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Causes Of Localized Copper Corrosion In Drinking Water Supplies, R. A. Sims, R. W. Raible May 1983

Causes Of Localized Copper Corrosion In Drinking Water Supplies, R. A. Sims, R. W. Raible

Arkansas Water Resources Center Technical Reports

Excessive amounts of copper have been observed in drinking water at certain installations on Lake DeGray and at isolated locations in the Arkadelphia area of Arkansas. A study of these installations was conducted to determine the source of the copper contamination. The supply water was very low in copper and therefore dissolution of the copper plumbing caused by low water pH and long residence times was determined to be the most probable source.

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Evaluation And Accessing Of Data For A Water Resources Simulator, Richard C. Peralta, Roberto Arce, Timothy Skergan Mar 1983

Evaluation And Accessing Of Data For A Water Resources Simulator, Richard C. Peralta, Roberto Arce, Timothy Skergan

Arkansas Water Resources Center Technical Reports

This report evaluates the availability of data needed to use a groundwater simulation model for real time conjunctive water management in the Arkansas Grand Prairie. It is assumed that the goal of such management is to protect existing groundwater rights by maintaining water levels so that wells do not go dry, even in time of drought. Sufficient hydrogeologic data exists to use the simulation model to predict the effect of known pumping rates on groundwater levels. Developing an optimal set of "target" levels and annually managing pumping to achieve those levels requires additional data: fall groundwater levels, degree of connection …

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Expansion Potential For Irrigation Within The Mississippi Delta Region, Robert N. Shulstad, Ralph D. May, Jon Mark Erstine, Blake N. Phillips, Billy E. Herrington Jr. Mar 1983

Expansion Potential For Irrigation Within The Mississippi Delta Region, Robert N. Shulstad, Ralph D. May, Jon Mark Erstine, Blake N. Phillips, Billy E. Herrington Jr.

Arkansas Water Resources Center Technical Reports

17.6 million acres, or 73 percent, of the Mississippi Delta Region is currently cropland and possesses the physical characteristics of slope, texture and soil type which are recommended for irrigation. Economic feasibility of expanding irrigation by flood, furrow and center pivot methods were examined under 24 scenarios representing two sets of crop prices, yield levels, production costs, opportunity costs and six crop rotations. Irrigation was economically feasible for 56 to 100 percent of the cropland across all scenarios. Approximately 88 percent of the cropland can be economically irrigated with flood or furrow in its present form, 8 percent yield highest …

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The Costs And Benefits Of Soil Erosion Control In The North Lake Chicot Watershed, Robert N. Shulstad, C. Tim Osborn, Alan D. Mcqueen Mar 1983

The Costs And Benefits Of Soil Erosion Control In The North Lake Chicot Watershed, Robert N. Shulstad, C. Tim Osborn, Alan D. Mcqueen

Arkansas Water Resources Center Technical Reports

Lake Chicot is divided by a levee into two basins, the high quality northern basin and the extremely polluted southern basin. Water quality in the northern basin of Lake Chicot is diminishing due to soil erosion. Costs for alternative control programs for the seventeen fare, 11,470 acre northern watershed were estimated. Twenty-nine combinations of rotations and best management practices were evaluated. Soil loss can be reduced almost 25 percent from 4.2 tons per acre to 3.2 tons per acre, while increasing net returns to farmers from $83.94 per acre to $107.28 per acre by altering present cropping patterns. A prohibition …

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Nutrients And Acid In The Rain And Dry Fallout At Fayetteville, Arkansas (1980-1982), George H. Wagner, Kenneth F. Steele Mar 1983

Nutrients And Acid In The Rain And Dry Fallout At Fayetteville, Arkansas (1980-1982), George H. Wagner, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

Wet and dry fallout at Fayetteville, Arkansas have been collected separately and analyzed since April, 1980. The precipitation-weighted-average pH for two yearly periods of rainfall were 4.72 (6/80-5/81) and 4.75 (6/81-5/82). This corresponds to a concentration of the acid ion, H+, of about 18 parts per billion (ppb). Pure water in equilibrium with the CO2 of the air would have a pH of 5.65 (2.2 ppb of H+). The range of pH during this two year period was 3.86-7.74(140-0 ppb H+) for the rainfall. Aqueous extracts of the dry fallout were always in the 6.75-7.87 pH range, i.e., neutral to …

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Monitoring Of Groundwater Levels For Real-Time Conjunctive Water Management, Richard C. Peralta, Vince Mazure, Paul Dutram Mar 1983

Monitoring Of Groundwater Levels For Real-Time Conjunctive Water Management, Richard C. Peralta, Vince Mazure, Paul Dutram

Arkansas Water Resources Center Technical Reports

Water users in the Arkansas Grand Prairie wish to maintain sufficient groundwater levels to: insure adequate groundwater reserves for time of drought, protect themselves from litigation caused by wells going dry, and insure a sustained yield. Achievement of these goals requires regular measurement of groundwater levels. Review of monitoring practice and technology indicates that spring and fall measurements taken over the entire area using steel tape and acoustic device is preferred for most long range planning. Continuous monitoring is indicated for critical parts of the region where saturated thicknesses are small. Desirable attributes of a data collection/transmission system for such …

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A Survey Of Soils Irrigated With Arkansas River Water, John T. Gilmour, H. D. Scott, R. E. Baser Mar 1983

A Survey Of Soils Irrigated With Arkansas River Water, John T. Gilmour, H. D. Scott, R. E. Baser

Arkansas Water Resources Center Technical Reports

Interest in the use of Arkansas River water for irrigation has increased recently as land adjacent to the river is converted to crop production and river water is considered as an alternative to depleted underground supplies. Since the Arkansas River can contain elevated concentrations of sodium chloride, this study was designed to determine if soil conditions adverse to crop growth were developing where river water has been used. The impact of river water on sites where river water was used as either the sole source for up to 3 years or as a supplement to another surface source for up …

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The Effects Of Forest Harvest On Water Quality And Aquatic Life (Phase I), Edmond J. Bacon Mar 1983

The Effects Of Forest Harvest On Water Quality And Aquatic Life (Phase I), Edmond J. Bacon

Arkansas Water Resources Center Technical Reports

A long term study on the effects of clearcut forest harvest and regeneration was conducted in a representative watershed of the Ouachita National Forest. Fourteen water quality parameters were analyzed to characterize baseline water quality. Water quality was classified as excellent. A total of 350 quantitative benthic samples and 15 ultraviolet light trap samples yielded 173 species of macroinvertebrates. Mean densities of macroinvertebrates ranged from 4,800/m2 to 23,040/m2 and averaged 12,499/m2 in the upper Little Missouri River. Twenty-two quantitative collections of fishes were made at representative riffles and pools. The average biomass estimates for riffles and pools were 5.69 kg/ha …

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Early Pennsylvanian Conodont-Ammonoid Biostratigraphy And The Witts Springs Problem, North-Central Arkansas, Mary Ann Eccher, Daniel J. Murdaugh, Wildon D. Hawkins Jan 1983

Early Pennsylvanian Conodont-Ammonoid Biostratigraphy And The Witts Springs Problem, North-Central Arkansas, Mary Ann Eccher, Daniel J. Murdaugh, Wildon D. Hawkins

Journal of the Arkansas Academy of Science

The Witts Springs Formation was proposed as a lithostratigraphic unit in north-central Arkansas to include the interval from a horizon equivalent to the base of the Prairie Grove Member, Hale Formation to the top of the Bloyd Formation, of the type Morrowan Series, northwestern Arkansas. The top of the Witts Springs Formation was regarded as being unconformably succeeded by the middle Pennsylvanian Atoka Formation. Recent investigation of this unit in its type area has shown that the presumed Atokan Sandstone is actually a unit confined to the Bloyd Formation. Thus, the type section of the Witts Springs in Searcy County, …

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67th Annual Meeting, 1983. Secretary's Report And Financial Statement, Academy Editors Jan 1983

67th Annual Meeting, 1983. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Computer Pattern Recognition Of Action Potentials, Ronald S. Remmel Jan 1983

Computer Pattern Recognition Of Action Potentials, Ronald S. Remmel

Journal of the Arkansas Academy of Science

A general method of pattern recognition was applied to the problem of recognizing extracellularly-recorded neuronal action potentials in the presence of noise and other pulses. A PDP1 1/23 performed the calculations. There were four stages: 1.) A bandpass filter attenuated noises; 2.) the data input program digitized the signal every 55 μsec. If the signal exceeded a threshold, 12 samples of the signal and the time were written onto the disk; 3.) the pulse discriminating program recognized an action potential by fitting the 12 points with this function: v(t) = (a + bt + ct² ) exp(-t/Ƭ). For each pulse …

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Flat Plate Solar Thermal Collectors: A Comparison Of Efficiencies Of Various Collector Configurations, Rudolph J. Eichenberger Jan 1983

Flat Plate Solar Thermal Collectors: A Comparison Of Efficiencies Of Various Collector Configurations, Rudolph J. Eichenberger

Journal of the Arkansas Academy of Science

No abstract provided.

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Microcomputer-Assisted Colorimetric Determination Of Iron, A. M. Hoyt Jr. Jan 1983

Microcomputer-Assisted Colorimetric Determination Of Iron, A. M. Hoyt Jr.

Journal of the Arkansas Academy of Science

No abstract provided.

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1983

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock Jan 1983

Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock

Journal of the Arkansas Academy of Science

Recently there has been much emphasis placed on the importance of leaf detritus processing to the energetics of stream invertebrates. This study was designed primarily to assess the effects of municipal effluent on the ability of a stream community to utilize leaf detritus, and secondarily to evaluate the extent of the pollution of the White River by the Fayetteville, Arkansas, effluent discharge. Physical and chemical water quality and benthos were sampled periodically at one station upstream and two stations downstream from the discharge, and in the Richland Creek tributary. Processing of leaf detritus was also studied at each site using …

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Proceedings Of The Arkansas Academy Of Science - Volume 37 1983, Academy Editors Jan 1983

Proceedings Of The Arkansas Academy Of Science - Volume 37 1983, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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The Application Of Laser Intracavity Absorption Detector To Gas Chromatography Of Trace Organic Pollutants In Water, Robert B. Green Dec 1982

The Application Of Laser Intracavity Absorption Detector To Gas Chromatography Of Trace Organic Pollutants In Water, Robert B. Green

Arkansas Water Resources Center Technical Reports

A helium-neon (HeNe) laser operating simultaneously at 3.39 um (infrared) and 0.63 um (visible) has been used as a selective detector for hydrocarbons in the effluent of a gas chromatograph. The infrared and visible laser transitions originate at the same energy level and are competitive. When a hydrocarbon enters the laser's resonant cavity, the 3.39 um energy is absorbed due to the C-H stretching vibration and the visible emission is enhanced. The visible laser emission is monitored with a photodiode as a quantitative measure of the concentration of the absorbing molecule. The minimum detectable concentration for propane using the double-beam …

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A Faunal And Seasonal Study Of The Aquatic Insects In Two Water Ecosystems In South Arkansas: Degray Reservoir And The Upper Cadda River, Robert T. Allen Oct 1982

A Faunal And Seasonal Study Of The Aquatic Insects In Two Water Ecosystems In South Arkansas: Degray Reservoir And The Upper Cadda River, Robert T. Allen

Arkansas Water Resources Center Technical Reports

The impounding of the lower Caddo River to create DeGray Reservoir radically changed the water habitats in that portion of the Caddo River. A number of new and different habitats were created by the lake. The objective of this study was to determine what, if any, differences existed between the aquatic insect biotas of DeGray Reservoir and the upper Caddo River. Four collecting stations along the shore of DeGray Reservoir and four stations along the upper Caddo River were selected as sampling sites. Collections were made at one month (March, April, Oct., Nov.) intervals or at two week intervals (May, …

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Effects Of Water On The Fate Of Herbicides In Irrigated Soils, Terry L. Lavy Aug 1982

Effects Of Water On The Fate Of Herbicides In Irrigated Soils, Terry L. Lavy

Arkansas Water Resources Center Technical Reports

The wide use of soil-applied herbicides necessitates an understanding of their fate in soil if we are to use them in the most beneficial manner. All herbicides have some degree of water solubility and the field performance of many are dependent on ample, timely availability of soil moisture. It is important that different aspects of soil-herbicide-water interactions be thoroughly investigated. An excess use of water for irrigation purposes can result in the downward movement of herbicides in the soil profile. Subsoils are less adsorptive and a decreased degradation potential exists when herbicides move below the top 15 cm. In sandy …

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Atrazine Degradation, Sorption And Bioconcentration In Water Systems, Duane C. Wolf, Ramon L. Jackson Aug 1982

Atrazine Degradation, Sorption And Bioconcentration In Water Systems, Duane C. Wolf, Ramon L. Jackson

Arkansas Water Resources Center Technical Reports

The herbicide atrazine is used extensively to control broadleaf and grass weeds in such crops as sorghum and corn. A small portion of the atrazine may be lost from the area of application by surface runoff and could enter a stream or lake. The objective of this study was to evaluate atrazine degradation, sorption, and bioconcentration in watersediment systems. The results indicated that sediments with lower pH values and higher organic matter levels adsorbed higher levels of atrazine than sediments with neutral pH values and lower organic matter levels. Microbial decomposition of the herbicide was slow under the conditions of …

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Proceedings Of The Arkansas Academy Of Science - Volume 36 1982, Academy Editors Jan 1982

Proceedings Of The Arkansas Academy Of Science - Volume 36 1982, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Leaf Detritus Processing In An Ozark Cave Stream, Arthur V. Brown, Mark D. Schram Jan 1982

Leaf Detritus Processing In An Ozark Cave Stream, Arthur V. Brown, Mark D. Schram

Journal of the Arkansas Academy of Science

Detritus processing rates and mechanisms were investigated in an Ozark cave stream using post oak (Quercus stellata) leaf packs. The 5 g leaf packs lost ca. 30% of their dry weight within 84 days, resulting in a calculated K value of 0.05. This was an unexpectedly high rate of utilization. Diversity of invertebrates associated with the leaf packs was very low. Stygobromus ozarkensis (Amphipoda) was the only shredder. The two isopods, Caecidotea stiladactyla and Lirceus sp. were the only collectors observed other than a single species of oligochaete worm. Our data indicated that leaf detritus processing rates are virtually independent …

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Reconnaissance Of The Bedrock Aquifers And Groundwater Chemistry Of Crawford, Franklin, And Sebastian Counties, Arkansas, Samuel R. Rothermel, Wyndal M. Robison, Julie L. Wanslow, James R. Musgrove, Daryll Saulsberry, Albert E. Ogden Jan 1982

Reconnaissance Of The Bedrock Aquifers And Groundwater Chemistry Of Crawford, Franklin, And Sebastian Counties, Arkansas, Samuel R. Rothermel, Wyndal M. Robison, Julie L. Wanslow, James R. Musgrove, Daryll Saulsberry, Albert E. Ogden

Journal of the Arkansas Academy of Science

A ground water reconnaissance of Crawford, Franklin, and Sebastian counties was performed utilizing 122 wells having drillers' logs from bedrock aquifers. North of the Arkansas River, essentially all bedrock wells produce from the Atoka Formation. There are many low producing aquifers within the Atoka with a range in yield of 0.1 to 55 gpm, but having a median yield of only 2 gpm. Well depths range from 18 to 248 feet with a median of 122 feet. More water is generally obtained from the shale/siltstone aquifers than the sandstones due to more bedding-plane partings and more closely spaced fractures. Greater …

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Preliminary Investigation Of Ground-Water Occurrence In The Atoka Formation Of Pope And Faulkner Counties, Arkansas, Wyndal M. Goodman, Albert E. Ogden Jan 1982

Preliminary Investigation Of Ground-Water Occurrence In The Atoka Formation Of Pope And Faulkner Counties, Arkansas, Wyndal M. Goodman, Albert E. Ogden

Journal of the Arkansas Academy of Science

One hundred and twelve wells having drillers' logs were studied in Pope and Faulkner counties. Sixty-six of the wells produced water from shales and siltstones of the Atoka Formation while 46 produced from interbedded Atoka sandstones. Drillers' estimated well yields ranged from 1 to 100 gpm, but the median yield was only 9 gpm. Well depths ranged from 30 to 337 feet with a median depth of 100 feet. Ground-water is usually obtained from a series of low-producing confined aquifers of low artesian pressure. Pressure head and production were shown, statistically (a = .01), to decrease with increasing well depth. …

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Physiological Studies Of Heat Stress Acclimation During A Specific Exercise Regimen, Leland F. Morgans, Alan M. Johnson Jan 1982

Physiological Studies Of Heat Stress Acclimation During A Specific Exercise Regimen, Leland F. Morgans, Alan M. Johnson

Journal of the Arkansas Academy of Science

Eleven subjects were used to determine if the exercise regimen of racquetball could be used as a heat stress acclimator. Core temperature, skin temperature, sweat production, and weight loss were recorded during a racquetball match. Skin and core temperatures were determined by using thermistors. Sweat was collected with modified stress electrodes. Weight loss was recorded by comparing nude weights at the beginning and end of a match. The results indicated that an hour of strenuous racquetball play caused a significant increase in core temperature with subsequent sweating which resulted in a significant decrease in skin temperature and weight loss. The …

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Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche Jan 1982

Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche

Journal of the Arkansas Academy of Science

No abstract provided.

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Reconnaissance Of Ground-Water Resources Of Stone And Independence Counties, Arkansas, Albert E. Ogden, James R. Musgrove, Lisa Milligan Jan 1982

Reconnaissance Of Ground-Water Resources Of Stone And Independence Counties, Arkansas, Albert E. Ogden, James R. Musgrove, Lisa Milligan

Journal of the Arkansas Academy of Science

No abstract provided.

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1982

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Sr/Mg Ratios Of Pennsylvanian Limestone Units In Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry Jan 1982

Sr/Mg Ratios Of Pennsylvanian Limestone Units In Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry

Journal of the Arkansas Academy of Science

No abstract provided.

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A Salt And Water Balance Model For A Silt Loam Soil Cropped To Rice And Soybean, J. T. Gilmour, J. A. Ferguson, B. R. Wells Dec 1981

A Salt And Water Balance Model For A Silt Loam Soil Cropped To Rice And Soybean, J. T. Gilmour, J. A. Ferguson, B. R. Wells

Arkansas Water Resources Center Technical Reports

A computer model was developed which described salt and water balances for a silt loam soil common to the Grand Praire physiographic region of Arkansas. A ten year period of weather data (1966-75) was used as input data for two divergent cases in regard to salt accumulation. Case one was a rice-soybean rotation with soybean irrigated, while case two was a rice-soybean-soybean rotation with soybean not irrigated. Salts considered were calcium, magnesium, sodium, sulfate and chloride as well as the precipitate, calcium carbonate. Where soybeans were not irrigated less evapotranspiration, more infiltration and less runoff were observed during the fallow …

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