The chemical character of the ground water in Lyon County is shown by the analyses of samples of water from 33 wells given in parts per million in Table 4. Factors for converting parts per million of mineral constituents to equivalents per million are given in Table 5. These water samples were collected from the principal water-bearing formations and from different parts of the county as evenly as possible. Table 4 includes analyses of three public water supplies. The samples of water were analyzed by Howard A. Stoltenberg, Chemist, in the Water and Sewage Laboratory of the Kansas State Board of Health.
Table 5--Factors for converting parts per million of mineral constituents to equivalents per million.
|Cation||Conversion Factor||Anion||Conversion Factor|
The analyses of three water samples taken from successively deeper water-bearing beds in a well drilled at the Kansas Soya Products Company plant at the east edge of Emporia show the progressively higher mineralization that occurs with depth. The figures given in Table 6 represent composite samples of water from the aquifers penetrated by the well at the depth the water sample was collected. Samples were collected at the three levels at which considerable amounts of water entered the well. The analyses clearly show the progressively higher amount of dissolved mineral matter with increasing depth.
Table 6--Analyses of ground water taken from three principal water-producing zones at depths of 380, 600, and 865 feet at the Kansas Soya Products Company well, NE SW NW NW sec. 14, T. 18 S., R. 11 E. (Dissolved constituents in parts per million. Analyzed by Russell T. Runnels. Fresh surface water cased off. Sample collected from this level when well had been drilled to this depth or slightly deeper and bailed rapidly several times.
|Depth and Chief Geologic Source|
|380 ft, Calhoun sh||600 ft, Kanwaka sh||865 ft, Tonganoxie ss|
|Undetermined difference, chiefly bicarbonates||448||605||2,200|
|pH at 21°C||7.38||7.03||6.37|
Although large amounts of water are available from deep wells penetrating Pennsylvanian and older sediments (Fig. 2) the water is too highly mineralized for most uses.
When water is evaporated, the residue consists mainly of the dissolved mineral constituents and usually a little water of crystallization. Water containing less than 500 parts per million of dissolved solids generally is satisfactory for domestic use, except for difficulties resulting from its hardness or occasional excessive iron content. Water containing more than 1,000 parts per million may include enough of certain constituents to produce a noticeable taste or to make the water unsuitable in some other respect. The amount of dissolved solids in 33 samples of ground water from Lyon County ranged from 323 to 2,251 parts per million (Table 7).
Table 7--Dissolved solids in water samples from wells in Lyon County.
|Dissolved Solids, parts per million||Number of Samples|
|300 or less||0|
Hardness of water is the property that generally receives the most attention and in washing is recognized by the quantity of soap required to produce lather. Calcium and magnesium cause virtually all the hardness of ordinary water and are the active agents in the formation of the greater part of the scale formed in steam boilers and other vessels in which water is heated or evaporated.
In addition to the total hardness, the table of analyses shows the carbonate hardness and the noncarbonate hardness. The carbonate hardness, sometimes called temporary hardness, can be removed almost entirely by boiling. The noncarbonate hardness is due to the presence of sulfates or chlorides of calcium and magnesium; it cannot be removed by boiling and is sometimes called permanent hardness. So far as their use with soap is concerned, there is no difference.
Water having a hardness of less than 50 parts per million generally is rated as soft, and treatment for the removal of hardness is not necessary under ordinary circumstances. Hardness between 50 and 150 parts per million increases the consumption of soap, but does not seriously interfere with the use of water for most purposes. Hardness above 150 parts per million can be noticed by anyone, and if the hardness is 200 or 300 parts per million, the water commonly is softened for household use or cisterns installed to collect soft rain water. Where municipal water supplies are softened, the hardness is generally reduced to 60 or 80 parts per million. The further softening of a public water supply generally is not deemed worth the additional cost.
The hardness of 33 samples of ground water collected in Lyon County ranged from 266 to 1,166 parts per million (Table 8).
Table 8--Hardness of water samples from wells in Lyon County.
|Hardness, parts per million||Number of Samples|
|200 or less||0|
Next to hardness, iron is the constituent of natural waters that in general receives the most attention. The quantity of iron in ground water may differ greatly from place to place, even in water from the same formation. If a water contains much more than 0.1 part per million of iron, the excess may precipitate as a reddish sediment. Iron, if present in sufficient quantity to give a disagreeable taste or stain cooking utensils, may be removed from most water by simple aeration and filtration or the addition of lime or some other substance.
The iron content of 33 samples of ground water collected in Lyon County ranged from 0.05 to 9.9 parts per million (Table 9).
Table 9--Iron content of water samples from wells in Lyon County.
|Iron, parts per million||Number of Samples|
|Less than 0.1||7|
|More than 3.0||2|
The quantity of fluoride present in natural water is generally much less than the quantity of other constituents, but the fluoride content of water to be used by children should be known. The dental defect known as mottled enamel may appear on the teeth of children who drink water containing excessive amounts of fluoride during the period of formation of their teeth. Water containing 1.7 to 1.8 parts per million of fluoride is likely to produce mottled enamel in about half the children continuously using such water, although the percentage distribution would be largely of the very mild and mild types (Dean, 1936). Contents of fluoride up to 1.5 parts per million are believed to be beneficial in inhibiting tooth decay.
The fluoride content of the 33 samples of ground water collected in Lyon County ranged from 0.1 to 0.7 part per million.
The discovery in 1945 that nitrate in water can cause cyanosis, or oxygen starvation, of infants gave increased significance to the nitrate content of natural water (Metzler and Stoltenberg, 1950). A concentration of 90 parts per million of nitrate as NO3 in drinking water is considered by the Kansas State Board of Health as being dangerous to infants, and some authorities recommend that water containing more than 45 parts per million should not be used for formula preparation. Cyanosis is not produced in older children or adults by these concentrations of nitrate.
The relation of nitrate content to well construction, ground-water level, geologic formation, bacterial activity of soils, seasonal variations, and other factors is not yet clear. Observations show that shallow dug wells are generally more susceptible to nitrate contamination than are deeper drilled wells. Nitrate concentrations seem to be highest in the winter season and lowest during the growing season of late spring and summer (Metzler and Stoltenberg, 1950, p. 202).
More than one-half of the 33 water samples analyzed contained more than 45 parts per million of nitrate (NO3) and one-third contained 90 parts per million or more. The nitrate content of the 33 samples ranged from 1.3 to 407 parts per million (Table 4).
Sulfate (SO4) in ground water is derived chiefly from gypsum and the oxidation of marcasite and pyrite. Sulfate (SO4) occurring in ground water as magnesium sulfate (Epsom salts) and sodium sulfate (Glauber's salts), in excess of about 500 parts per million may have a laxative effect on persons not accustomed to drinking water containing large amounts of sulfate.
Chloride (Cl) is dissolved in small quantities from rock materials, from connate waters in the sediments, or in some instances may come from sewage. Chloride has little effect on the suitability of water for ordinary use unless the quantity is enough to give the taste of salt (300 parts per million or more). Waters high in chloride are very corrosive.
The water analyses shown in Table 4 show only the amounts of dissolved mineral matter and do not indicate the sanitary quality of the water. However, abnormal amounts of dissolved mineral matter, such as nitrate or chloride, may indicate pollution.
A dug well is more likely to become contaminated than a properly constructed drilled well, generally because the opening at the top of a dug well is not adequately covered and generally is not effectively protected from surface water. A drilled well is protected generally by the casing, but many are not properly sealed at the top. A well should not be located near possible sources of pollution such as barnyards, privies, and cesspools.
Kansas Geological Survey, Lyon County Geohydrology
Web version Sept. 2001. Original publication date March 1953.
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