UNDERGROUND WATER QUALITY OF ROCK MINING IN ISHIAGU, EBONYI STATE, NIGERIA

P h y sic oc h e m ic al and bac te riolog ic al analy sis of unde rg round w ate r of C rush R oc k m ining pit in Ish iag u, Ebony i S tate N ig e ria w e re c arrie d out to de te rm ine d th e pollution le ve l and th e potability of th e g roundw ate r due to m ining and h um an ac tivitie s. T h e re sults w e re c om pare d w ith standards for w ate r pollution and World H e alth O rg aniz ation for drink ing w ate r. T h e re sults sh ow e d th at total dissolve d solids (T D S ), total alk alinity , c alc ium and sodium , w h ic h h ad c onc e ntration rang e s of 126-9 86ppm , 200.18-615 .5 5 ppm , 7.830.10ppm and 64 -88ppm re spe c tive ly , w e re above standards. H ow e ve r, th e m e an conc e ntration of dissolve d ox y g e n (D O ) (1.2-3.20ppm ) w as be low th e standard. O th e r param e te rs m e asure d w e re found to be w ith in th e pe rm issible ac c e ptable standard. f?g hJi)j k l^k m n"g o p2qGrDk lsk(tDn?u v h7r4w i(lso x+n u w!y y i(g o3z2g u0qah r4w4u q w4n o"{ v n |(q }?y0k(u k(u u i(g o ~ y n? kDt6n?u v h0r4w iDlso ew u r6k(u"k(u"u iDg oDp6w v rDkDt2n u"v h r and Uu3q r6k lsk(t2n?u v h r&g pe c ie s w e re ide ntifie d as th e m ajor bac te ria isolate d from th e unde rg round w ate r. T h e study re ve ale d th at th e unde rg round w ate r from C rush R oc k m ining pit in Ish iag u Ebony i S tate , N ig e ria re q uire som e c h e m ic al and ph y sic al tre atm e nt as it is unsafe for h um an c onsum ption. 6?D?(  U nde rg round w ate r; P otability ; P ollution; Bac te ria.


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Estud.Biol., v. 28, n.63, p. 61-71, abr./jun.2006 Underground water is a body of water occurring in the subsurface especially in the zone of saturation where all the pores and cracks are filled with water.During the percolation of groundwater, it takes along dissolved organic and inorganic materials.Microorganisms are frequently trapped on the surface water and as the water percolates some of the microorganisms will find their ways into the groundwater.
G lobal industrialization, Africa inclusive, has resulted in increased demand for this natural resources, water and this is more severe in the third world countries like Nigeria.The discharge of untreated or fairly treated wastes into ecosystems brings about structural, physical and chemical changes which often affect the biota (1) The physicochemical attributes of any water body are prime factors which influence its overall productivity, reproduction, and growth performance (2).Of notable importance are pH, transparency, temperature, dissolved oxygen, suspended solids, biochemical oxygen demand and dissolved ions, of which, play critical role in determining the suitability of .thewater for aquatic life as well as for other human uses (3).Any alteration of these water parameters, either through anthropogenic activities or natural disaster, often results in concomitant alteration of the aquatic life.WHO (4) described water not only as a giver of life but also as a source of many human diseases.The status of biological communities, particularly bacteriological quality, in water is of direct interest to microbiologists, hydrobiologists, public health officers, town planners, statisticians, engineers etc., as it serves as a measure of the extent of pollution in the system.
Monitoring the pollution level of water bodies in the developed world has been a continuous process (5,6,7), but the pollution level of Nigeria's water has not been adequately monitored.The scourge of water and soil pollution on our people cannot be over emphasized and had made studies directed towards such investigations to be of utmost importance in alleviating the accompanying undesirable impact on the populace.Furthermore, the awareness such studies would create would be invaluable to our national government and other international organization in the realization of a healthy populace.This is of utmost importance and interest, especially now that there is global call on governments to give priority attention to environmental protection efforts in their countries (4, 6 8).
Following the various industrial (especially rock mining), agricultural and commercial activities taking place in Ebonyi State, South-East Nigeria, this work is aimed at evaluating the effects of crush rock in Ebonyi State Nigeria.

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was lowered to about 15cm depth to collect representative water sample.The samples were transported to the laboratory within 2-4 hours and stored at 40 o C prior to analysis.
The temperature of the water was determined with a digital mercury thermometer and the turbidity of the water sample was determined with turbidimeter (9).Conductivity was determined by the method in Philips manual of laboratory conductivity meter (1O).Total dissolved solid (TDS) was indirectly determined using the equation: TDS = Conductivity / 2 (11).The total suspended solids (TSS) were determined by cal1ing up the program number (20) for total suspended solids on the Shimadzu UV -160A-recording spectrophotometer at 400 nm.Following standardization with distilled water as blank, the samples were then introduced and the values read off as displayed on the screen (11).The pH was determined using Corning digital 112-pH meter.
Sulphate, chloride, sodium, potassium, alkalinity, silica, and dissolved oxygen content were determined by the methods outlined in standard methods for examination of Water and Waste Water (12).Calcium ion (hardness) was estimated by application of the method report in Hachwater Analysis Hand Book (11,13).
The trace / heavy metals (Pb, Z n, Fe, Cd and Cu) content were assayed with Atomic Absorption Spectrophotometer, Unican 969 in an air-acetylene flame.
Bacteriological investigation was carried out by pour plate method on a nutrient agar which was prepared according to the manufacturer's instruction, and was sterilized in the autoclave at 121 o for 15 min.one milliliter of each water sample was transferred with sterile pipette into sterile petri dishes.The agar was poured into each of the petri dishes.The petri-dishes were rocked gently to mix the agar and the water sample.The plate was later incubated at 37 o C for 24-48 hours for bacteria.At the end of the incubation, the colonies that developed in plates were counted with colony counter.The isolates were further characterized and identified by carrying out Grem staining, catalase, citrate, oxidase and some other biochemical tests.
Table V showed that bacteria species made up of Gram positive and Gram negative organisms were isolated from the underground water.
They included Pseudomonas, Chromobacterium, Bacillus, ae ç tè qé ê Të 4ì Qè qé ì 'í , and î ï í §ð é §ñ Xò Qó #è ó #è è ô ç species.Others were õ ò Uí §ö tó c÷ Aí è ï ê hë !ì ©ô §ø , ù ¥ì 'è Pë %ó è Pó è Pè #ô ç , ú 8ì ï ë %ó ÷ Aí è ï ê hë and û è hé §ë ©ó qø ó q÷ cí Aè ï ê 4ë species.It is difficult to find a river or other body of water whose natural regime has not been modified in one way or another by man's activity.At the same time, man really depends on water for domestic consumption, industrial, recreational and agricultural purpose and the quality of water for each purpose differs tremendously.The result of our study revealed that the mean pH concentration for dry (7.62) and rainy (7.8) seasons were within the range of 7-8.5 as set by WHO ( 14) for drinking water.pH which is bellow 7 can impart a sharp acid taste to water and can easily corrode the pipe borne plumbing (11).The temperature range of 26.1-27.1 o C falls within the normal international standard for discharge into streams.The mean value of temperature was found to be higher in dry season (27.52 (15).It is important to note that temperature exerts a marked effect upon the pollutional characteristics of a stream or water body since the amount of oxygen that a water body can carry is inversely proportional to the temperature of the water body.The temperature values for the study did not vary much in both seasons.A water body whose temperature rises above 33 o C is generally considered unsuitable for public water supplies (16,17,18).Turbidity is one of the water characteristics, which although not harmful to the health of people using it but may affect its acceptability as a domestic supply.The international standard sets the maximum permissible level for turbidity at 25 units (19).The results indicated clearly that the rainy season mean turbidity value.(61.97 NTU) was higher than the dry season value (9.32 NTU).That is the rainy season value was above the international standard while the dry season value was below the WHO standard.The implication of the higher values of turbidity is that more energy and chemicals will be needed in rainy season than in the dry season at the treatment plant (16).
The conductivity values were highest in the months of October, 2002 (1871 ms/cm) and December 2003 (1453 ms/cm).The least values of 250 ms/cm, 253 ms/cm, and 359 ms/cm were recorded in the months of August 2002, August 2003 and June 2003 respectively (Table 1).The lower mean values of conductivity observed in the rainy season (413.67ms/cm) when compared with dry season value (1229.5 ms/cm), had been attributed to the dilution effect of rains.These values are within the acceptable standard limits of 300 ms/cm (20,16).Total suspended solids (TSS), total dissolved solids (TDS) and dissolved oxygen (DO) were higher in dry season than in rainy season.This is due to the dilution effect of rainy and reduced mining activities during the rainy season.The TSS was relatively good since its concentrations were within the minimum acceptable standard for domestic use and many industrial purposes.The value of TDS was however above the permissible international standard of 500 ppm.This is objectionable since water higher in dissolved solids should be viewed as potentially corrosive to well screens and other parts of well structure (21).The low range of DO (1.2-3.20 ppm) recorded during the study is an indication that the underground water of Crush Rock mining is not suitable for aquatic life.This is because under favorable environmental conditions, a minimum constant value of 5 ppm (DO), is satisfactory for sustenance of aquatic biota including fishes (15,22).The total alkalinity reported in terms of their equivalent carbonate had range values of 200.18 -615.55 ppm, with higher mean value of 349.83 ppm in dry season and lower value of 234.25 in rainy season.The total alkalinity concentrations exceeded the WHO standard throughout the sampling period.The concentrations of some parameters such as potassium, sulphate and chloride were found to be within the minimum acceptable and maximum allowable WHO standards for drinking and domestic purposes.Nduji reported that chloride, sulphate and nitrate ion content of Nigerian surface and underground waters are negligible when compared with WHO standard (23).Other researchers made similar findings (11,15,16,24,25).
Concentrations of calcium and sodium were found to be well above the maximum acceptable WHO limit.The high values of calcium and sodium recorded may be attributed to the partial solubility of the calcium carbonate (CaC0 3 ) and other minerals that are component of the quarry stone (11,26).This observation agrees with earlier findings of this work on increased level of alkalinity since carbonate had been known and Estud.Biol., v. 28, n.63, p. 61-71, abr./jun.2006 § C 7 £ 4 4 © 8 © 4 © E reported to increase alkalinity (27).There is no reliable standard for silica content in drinking water, however, the silica values of the samples ranged from 2.120 -3.590ppm.Higher values of silica had been reported and were attributed to the silty nature of the soil or blasting activities of the rock or probably due to other redox activities (11,28).Resu1ts obtained showed that the rate of accumulation of these heavy meters in the underground water did not vary as such among the samples examined.In all the samples examined, some metals were not detectable.Overall, seasonal variation of these metals shows that rainy season has relatively mean higher values for iron and cadmium than in the dry season.
Copper on the other hand had higher mean value in the dry season than rainy season.Lead and Zinc did not display any seasonality thoughout the study.All the values obtained in the present study are however below WHO standard limit (20), FEPA (29) and DPR (30).Although, these trace metals differ widely in their chemical properties, their relative concentrations and discharges and hence, their bioavailability are very important to terrestrial, aquatic and marine organisms in terms of toxicity (31).The emission of these heavy metals often result in extensive and persistent contamination of water and vegetation.The overall effects of the resultant emissions, on the living organisms including animals and humans are many and often life threatening.For example lead is known to produce developmental neurotoxicity and it has been shown that infants, children and pregnant women may be differentially sensitive to environmental lead exposure.Lead can cause abdominal panis, vomiting, drowsiness, convulsion, malfunction of the kidney, reproductive system, liver, brain and the central nervous system structural abnormalities, altered growth and functional deficits, sexual maturity and consequently death (11,15,32,33,34,35).Zinc has low toxicity to man, but relatively high toxicity to fish (36).Thus, contamination of aquatic environments with larger quantities of zinc would cause massive death to fish (37).Although sterile water devoid of microorganisms rarely exist except in the laboratory (38), studies have shown that strategies abound for the treatment of water meant for human consumption to permissible level of microbial flora especially coliform (14,19,20).Thus, the present results suggest that the underground water require further microbiological treatment if the water should be used as drinking water.The results corroborate the levels of microbial flora obtained in other works (11,15,26,39).The presence of & 9 ¥ ¡ 7¢ £ § ¥¢ ££ ¤ ¥ %¦ ¢ , § ¡ © ¥ §ª «¥ ¬ £ ® ¯., °' ¥ §ª «¥ ± £ B² 7 ©¢ ©ª ³ ¯. in the water samples is indicative of fecal or related pollution due to either humans or animal (reptiles, birds and rodents) activities.B² C£ 6& 6µ ¦ !¥ B¥ E B % § may have originated from human activities which is indicative of lack of personal hygiene of the miners.There was evidence of indiscriminate defecation and absence of drainage systems in the study area.The surface run off of waters into the mining probably seems to be the major source of the bacterial contamination.Pseudomonas and Bacillus were isolated from the water sample throughout the study and their consistent isolation could be associated with the physiological nature of the organisms usually in water where they can survive with very minimal nutrients as reported by Caincross et al. (40) and Ogbulie and Akujiobi (41).The trend in the isolation of these bacterial species reveals the characteristic microbial contamination of the underground water and the high incidence of some of them in the samples indicate the ability of these organisms to thrive in different environments.¶ • ¸¹ Eº E» ½¼ ¾ ©• F rom the chemical and bacteriological analysis of the underground water, it is evident that the underground water investigated is polluted as compared with standards.Therefore, it is not portable.The pollution level of the underground water is due to the mining activities, human and animals (reptiles, birds, and rodents) activities, water run off and improper refuse and sewage disposal around the mining area.
It is suggested that the state, local government, ministries or agencies responsible for the environmental health, minerals, labour etc. should make and enforce laws on mining, sewage and refuse disposal.Adequate drainage system should be provided to protect the pit and minimize the pollution of the water.It is strongly recommended that these waters should be treated before being used for drinking and other domestic purposes.