Surveying Boron and Naturally Soft Groundwater with a Computer Database.Abstract The health department of Ingham County, Michigan Ingham County is a county in the U.S. state of Michigan. The 2000 census recorded its population at 279,320; a 2006 estimate placed the population at 276,898. The county seat is Mason6. Lansing, the state capital of Michigan, is also within the county. , has developed an ongoing program for evaluating and monitoring groundwater, the primary source of drinking water drinking water supply of water available to animals for drinking supplied via nipples, in troughs, dams, ponds and larger natural water sources; an insufficient supply leads to dehydration; it can be the source of infection, e.g. leptospirosis, salmonellosis, or of poisoning, e.g. in the area. In this undertaking, computerized mapping and database programs have been important tools. An example of how these tools work is provided by a case in which computer analysis helped identify potential concerns with boron boron (bōr`ŏn) [New Gr. from borax], chemical element; symbol B; at. no. 5; at. wt. 10.81; m.p. about 2,300°C;; sublimation point about 2,550°C;; sp. gr. 2.3 at 25°C;; valence +3. levels in some Ingham County water wells. Groundwater in Ingham County has been characterized as "hard," with the exception of naturally "soft" groundwater in one area of bedrock water wells. The naturally soft groundwater also has been characterized as having above-normal levels of boron--in excess of 1.0 parts per million parts per million mg/kg or ml/l; see ppm. . A computer mapping program and a water quality database were used to delineate the area of naturally soft groundwater. A review of well construction records indicated that wells in the soft-water area had more shale shale, sedimentary rock formed by the consolidation of mud or clay, having the property of splitting into thin layers parallel to its bedding planes. Shale tends to be fissile, i.e., it tends to split along planar surfaces between the layers of stratified rock. bedrock than hard-water wells. A statistical analysis confirmed the correlation between high levels of boron in groundwater and a higher percentage of shale bedrock in sampled wells. A correlation also was found between water hardness and sodium-to-boron ratios in groundwater. The levels of boron in the soft-water wells are of concern since the U.S. Environmental Protection Agency Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise pollution, and radiation and to ensure the safe handling and has issued a long-term health advisory for boron at 0.9 parts per million in drinking water. The computerized mapping and database programs were instrumental in studying this public health issue and could assist in many other projects related to the evaluation and monitoring of groundwater resources. Introduction Computers have become a tool as common in the workplace as paper and pencils. Many environmental health agencies have converted typical office records and tiles to computer systems. Information related to groundwater resources is one example of this trend. Groundwater information now can be filed and managed by computer programs or databases that are able to interface with computer software programs or provide information to those programs for analysis. A computerized groundwater database should include well construction and water chemistry data. Essential information includes * an accurate way of locating each site, * a description of the rock and soil material in which each well has been installed, * chemical data reflecting well water quality, * data on water quantity, and * groundwater elevation information. Once this kind of information has been collected in the computer, specialized software programs can provide a variety of analyses and reports. The reports and analyses can help with land use planning
Land use planning is the term used for a branch of public policy which encompasses various disciplines which seek to order and regulate the use of land in an efficient and ethical way. issues, cleanup of groundwater pollution, assessing the availability of drinking water for municipal systems, and the provision of general water quality information for a geographic area. The information also can be used to assess the exposure of the general public to possible contaminants in the drinking-water resource. In Ingham County Michigan, a computer groundwater database and a computerized mapping system called C-Map have proven to be valuable tools for analyzing, tracking, and recording public health concerns. This paper describes one such project: the Ingham County database was used to study an area where groundwater quality may be a public health issue. Mapping Groundwater Chemistry The Ingham County Health Department, located in Lansing, Michigan “Lansing” redirects here. For other uses, see Lansing (disambiguation). Lansing is the capital city of the U.S. state of Michigan, and the state's sixth largest city. , developed a computerized database of groundwater chemistry information beginning in 1982. The database was created to help assess the quality of groundwater, which is the primary source of drinking water for Ingham County. Up to 33 inorganic parameters, including the major cations and anions, are addressed in this water chemistry information. In this ongoing project, a total of 1,753 water supply wells have been sampled. A first report on the groundwater database was written in 1988 [1]. The database enabled the study of chemical trends and patterns within two aquifer aquifer (ăk`wĭfər): see artesian well. aquifer In hydrology, a rock layer or sequence that contains water and releases it in appreciable amounts. systems in the county. These systems included bedrock and a glacial-drift aquifer. One section of the 1988 report described a computer mapping program called C-Map, which was used to show the geographic distribution of water hardness throughout the county [2]. Most water wells in Ingham County are considered to have hard water, reflecting the concentration of calcium carbonate calcium carbonate, CaCO3, white chemical compound that is the most common nonsiliceous mineral. It occurs in two crystal forms: calcite, which is hexagonal, and aragonite, which is rhombohedral. . The C-Map program showed an area in the county with naturally soft water wells (Figure 1). Any well with a calcium carbonate concentration of 200.0 parts per million (ppm) or less was considered naturally soft [3]. The computerized map indicated that most of the soft-water wells were located in the northeast quadrant quadrant, in analytic geometry quadrant. 1 In analytic geometry, one of the four regions of the plane determined by two lines, the x-axis and the y-axis. of the county around the city of Williamston. The unique geologic condition that produced softer water in this area of the county was a topic of further review. Groundwater Quality in Three Aquifer Systems In western Ingham County, the bedrock material is predominantly sandstone sandstone, sedimentary rock formed by the cementing together of grains of sand. The usual cementing material in sandstone is calcium carbonate, iron oxides, or silica, and the hardness of sandstone varies according to the character of the cementing material; quartz , and groundwater chemistry is controlled through direct recharge re·charge tr.v. re·charged, re·charg·ing, re·charg·es To charge again, especially to reenergize a storage battery. re of water through both the glacial-drift and the sandstone materials [3]. In the Williamston area, water wells drilled into the bedrock contained more shale material. Groundwater chemistry in this area is controlled by "shale membrane filtration," not by recharge of water through glacial-drift material or sandstone [3-5]. This information suggested that the county has three aquifer systems: a glacial-drift system, a sandstone bedrock system and a shale bedrock system. A study by Slayton examined three aquifers The following is a partial list of aquifers around the world. A of aquifers is also available. North America Canada
prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. Slayton, the sodium probably does not originate from any lower-bedrock formation containing brine brine a salt solution used in the curing of meat. Standard ingredients are sodium chloride (15 to 30%) and sodium nitrate (0.15 to 1.50%) but many other ingredients may be added for special effects. brine shrimp see artemia. or salt groundwater, because the groundwater in the shale bedrock area also is low in chloride. Salt water would contain high levels of both sodium and chloride. By contrast, glacial-drift water wells in this same shale bedrock area are not "sodium rich" and, as expected, have hard-water chemistry similar to that of glacial-drift and sandstone bedrock wells elsewhere in the county. Most water wells in Ingham County have "hard" water, and water-softening devices are needed to make this water suitable for domestic use. Hard water is characterized by low levels of sodium and high levels of calcium, magnesium, and iron. A review of the water chemistry database for Ingham County showed the opposite water characteristics for bedrock wells with naturally soft water: much higher levels of sodium and lower levels of calcium, magnesium, and iron (Table 1). Like the Slayton study, the Ingham County database found that this naturally soft water does not appear to be connected to some source of brine or saltwater because it also is low in chloride [6]. Boron and Groundwater About the same time the report on Ingham County groundwater chemistry was being developed, the medical community became interested in the effects of boron in reducing osteoporosis osteoporosis (ŏs'tēō'pərō`sĭs), disorder in which the normal replenishment of old bone tissue is severely disrupted, resulting in weakened bones and increased risk of fracture; osteopenia , a bone disorder common in older women [7]. This research had shown that a boron supplement of 3 ppm reduced the urinary excretion excretion, process of eliminating from an organism waste products of metabolism and other materials that are of no use. It is an essential process in all forms of life. In one-celled organisms wastes are discharged through the surface of the cell. both of calcium and of magnesium. At the same time, several reports also indicated a health concern over ingestion ingestion /in·ges·tion/ (-chun) the taking of food, drugs, etc., into the body by mouth. in·ges·tion n. 1. The act of taking food and drink into the body by the mouth. 2. of boron and its negative effects on the male reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the female reproductive cells (the eggs, or ova) and contains an organ in which development of the fetus . The U.S. Environmental Protection Agency (U.S. EPA EPA eicosapentaenoic acid. EPA abbr. eicosapentaenoic acid EPA, n.pr See acid, eicosapentaenoic. EPA, n. ) has since issued a health advisory that recommends a limit of 0.9 ppm for long-term (usually seven years') exposure to boron in drinking water for a 10 kg child [8]. A further complication is that boron also is important in agriculture. Boron is essential for plant growth, but the amount of boron to which plants are exposed is critical. The difference between a level sufficient for proper plant growth and a toxic level can be very small, depending on the plant species [9]. Since the Ingham County groundwater quality survey analyzed for boron, wells with boron levels equal to or greater than 1.00 ppm also were mapped on the C-map program (Figure 1). It was of special interest to see that the mapped soft-water wells were located in the same general area as the wells with high levels of boron. Thus, computerized mapping, along with the groundwater quality database, revealed a potential groundwater safety concern. For the first Ingham County report on the groundwater database, boron-to-sodium values and boron-to-water-hardness values were plotted and a Spearman spear·man n. A man, especially a soldier, armed with a spear. rank correlation In statistics, rank correlation is the study of relationships between different rankings on the same set of items. It deals with measuring correspondence between two rankings, and assessing the significance of this correspondence. analysis was conducted. Results are given in Figure 2, Figure 3, and Table 2. A significant positive correlation Noun 1. positive correlation - a correlation in which large values of one variable are associated with large values of the other and small with small; the correlation coefficient is between 0 and +1 direct correlation was found between boron and sodium, and a significant negative correlation Noun 1. negative correlation - a correlation in which large values of one variable are associated with small values of the other; the correlation coefficient is between 0 and -1 indirect correlation was found between boron and water hardness. Boron and Shale Bedrock Since boron levels appear to be related to natural softness in groundwater, a statistical analysis of the boron levels in water supply wells and bedrock material was conducted to assess a possible correlation with shale bedrock material. The county groundwater chemistry database matched sampling results with corresponding well construction records. The matched information was organized into the following three groupings: glacial-drift wells, soft-water bedrock wells, and hard-water bedrock wells. A general statistical summary of water chemistry for these three groups is given in Table 1. The naturally soft water, with elevated sodium and boron values, is essentially restricted to the bedrock aquifer system. No glacial-drift wells within the county had naturally softened water chemistry, either in the western part of the county or in the eastern soft-water area. This finding further suggests that the phenomenon of boron water chemistry linked to softness is related to shale rock material rather than to glacial-drift material. To evaluate cause and to assign the water chemistry effect to shale or sandstone bedrock, a tabulation tab·u·late tr.v. tab·u·lat·ed, tab·u·lat·ing, tab·u·lates 1. To arrange in tabular form; condense and list. 2. To cut or form with a plane surface. adj. Having a plane surface. and statistical analysis was performed. This analysis compared the percentage of shale material in the soft-water wells with the percentage of shale material in the hard-water wells. The groundwater database for Ingham County contains well construction records with location, elevation, and lithology li·thol·o·gy n. 1. The gross physical character of a rock or rock formation. 2. The microscopic study, description, and classification of rock. data. Wellkey and Geology two software programs developed by the Michigan Department of Environmental Quality The Michigan Department of Environmental Quality is the agency of the state of Michigan charged with "Protecting Michigan's Environment - Ensuring Michigan's Future"[1] History , were used to manage the well records database and to gather the lithology information [10,11]. Well records were separated into two groups: bedrock wells with naturally soft water and bedrock wells with hard-water chemistry. With the Geology program, the percentage of shale lithology or material in each bedrock well was calculated. The statistical analysis was done with Statgraphics Plus software [12]. The Mann-Whitney U test Mann-Whitney U test, n.pr See test, Mann-Whitney U. for the comparison of two samples of different sizes was used to compare the percentage of shale in the soft-water and hard-water wells. Summary statistics for each well type are given in Table 3. A Spearman Rank Correlation test was also used to analyze percent shale to boron levels (Table 4). Results The analyses indicated a strong relationship between percentage shale in bedrock and groundwater softness, as well as a strong correlation between percentage shale in bedrock and the level of boron in groundwater. A significant difference was found between the median percentage shale in the soft-water bedrock wells and median percentage shale in the hard-water bedrock wells (Table 3). Soft-water wells had more shale type material (median = 75 percent shale) than hard-water wells (median = 35 percent shale). The Spearman rank correlation test also found a significant and positive correlation (.5146) between the amount of boron and the percentage shale (Table 4). Discussion, Recommendations, and Summary Results obtained in this study were consistent with Slayton's findings: In wells, shale bedrock appears to be the most significant contributing factor for natural water softness and higher levels of boron. The shale bedrock appears to function as a natural water-softening device or, perhaps, as Slayton determined, a filter that exchanges sodium for calcium and magnesium. Understanding the chemical mechanism will require further study. It is recommended that samples of bedrock from both soft and hard groundwater be collected as new water supply wells are drilled. Analysis of the bedrock mineralogy mineralogy Scientific study of minerals, including their physical properties, chemical composition, internal crystal structure, occurrence and distribution in nature, and origins or conditions of formation. or material and examination of its chemical structure and properties may help establish how shale bedrock affects water quality in the soft-water areas. Because of the public health issues discussed earlier in this paper, and because of the importance of agriculture in Ingham County, routine boron testing may be warranted for wells in the soft-groundwater area. Currently, routine tests of water wells include tests for water hardness and sodium. Boron is not usually sampled for, but if a routine test of a well indicates low hardness (less than 200 ppm as calcium carbonate) and high sodium, the boron value may be above the U.S. EPA drinking-water health advisory limit of 0.9 ppm. Thus, for wells that have naturally soft water, it is recommended that a boron test also be conducted. While high levels of boron may provide a benefit in helping to reduce osteoporosis in women, the potential negative effect on the male reproductive system is a concern. It is recommended that the county conduct a health survey of the area in which the population has been drinking the soft groundwater over an extended period of time. A lower-than-expected incidence of osteoporosis or a higher-than-expected level of male reproductive system problems would indicate that high levels of boron in the drinking water may be having health effects in humans. Plant growers plant growers, n.pl individuals who cultivate medicinally beneficial plants for use in herbal remedies. raising species sensitive to boron also will need to assess and monitor the boron levels their crops are exposed to. Because of the very narrow range between the levels of boron required for proper plant growth and levels that may be toxic, identifying a deficiency or excess is difficult. Plant growers in the soft-groundwater areas should routinely test boron levels in soil and irrigation irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e.g., rice. water. In summary, computerized mapping and a groundwater database revealed a strong correlation between shale bedrock material, natural groundwater softness, and high levels of boron in a major drinking-water source of Ingham County. Because water with more than 0.9 ppm of boron has potential risks both for human consumption and for agricultural purposes, the author recommends the following safety precautions precautions Infectious disease The constellation of activities intended to minimize exposure to an infectious agent; precautions imply that the isolation of an infected Pt is optional, but not mandatory. : * Routinely test for boron levels in wells that have naturally soft water (water hardness of less than 200 ppm as calcium carbonate). * Survey area residents for possible health effects of boron levels in drinking water, especially reduced incidence of osteoporosis, increased incidence of male reproductive problems, and increased incidence of toxic effects on agricultural crops. * In conjunction with these steps, there should be a public information program to alert the public to the potential risks of using the water. In this study, computerized mapping and a groundwater database were essential tools in improving understanding of groundwater chemistry and hydrogeology hy·dro·ge·ol·o·gy n. The branch of geology that deals with the occurrence, distribution, and effect of ground water. hy . These tools have improved the ability of Ingham County to help develop community-planning programs and propose legislation that further protects public health and drinking water resources. The Ingham County Health Department would like to hear from readers who can provide other examples of ways in which computer mapping and databases have helped ensure the safety of drinking-water resources. Corresponding Author: Garry Rowe, Ingham County Health Department, Bureau of Environmental Health. REFERENCES (1.) "Report on the Aquifers of Ingham County" (1988), Lansing, Mich.: Ingham County Health Department. (2.) Center for Remote Sensing Deriving digital models of an area on the earth. Using special cameras from airplanes or satellites, either the sun's reflections or the earth's temperature is turned into digital maps of the area. (1989), "C-Map Computer Mapping Display and Analysis," In User Manual Version 1.03, East Lansing East Lansing, city (1990 pop. 50,677), Ingham co., S central Mich., a suburb of Lansing, on the Red Cedar River; inc. 1907. The city was first known as College Park, but was renamed when it was incorporated. , Mich.: Michigan State University Michigan State University, at East Lansing; land-grant and state supported; coeducational; chartered 1855. It opened in 1857 as Michigan Agricultural College, the first state agricultural college. (3.) Vanlier, K.E., J.D. Brunett, and W.W. Wood (1969), Water Supply Development and Management Alternatives for Clinton, Eaton and Ingham Counties, Geological Survey The term geological survey can be used to describe both the conduct of a survey for geological purposes and an institution holding geological information. A geological survey Water-Supply Paper, Stock No. 2401-02442, Prepared in cooperation with the Tri-County Regional Planning regional planning: see city planning. Commission and Michigan Department of Natural Resources The Michigan Department of Natural Resources is the agency of the state of Michigan charged with maintaining natural resources such as state parks, state forests, and recreation areas. , Washington, D.C.: U.S. Government Printing Office. (4.) Kharaka, Y.K., and F.A.F. Berry (1973), "Simultaneous Flow of Water and Solutes Through Geological Membranes--I. Experimental Investigation," Geochimica et Cosmochimica Acta, 37(12):2577-2603. (5.) Wood, W.W. (1976), "A Hypothesis of Ion Filtration in a Potable-Water Aquifer System," Groundwater, 14(4):233-244. (6.) Slayton, D.F (1982), "Field Evidence for Shale Membrane Filtration of Groundwater, South-Central Michigan," M.S. thesis, East Lansing, Mich.: Michigan State University. (7.) Nielsen, F.H., C.D. Hunt, J.R. Hunt, and L.M. Mullen (1987), "Effect of Dietary Boron on Mineral, Estrogen, and Testosterone testosterone (tĕstŏs`tərōn), principal androgen, or male sex hormone. One of the group of compounds known as anabolic steroids, testosterone is secreted by the testes (see testis) but is also synthesized in small quantities in the Metabolism in Postmenopausal post·men·o·paus·al adj. Of or occurring in the time following menopause. postmenopausal Change of life Gynecology adjective Referring to the time in ♀ when menstrual periods stop for ≥ 1 yr Women," Federation of American Societies for Experimental Biology The Federation of American Societies for Experimental Biology, or FASEB, is a non-profit federation of 21 societies for biomedical research in the United States. Its mission statement is "to advance biological science through collaborative advocacy for research policies that Journal, 1:394-397. (8.) Office of Water (1996), "Boron Drinking Water Health Advisory," Drinking Water Regulations and Health Advisories, EPA 822-R-96-001, Washington, D.C.: U.S. Environmental Protection Agency (9.) Sprague, R.W (1972), The Ecological Significance of Boron, Los Angeles Los Angeles (lôs ăn`jələs, lŏs, ăn`jəlēz'), city (1990 pop. 3,485,398), seat of Los Angeles co., S Calif.; inc. 1850. , Calif.: U.S. Borax borax or sodium tetraborate decahydrate (sō`dēəm tĕ'trəbôr`āt dĕk'əhī`drāt), chemical compound, Na2B4O7·10H2O; sp. gr. 1. Research Corporation and Anderson, Ritchie and Simon--The Ward Ritchie Press. (10.) Land and Water Management Division, Geological Survey Division (1989), Wellkey Software, Version 2.1, Lansing, Mich.: Michigan Department of Natural Resources. (11.) Land and Water Management Division, Geological Survey Division (1994), Geology--Statistical Analysis of Wellkey Data Software, Version 2.1, Lansing, Mich.: Michigan Department of Natural Resources. (12.) Statgraphics Plus, Version 7 for DOS (1993), Rockville, Md.: Manugistics, Inc.
Water Chemistry of Glacial-Drift Wells, Soft-Water
Bedrock Wells, and Hard-Water Bedrock Wells [*]
Well Type n Alkalinity Boron [**] Calcium
Glacial-drift wells 255 (98) [**] 275.0 0.03 96.2
Soft-water bedrock wells 207 283.0 1.41 36.8
Hard-water bedrock wells 1,047 278.0 0.05 83.6
Well Type Chloride Iron Magnesium Potassium Sodium
Glacial-drift wells 26.0 0.9 33.2 1.6 11.0
Soft-water bedrock wells [less than]2.0 0.2 9.6 3.8 74.0
Hard-water bedrock wells [less than]2.0 0.8 27.0 1.8 7.0
Well Type Sulfate
Glacial-drift wells 58.0
Soft-water bedrock wells 9.0
Hard-water bedrock wells 36.0
(*.)Median values, given as parts per million.
(**.)For boron testing, the glacial-drift sample size was 98.
Spearman Rank Correlations of Boron to Sodium and Boron to Hardness
Boron Sodium Hardness
Correlation 1.0000 .5446 -.4413
Sample size 659 659 659
Differences in Shale Bedrock Percentages for Hard-Water
and Soft-Water Wells
Hard Water (% Shale) Soft Water (% Shale)
Sample Size 316 78
Median 0.35 0.71
Mode 0.22 0.86
Range 0.01-0.94 0.11-0.95
Test: unpaired Mann-Whitney U test (394 total observations)
Average rank of hard-water percentage shale = 174.055 based on 316 values.
Average rank of soft-water percentage shale = 292.481 based on 78 values.
Large-sample test statistic Z = 8.22511
Two-tailed probability of equaling or exceeding Z = [2.22045E.sup.-16]
Spearman Rank Correlations
Test for Boron to Percentage
Shale in Sampled Wells
Boron % Shale
Correlation 1.0000 .5146
Sample size 393 393
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