N and Cl in groundwater beneath feedlots range
from 0.07 to 0.4 p.p.m. per year, and average 0.17 p.p.m. per year.
Laboratory determined constant head vertical permeability of cores from 22
feedlot sites revealed a range in values of 10"2 to 10~" cm/sec for Ogallala
sediments, 10~4 .to 10'7 cm/sec for near-surface material of floodplains and
feedpen-runoff surfaces, and values of 10'6 to-10'8 cm/sec for playa clay.
Factors related to runoff-infiltration were correlated with groundwater
quality, and it was determined that local surficial material and regional soils
patterns are closely related to quality of groundwater beneath feedlots.
Direct correlation of water quality does not exist with feedpen-runoff slope,
cattle load, and surface-area ratios of drainage basin to collection system.
27
Abstre
wTlliam D. Miller I
Institution
Texas Tech University
WR: 102 (REV. JULY 19S9I
WRSIC
SEND TO: WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 20240
« OPO: 1969-359
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