Global Journal of Science Frontier Research, H: Environment & Earth Science, Volume 23 Issue 2

Magnesium hardness was determined simply by subtracting the calcium hardness from the total hardness. The determinations were made after refrige- rated samples had been allowed to attain room temper- ature. The CO150 conductivity/TDS portable meter was used. The sample was poured into a 100mL beaker. The conductivity meter was calibrated by dipping the probe in distilled water. It was then transferred into the sample and the value recorded. The procedure was repeated for all the other samples. a) Total dissolved solids (TDS) determination A 50mL well-mixed sample was measured into beaker. The CO150 conductivity/TDS portable meter probe was immersed in the sample and its total dis- solved solids recorded [28]. The stored program number for colour was en- tered into HACH DR/2000 spectrophotometer with the wavelength set to display ‘PtCo Colour’ units. A sample cell was filled with 10 mL of filtered deionized water (the blank). A second sample cell was filled with 10 mL of filtered sample (prepared sample). The blank was placed into the cell holder to zero the spectrophotome- ter followed by the prepared sample. The result in Plati- num-Cobalt Units was displayed and value recorded. The procedure was repeated for the other collected samples. The stored program number for turbidity was entered into HACH DR/2000 spectrophotometer with the wavelength set to display ‘NTU Turbidity Units’. Two sample cells were obtained. One was filled with 10mL of filtered deionized water (the blank) and the other was filled with 10mL of the prepared sample. The blank was placed into the cell holder to zero the spectrophotome- ter followed by the prepared sample. The results in Ne- phelometric Turbidity Units was displayed and value recorded. The procedure was repeated for the other collected samples and the mean value taken. An aliquot of 10mL of sample was measured in- to a conical flask. The pH was then adjusted to a range of 7-10 with H 2 SO 4 for high pH samples and with NaOH for low pH samples. Two drops of K 2 CrO 4 indicator was added. The colour change obtained was yellow to red- dish brown. The procedure was repeated two more times and the average titre value calculated. This proce- dure was repeated for all the samples collected. Chloride (mg C1 - /L) = X×N×1000×35.5/1mL of sam- ple X=end point volume N=Normality of AgNO 3 b) Alkalinity Determination (Methyl Orange Alkalinity) The total alkalinity as expressed in terms of cal- cium carbonate present was determined by titration us- ing standard 0.02N H 2 SO 4 with methyl orange as indica- tor to the first permanent pink colour for pH<8.3. For pH>8.3, phenolphthalein is used. Since all the pH val- ues were less than 8.3, only methyl orange was used hence methyl orange alkalinity was determined. There was no phenolphthalein alkalinity for any of the samples. 10mL of the sample was measured into a conical flask and two drops of 5% methyl orange indicator was add- ed and swirled to mix. It was titrated against standard 0.02N H 2 SO 4 with continuous swirling. A colour change of yellow to orange was obtained when the endpoint was reached. The titre value was then recorded. The procedure was repeated for each sample and the aver- age titre value was calculated. The procedure was re- peated for all the collected samples. The alkalinity con- centration was calculated as; Alkalinity mg (CaCO 3 )/L = A×N×50,000/1mL sample [28]. Where A=mL of acid used and N= Normality of standard acid used The stored program number for iron, FerroVer method was entered into spectrophotometer with the wavelength set appropriately. A clean cell sample was filled with 25mL of sample and the content of one Fer- roVer Iron reagent was emptied into the sample cell (the prepared sample). An orange colour was an indication of the presence of iron. The shift timer button was pressed and allowed for about five minutes to allow for a reaction to take place. 25mL of blank solution in cell was place in the cell holder and the light shield was closed to zero the spectrophotometer. The blank was then removed and the prepared sample was put into the cell holder and the result was displayed in mg/L Fe FV. The procedure was repeated for the rest of the collected samples. c) Bacteriological Analysis Total coliforms and faecal coliforms were enu- merated by multiple tube fermentation tests as de- scribed by [28]. In the multiple-tube method, a series of 5 tubes with Durham tubes containing a suitable selec- tive broth culture medium (lactose-containing broth, such as MacConkey broth) were inoculated with test portions of water sample from each of the boreholes. After an incubation time of 24-48 hours at a temperature of 37 ℃ , each tube showing gas formation in the Durham tubes and a colour change was regarded as “presump- tive positive” since the gas indicates the possible pres- ence of coliforms. However, gas may also be produced by other organisms, and so a subsequent confirmatory test is essential. The two tests are known respectively as the presumptive test and the confirmatory test [28]. For the confirmatory test, a more selective cul- ture medium (brilliant green bile broth) was inoculated with material taken from the positive tubes. After an ap- propriate incubation time of 24-48 hours and tempera- ture of 44.5 ℃ , the tubes were examined for gas formation as before. The most probable number (MPN) of bacteria present can then be estimated from the number of tubes inoculated and the number of positive tubes obtained in © 2023 Global Journals 1 Year 2023 80 Global Journal of Science Frontier Research Volume XXIII Issue ersion I VII ( H ) Assessment of Water Quality of the Nalerigu Dam in the East Mamprusi Municipality of the North East Region of Ghana