There is a significant difference among the mean nitrite concentrations of the clusters .
7.0 Interpretation of the NO 3 - concentration
All the values are below the maximum permissible level.
7.1 Results Obtained from the Statistical Analysis
One-way ANOVA: Nitrate versus Clusters
Source DF SS MS F P
Clusters 3 7.417 2.472 3.13 0.030
Clusters = A subtracted from:
Clusters Lower Center Upper ---------+---------+---------+---------+
B -0.6635 -0.0117 0.6401 (--------*--------)
C -1.0504 -0.3523 0.3458 (---------*---------)
D -1.3165 -0.6584 -0.0003 (---------*--------)
-0.70 0.00 0.70
There is a significant difference among the mean nitrate concentrations of the clusters .
8.0 Interpretation of Total Iron
Iron is present in laterite soil.
Deposition of soft soil.
9.0 Interpretation of the Dissolved Oxygen
In fresh water DO level at 25°C is 8.4 mg dm -3 .
Groundwater contamination by organic waste.
10. Interpretation of the Chemical Oxygen Demand
Organic and oxidizable inorganic substances.
11. Interpretation of the Manganese Concentration
50% of the samples are above the maximum desirable level.
12. Interpretation of the Zinc Concentration
High concentrations in cluster A.
13. Interpretation of the BOD Values
About 40% of the samples.
Presence of organic materials .
14. Interpretation of the Results of Coliform and E.coli Test
The maximum permissible level is10 coliform organisms per 100 cm 3 .
Out of 6 samples, 4 samples showed high MPN values.
2 samples in clusters C and D were detected as contaminated with E.coli bacteria.
Considering the pH value, water of 95.8% of wells is not suitable for drinking.
With respect to conductivity and turbidity , well water is safe to drink.
Total solids were moderately low.
The NO 2 - concentrations were found to be rather high.
Moderately high concentrations of NO 3 - were found around the university.
The iron concentration and total hardness were found to be low.
When considering the DO, COD, and BOD values, the groundwater is polluted.
Zn and Mn concentrations were significant in the area around the university.
Pb and Cr were found to be absent.
Groundwater contamination by Coliform and E.coli bacteria was significant around the garbage dumping site.
Some wells located in the direction of natural water flow from the dumping site have been affected adversely.
Human activities have been adversely affected on the groundwater quality.
The deterioration of the quality of groundwater takes time because undesirable products take time to penetrate through the soil layers.
In general, groundwater in the area is not suitable to be considered as potable water.
Suggestions for further work
Carrying out investigations during both dry and wet seasons.
Identification of the variation of the contamination level with the distance from any significant location by GPS measurements.
The wells that were highly polluted can be studied separately.
Sanitary landfill sites should be designed.
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