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INTRODUCTION
1.1 GENERAL STATEMENT
Water is one of the most essential needs of human beings and is the most abundant natural
resources on the surface of the earth (Oyinloye and Jegede, 2004). It is one of the most
indispensable resources and it is the elixir of life, it constitutes about 65 -75% of body weight of
almost all living organism (Annan, 2005/Idiata, 2006/Fox, 1996). Sometimes, like 40% of
human race do not have adequate access to safe water. When water in its original sources is
contaminated by domestic, industrial or agricultural waste and is sufficient to render the water
unacceptable for its best usage, it is said to be polluted. The substances causing these
unfavorable alterations are called “pollutants” (Ekpete, 2002).
Water can be obtained mainly from two sources namely surface water and groundwater.
Surface water is any water that travels or is stored on top of the ground. This would be the water
that is in rivers, lakes, streams, reservoir and even the oceans .Rain water is probably the purest
form of natural water, since it is obtained as a result of evaporation from the surface water.
Rivers are the principal sources of water supply for many cities and towns. But the quality of
surface water obtained from rivers is not reliable because it contains suspended matter and
number of other impurities.
Groundwater is an important source of water for agricultural and domestic use especially in
developing countries like Nigeria, due to long retention time and natural filtration capacity of
aquifers, groundwater is the largest reservoir of drinkable water and due to the natural filtration,
and it is less contaminated as compared to surface water (Aiyesanmi et al., 2004)
However, leachate from municipal, solid waste and landfills are potential sources of
contamination of both surface water and groundwater (Odukoya et al., 2002).Pollution of
groundwater has gradually been on the increase especially in our cities with lots of industrial
activities, population growth, poor sanitation, land use for commercial agriculture and other
factors responsible for environmental degradation (Egila and Terhemen, 2004).The effects of
pollution as a result of variations in physico-chemical and biological parameters render surface
water unsafe for human and recreational use. Considering the fact that it poses threat to human
life, it’s therefore against the principle of sustainable development.
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Water borne diseases and water related health problems are mostly due to inadequate and
incompetent management of water resources. Safe water for all can only be assured when access,
sustainability and quality are guaranteed. There should be an effort to sustain it and there has to
be a fair and equal distribution of water to all segments of the society (Ochuko, 2013).
Thus, significant variations in physico-chemical parameters affect the quality of a water
resource. Hence, it is necessary to obtain information on the variations of seasonal physico-
chemical and biological characteristics of water in order to decide on the type of water treatment
process to be adopted (Efe et al., 2005). But, clean unpolluted water is necessary for the
maintenance of human health as well as quality of the environment (UNEP, 1996). Water that is
safe for drinking, pleasant in taste, and suitable for domestic purposes is designated as potable
water and must not contain any chemical or biological impurity (Horsfall and Spiff, 1998).
Water quality data is essential for the implementation of responsible water quality
regulations for characterizing and remediating contamination and for the protection of the health
of humans and the ecosystem. The consequences of industrialization and urbanization lead to
spoiling of water. This is observed that ground water get polluted due to increased human
population, agricultural runoff, domestic sewage, industrial effluents, addition of various kinds
of pollutants and human activities. Due to use of contaminated drinking water, number of cases
of water borne diseases has been seen which causes health hazards. It is up to the people to
provide security to protect and maintain quality of water. The concentration of contaminants in
the groundwater also depends on the level and type of elements naturally or by human activities
distribute through the geological stratification of the area. The presence of such contaminants in
the groundwater, above the recommended standard set by water quality regulating bodies like
EPA, FEPA and WHO may result in serious health hazards.(USEPA, 2002).
This perceived consequence of consumption of unregulated waters (used as potable
water) has triggered various studies on water aquifer and aquatic ecosystem. (Akpa and Offen,
1993; Udom et al., 1999; Ekpete, 2002; Oguzie et al., 2002; Aiyesanmi et al., 2004 ; Egila and
Terhemen, 2004; Abam et al., 2007; Nwala et al., 2007; Bolaji and Tse, 2009). It is therefore
necessary that the quality of drinking water should be checked at regular time interval as well as
to find out various sources which increased ground water pollution. Thus in this present study an
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attempt has been made to assess the physicochemical characteristics of surface water and
groundwater of various parts of Patani, Delta State.
TABLE 1.0: WORLD DISTRIBUTION OF WATER (%) (PLUMMER AND McGEARY,
1993)WORLD DISTRIBUTION OF WATER %
Ocean 97.2
Glaciers and other ice 2.15
Groundwater 0.61
Lakes-fresh water 0.009
Saline 0.008
Soil moisture 0.005
Atmosphere 0.001
Rivers 0.0001
1.2 LOCATION AND ACCESSIBILTY
The study area is located in the southern part of Delta state and it is the headquarter of
Patani Local Government Area, Delta state which lies along the famous River Forcados that has
a boundary with Sagbama, the two parts are accessible via a bridge in between and is bounded
on the North by Ughelli North and Isoko South and North-west by Ughelli South, also on the
west by Bomadi and on the South and East to River Forcados. It is readily accessible by a
network of roads (major and minor roads).
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Figure 1.1: Geological map of Delta State
Source: NGSA, 2004
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Figure 1.2: Aerial map of Patani
Source: Google Earth view (2006)
1.3 OBJECTIVES OF STUDY
The study was aimed at investigating;
1. The physicochemical characteristics of concentrated ions present in wells, boreholes and
surface water in relation to their hazardous effects on man.
2. Some physicochemical parameters of the water of some boreholes, hand-dug wells and river
in the study area.
3. Generate data for relevant authorities and as thus could serve as an epidemiological tool.
4. Information that may also be used to reduce or eliminate the sources of pollution in the area
of interest as well as provide possible water management measures that would enhance good
water quality of surface water and groundwater sources.
1.4 SIGNIFICANCE OF STUDY
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This study is designed to supplement the work of local and federal agencies, monitoring
water quality in this region. Data generated from this study will contribute to the community
by providing precise information concerning the water quality that is currently available.
Data generated study may be shared through presentation and publication promote an
increase in understanding and potential remediation of regional hand-dug open wells,
boreholes and rivers (surface water).
1.5 RELIEF AND DRAINAGE
The center of the study area lies at latitude 5.2287989 and longitude of 6.1911526 with an
average ground elevation of 46fts.The area possess a low relief and poor drainage system. These
could be said to be as a result of the flood that occurred in the year 2012, precisely between 15th
of September to 1st of October, it overwhelmed the areas drainage system and resulted in a
widespread flooding. The flood affected over 30,000 household.
1.6 CLIMATE AND VEGETATION
Patani is located in the southern part of Delta state, Nigeria. The area has a tropical climate
marked by two distinctive seasons, the dry and rainy season. The dry season occurs between
November and April, while the rainy season begins in April and last till October. Occasional
rainfall may be experienced during the dry season.
It is characterized by heavy rainfall with average mean of 2,550-2,755mm per annum. The
near minimum annual temperature ranged from 23-31oC with a high relative humidity of about
78.82%. The study area is a low land, coastal area that falls within the freshwater swampy region
of the state.
1.7 SETTLEMENT AND LAND USE
In the study area, due to the immersed availability of water, majority of the people in the
area engage themselves in fishing and farming. Other forms of human activities are small-scaled
business. The area possesses a linear settlement pattern that is the settlements are found along
the roadside. Other settlements present in the study area are nucleated and scattered settlement.
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1.8 LIMITATION OF STUDY
One of the outstanding limitations of this work was inadequate accessibility to certain
locations. No new monitoring borehole was drilled rather just two existing active boreholes in
the area were sampled. The physicochemical analysis of water samples is a little expensive;
hence limited numbers of sampling points were used for the study. Some of the borehole owners,
I met never accepted, instead rejected sampling their borehole or demanded for payment before
sampling could be carried out.
1.9 REVIEW OF RELATED LITERATURES
Ozoemenam, (2012) carried out water quality assessment in shallow and deep boreholes in
Ekpan community, Effurun, Delta state. Twelve borehole water samples (6 each from shallow
and deep aquifers) selected randomly were analyzed for both physicochemical and microbial
constituent of water from Ekpan showing the pH, temperature, Biological oxygen demand
(BOD),Salinity, total hardness,NO3- and SO4
2+, the trace metals; Pb, Cd and Cr and total coliform
counts. From his study the concentration values of Pb, Cd, Mn and Cr, as well as BOD and total
coliforms fell within the Federal Ministry of Environment (FME, 2001) and World Health
Organization (WHO, 2004) recommended permissible limits for drinking water, water from
shallow boreholes in the area is not safe for human consumption due to pollution by chemical
and microbial parameters and the deep boreholes are safer to an extent but all contain some
element of metal ions.
Also, Egbai et al. (2013) carried out quality assessment to ascertain the water quality and
suitability of groundwater in Okwagbe Community in Ughelli South Local Government area of
Delta State, Nigeria. Water samples were collected from fifteen (15) locations evenly within
Okwuagbe community and analyzed for physico-chemical parameters which include pH
temperature conductivity, total dissolved solids (TDS), bicarbonates ions (HCO3-), Carbonate
ions (CO32-), total hardness, chloride ions (Cl-), sulphate ions (SO42-), Iron ions (Fe2+), Calcium
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ions (Ca2+), magnesium ions (Mg2+), potassium ions (K+) and sodium ions (Na+).The contrast of
the result obtained with the World Health Organization (WHO) standard revealed that the water
sample in the study area contains higher concentrations of iron than the WHO recommended
limit of 0.30mg/L especially in some locations. The analysis of water samples indicated Calcium
ions (Ca2+), Magnesium ions (Mg2+) and Iron ions (Fe2+) are the dominant cations while
Chloride ions (Cl-) and Bicarbonate ions (HCO3-) are the dominant among of the fifteen samples.
The quality and suitability of boreholes and wells in the locality are not good enough. The water
is not suitable for domestic purposes such as drinking due to high concentration of the turbidity
hardness, and iron ions in the water. Treatment to reduce these parameters should be carried out
to enhance the quality and suitability of the groundwater.
Ushurhe, (2013) carried out a comparative assessment of the seasonal variation in the
quality of water from Rivers Ase, Warri and Ethiope which was examined based on the collected
and analysed water samples from the rivers between January 2011 to December 2011. Several
physico-chemical and biological parameters were analysed. Water quality parameters such as
pH, temperature, salinity, TDS, TSS, DO, BOD, NH3N, NO3N, SO4, Coliform, Na, K, Mg, Pb,
Zn, Fe, among other parameters were analysed using Atomic Absorption Spectrophotometer,
Digital Meters, Standard Plate Count, in addition to titration methods. The results obtained were
compared with WHO, (2010) threshold. The results showed that parameters such as TSS,
turbidity, BOD, ammonia, hydrocarbon, phosphate, coliform, magnesium and iron were high in
concentration relative to WHO (2010) threshold in Rivers Ase, Warri and Ethiope; others were
below the WHO (2010) threshold. And also the analysed parameters showed seasonal variations
in concentrations from January to December either as a result of geologic factors or as a result of
anthropogenic activities of man. And it was recommended that there be a regular routine
monitoring of the various human activities along the course of the rivers and establishment of
water laboratories to test the water at least once a year in order to safeguards human health.
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CHAPHTER TWO
2.0 GEOLOGIC SETTING
Patani in Delta state lies between latitude 4o45’ to 5o45’ N and longitude 6o25’ to 6o35’ E
with an elevation of 11m by map and a probable water level of 788 meters. The area is underlain
by the deposits of the modern and Holocene delta top deposits that result in the various
physiographic landforms
The deposits of the Freshwater Swamps and Samberiro-Warri Delta plain is universally
considered to be recent expressions of a continuation of the Benin Formation; which result from
the sediment laden discharges of the River Niger that is spread on the delta by its various
tributaries. The Freshwater Swamps are typically filled by a succession of thinly bedded silts and
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clays that are interbedded with sands (Allen, 1965; Amajor 1991, Akpoborie, 2011).The
sediments are generally admixture of medium to coarse‐grained sands, sandy clays, silts and
clays that eventually settle in fluvial/tidal channel, tidal flat and mangrove swamp environments,
a process that has been ongoing since the late Quaternary and is related to interglacial marine
transgressions (Allen, 1964; Omkens, 1974; Durotoye, 1989). The soils are of a young
geological formation of the Quaternary and Recent Alluvium underlain by cretaceous sediments
and are extensively low-lying. They are usually poorly drained in most parts of the year and,
could either be classified either as hydraquents, sulfaquents or halaquept (Soil Survey Staff,
1998). It has an area of 217km2 and a population of 67,707 at the 2006 census.
2.1 OCCURRENCE OF SURFACE WATER AND GROUNDWATER
Surface water and ground water resources are present in abundance in Patani, most open
hand dug wells that were located, had a maximum depth to water of 3ft; Rainfall is averagely
high and much of the rain is lost as run off which drains by gravity to the River Forcados.
Some of it also gathers in pools and poodles all over the town from where it is either
evaporated or infiltrates into the ground as direct recharge.
Basically, the sea been a concept of groundwater occurrence, explains the ultimate
destination of rainwater either through run off or indirect infiltration and subsurface flow.
Groundwater is a very important resource which is known to occur more widely than surface
water and it forms a significant part of the water resources of the country, considering the fact of
the enormous tropical rainfall and its occurrence is in about 50% of the country, which consist of
relatively permeable rock formation that do transmit and store reasonable quantities of water.
The ratio of surface water to groundwater was put at 1:33 (Offodile, 1992).
2.2 WATER POLLUTION
Water pollution may result from many sources, including current and past oil and gas
production and related practices, agricultural activities, industrial and manufacturing
processes, commercial and business endeavors, domestic activities, and natural sources that
may be influenced by, or may result from, human activities. According to Stewart (2013) the
following are sources of ground water contamination:
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• Land Disposal of Municipal and Industrial Waste
• Sewage Treatment and Disposal
• Land Application of Liquid Wastes
• Spills and Leaks from Storage and Transport of Liquids
• Well Injection of Liquid Wastes
• Agricultural Activities
• Mining Activities
• Radioactive Waste
• Naturally Occurring Poor-Quality Water
• Surface Water and Atmospheric Contaminants
• Homes not connected to municipal sewage system usually use septic systems to dispose of
waste water from toilets and drains
As noticed during the study, the pollution of the surface water has always been
implemented by the locals (people of the area).Most of them use the side of the river as their
dumping ground for the disposal of their domestic waste. Adults and especially children were
seen defecating into the flowing river and of which may serve as a means of feeding for water
inhabitant but also deteriorate the water quality of such river; such polluted surface water
could likely evaporate to the atmosphere or also seep through pore spaces and find its way to
the subsurface, and affecting the quality of the groundwater if in excess.
Preventive measures are to be undertaken and also highlighted to the people in such a
way, by educating them about their health and environment. And also stopping any means of
their humanly activities towards the deterioration of groundwater quality in the area.
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CHAPTHER THREE
METHODOLOGY
3.1 SAMPLE COLLECTION
Sampling was done at random. Eight (8) water samples were collected from the study area,
One (1) liter container to each. Water samples were taken as follows;
1) One liter each from three (3) open hand-dug well
2) One liter each from River Forcados at three (3) different locations.
3) One liter each from two (2) boreholes.
The total of eight (8) water samples that were collected, were also been analyzed. In order
to obtain a representative sample, sample containers were firstly rinsed with distilled water and
at every water sampling location, the 1 liter sample container was pre-rinsed with the water
sample before final collection.
The sample containers were also labeled, having an initial which indicates the point of
collection and also my name(the researcher); Other details such as the time, temperature, date,
GPS readings(Elevation, longitude and latitude), sample location and the parameters
determination via analysis were written down.
3.2 SAMPLE PRESERVATION
Sample preservations are measures taken to prevent reduction or loss of target analytes.
Analyte loss can occur between sample collection and laboratory analysis because of physical,
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chemical, and biological processes that result in chemical precipitation, adsorption, oxidation,
reduction, ion exchange, degassing, or degradation. Preservation stabilizes analyte
concentrations for a limited period of time. Some samples have a very short holding time.
Also, the process of sample preservation is aimed at preventing more than 10% change in
contents between the original and preserved sample. The samples obtained from the study area
were preserved in a refrigerator at 4oC. No preservative chemical was used.
6010’ 6011’ 6012’
6010’ 6011’ 6012’
FIGURE 3.1: SAMPLE LOCATIONS SHOWN ON AN AERIAL MAP OF PATANI
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5014’5012
5014’
5013’
5012’
5013’
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Address Longitude Latitude Elevation(m) Temperature(0C)Location
One
Under the
bridge.
N05013’31.8” E006011’31.8” 11 28
Location
Two
Patani Market
river
N05013’57.9” E006011’48.6” 17 26
Location
Three
Afanaware
Quarters
N05014’06.1” E006011’42.8” 17 28
Location
Four
Hospital road
off Patani
Market
N05014’04.7” E006011’36.4” 16 28
Location
Five
Along
Ogoloma
Road by water
Mass Patani
N05012’57.3” E006011’26.4” 22 28
Location
Six
Opp. Location
Five, at the
River
N05012’59.8” 006011’31.4” 17 26
Location
Seven
Ayakpo
Compound,
Ekise Quarters
N05013’51.1” E006011’35.7” 19 26
Location
Eight
Keboh
Compound,
Ekise Quarters
N05013’52.1” E006011’34.0” 16 28
Table 3.1: SAMPLE LOCATIONS AND DETAILS
3.3 MATERIAL AND METHODS
pH DETERMINATION
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METHOD: ELECTROMETRIC METHOD
METHOD No: 4500-H+ B (Std. Method, 19th eds.; 1995)
APPARATUS:
1. pH meter
2. Beakers
3. Tissue paper
REAGENT: pH buffer 7.0 & 4.0
PROCEDURE:
Calibration of the pH meter:
I. Take the reading of the pH 7.0 and pH 4.0 standards, before calibration, record the
readings.
II. Calibrate the pH meter using the buffer 7.0 and 4.0 buffers.
III. Ensure that all buffers are at the same temperature.
IV. Rinse the electrode first with de-ionized water, and then with pH 7 buffer.
V. Place the electrode in the buffer 7, and press calibration knob on the instrument.
VI. Wait for a stable display and accept the reading by pressing enter/yes.
VII. Rinse electrode with de-ionized water and then with buffer 4.0
VIII. Place the electrode in the buffer 4.0 solution.
IX. When the display is stable, accept the reading.
X. Check to see that the slope is okay.
XI. Take the reading of the pH buffers after calibration, and record the results.
SAMPLE MEASUREMENT
i. Rinse the electrode with de-ionized water, followed by some of the sample.
ii. Shake the sample very well and place the electrode in the sample.
iii. When the reading is stable, record the sample pH.
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QUALITY CONTROL/PRECAUTIONS
1. Check the calibration standard (Buffer 7.0 & 4.0) before carrying out the analysis of sample.
2. Duplicate Sample: Analyze sample in duplicate to ascertain the precision of the analysis.
3. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer).
CONDUCTIVITY
METHOD: LABORATORY METHOD
METHOD No: -2510 B. (Std. Method, 19th edn. 1995)
METHOD No. 9050(EPA, SW 846,Vol. 1C, 3rd edn. 1986)
APPARATUS:
I. Self-contained Conductimeter, capable of measuring conductivity with an error not
exceeding 1% or 1uS/cm, whichever is greater.
II. General laboratory glassware.
REAGENTS:
1. Conductivity Water: Pass distilled water through a mixed bed de-ionizer and discard first
1L. Conductivity should be less than 1uS/cm.
2. Standard potassium Chloride (0.01M): Dissolve 0.7456g anhydrous KCl in conductivity
water and make up to 1L.
3. This solution will have a specific conductance of 1413uS/cm at 25oC. or 1000uS/cm
reference standard from Hach.
PROCEDURE:
1. Calibrate the conductivity meter using the 1000uS/cm or the 1413uS/cm, conductivity
standard.
2. Rinse the cell with one or more portion of the sample.
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3. Measure sample conductivity by dipping the cell into the sample, and note the
temperature.
4. Allow the reading to stabilize before taking the reading
5. The result in uS/cm or mS/cm would be displayed.
6. Record the reading, and convert result to uS/cm unit, if sample reading is in mS/cm by
multiplying the mS/cm reading by 1000.
QUALITY CONTROL/PRECAUTIONS:
1. Check the calibration standard, and ensure that, the recovery must be within ±10%.
2. Continuing calibration check: continuing calibration standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
3. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
4. Duplicate Sample: Analyze sample in duplicate to ascertain the precision of the analysis.
5. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer).
DISSOLVED OXYGEN (DO)
METHOD: AZIDE MODIFICATION METHOD.
METHOD No.: -4500-C. (APHA, 19TH edn. 1995)
APPARATUS:
i. 150mL DO bottles
ii. 250mL conical flask
iii. 10mL pipettes
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iv. Pipette filler
REAGENTS:
i. Manganous Sulfate Solution: Dissolve 480g MnSO4.4H2O or 400g MnSO4.2H2O, or 364g
MnSO4.H2O in distilled water, filter and dilute to 1L. The MnSO4 solution should not give
a color with starch when added to an acidified potassium iodide (KI) solution.
ii. Alkali-Iodide-Azide Reagent: Dissolve 500g NaOH (or 700g KOH) and 135g NaI (or
150gKI) in distilled water and dilute to 1L. Add 10g NaN3 dissolved in 40mL distilled
water. Potassium and Sodium salts may be used inter-changeably. This reagent should not
give a color with starch solution when diluted and acidified.
iii. Concentrated H2SO4
iv. Starch Indicator: Prepare by dissolving 2g laboratory grade soluble starch and 0.2g
salicylic acid as a preservative in 100mL distilled water.
v. Standard sodium thiosulfate titrant (0.025M): Dissolve 6.205g Na2S2O3.5H2O analytical
grade reagent, in distilled water and dilute to 1L. Standardize against 0.0021M potassium
bi-iodate solution.
vi. Standard Potassium Bi-iodate solution (0.0021M): Dissolve 812.4mg KH (IO3) 2 in
distilled water and dilute to 1L.
PROCEDURE:
i. Standardization of 0.025m thiosulfate solution: Dissolve approximately 2g KI, free from
iodate, in an Erlenmeyer flask with 100-150mL distilled water.
ii. Add 1mL 6N H2SO4 or a few drops of conc.H2SO4 and 20mL standard bi-iodate solution.
iii. Dilute to 200mL and titrate liberated iodine with thiosulfate titrant, adding starch indicator
toward end of titration, when a pale straw color is reached.
iv. When the solutions are of equal strength, 20mL of 0.025M Na2S2O3 should be required.
PROCEDURE FOR SAMPLE MEASUREMENT:
1. Collect sample into a 250mL-300mL BOD bottle.
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2. Allow the sample to overflow for 5 seconds and cork. Avoid trapping of air bubbles or
vacuum at the top of the bottle.
3. Add 1mL MnSO4 solution (Winkler A)
4. Add 1mL Alkali-Iodide-Azide solution immediately (Winkler B).
5. Stopper carefully to exclude air bubbles and mix by inverting bottle a few times.
6. Allow the floc to settle half way in the bottle, to leave the clear supernatant above the
Manganese Hydroxide floc.
7. Add 1mL Conc.H2SO4. Stopper and mix by inverting several times, until dissolution is
complete.
8. Titrate a volume corresponding to 200mL original sample after correction for sample loss
by displacement with reagents.
9. Titrate with 0.025 Na2S2O3 solution to a pale straw color. Add a few drops of starch
solution and continue titration to first disappearance of blue color.
CALCULATION:
For titration of 200mL sample: 1mL 0.025M Na2S2O3 = 1mgDO/L
If 100mL sample was titrated, multiply titre by 2.
QUALITY CONTROL/PRECAUTIONS:
1. Check the result of the standardization result for the thiosulfate, ensure that it is equal or close
to 0.025M as stated.
2. Avoid trapping of air bubbles in the bottle during this analysis.
3. Ensure that the right quality reagents are used for the analysis, if in doubt, check with the
QA/QC officer.
TOTAL DISSOLVED SOLIDS
METHOD: ELECTRICAL CONDUCTIVITY METHOD
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APPARATUS:
1. Conductivity Meter
2. General laboratory glassware.
REAGENTS:
As done in Conductivity determination.
PROCEDURE:
1. Calibrate the conductivity meter using the 1000uS/cm, conductivity standard.
2. Press the mode key until the TDS mode is displayed.
3. Rinse the probe with some portions of the sample.
4. Immerse the probe into the sample, and avoid the trapping of air bubbles around the
temperature sensor.
5. Allow the reading to stabilize before taking the reading
6. Take the reading and record it.
7. If reading is in g/L, multiply by 1000 to convert to mg/L.
QUALITY CONTROL/PRECAUTIONS:
1. Check the calibration standard, and ensure that, the recovery must be within ±10%.
2. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
3. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
4. Duplicate Sample: Analyze sample in duplicate to ascertain the precision of the analysis.
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5. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer).
TOTAL SUSPENDED SOLID (TSS)
Method: Photometric Method.
APPARATUS:
i. Hach DR 2010
ii. Blender
iii. General lab, Glassware
REAGENTS: None
PROCEDURE:
1. Enter the stored program number for suspended solids
2. Press 630 and enter.
3. Dial to 810nm using the wavelength dial.
4. Blend 500ml of sample at high speed for 2 minutes.
5. Pour the blended sample into a 600ml beaker.
6. Stir the sample and pour 25ml of blended sample into a sample cell.
7. Fill another sample cell with distilled or deionized water. Use this as blank.
8. Place the blank in the cell holder. Close the light shield.
9. Press zero.
10. Swirl the prepared sample cell to remove gas bubbles and to suspend any residue.
11. Place the prepared sample into the cell holder. Close the
light shield.
12. Press Read. The value in mg/L would be displayed.
QUALITY CONTROL/PRECAUTIONS:
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1. Always wipe the sample cell clean with soft tissue, and avoid using ordinary hand to hold the
cell, use tissue paper.
2. Set the equipment to the right wavelength.
3. Always do analysis in duplicate to check precision.
TURBIDITY
Method: Nephelometric Method
Method No.: 150.1 (EPA 600/4 – 79 – 020)
APPARATUS MATERIAL
I. Turbidimeter 2100p Hach or Filter photometer.
II. Sample tubes.
REAGENTS:
1. Stock Turbidity standard: 4000mg/L Formazin standard solution Hach. Alternatively,
Prepare as follows:
(a)Solution I: - Dissolve 5g Hydrazine sulfate (NH2) 2 .H2SO4, in dist. H2O and dilute to 400ml
in a flask. Prepare every month.
(b)Solution II: - Dissolve 50g Hexamethylene tetramine (HMTA) (CH2) 6 N4, in
Distilled water and dilute to 400mL in a volumetric. Prepare every month.
(c)Pour the two solutions into 1L volumetric flask and dilute to mark with distilled water.
(d)Let it stand for 48hrs at 250C.
(e)Mix the 4000 NTU stock solution for at least 10mins before use.
Preparation of Formazin standard solution
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Prepare 20, 100 and 800 NTU standards as follows: Dilute 1, 5 and 20ml 4000 NTU stock to
200mL in a 200mL Class A volumetric flask respectively.
Calibration of Turbidimeter
Use the above prepared standards to calibrate the equipment, starting with the 20 NTU standard.
Measurement of Sample
1. Thoroughly shake sample, wait for a while for air bubbles to disappear.
2. Clean the nephelometer sample tube with soft tissue.
3. Read turbidity directly from the instrument.
4. Results are in NTU unit.
Quality Control/Precautions:
1. Initial calibration check: The continuing calibration standard (CCS)(middle range calibration
standard) is analyzed immediately after the calibration curve to check calibration; the recovery
must be within ±10%.
2. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
3. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
4. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer).
5. Always wipe the sample cell clean with soft tissue, and avoid using ordinary
COLOR
Method: -Platinum – Cobalt Method
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Method No: -2120 B (standard methods, APHA 18th ed., 1992).
Apparatus:
I. Spectrophotometer for use at 465nm/455nm
II. General lab; Glass ware
REAGENTS:
I. Color standard solution: Pt – Co color Standard, 500 Pt – Co unit.
II. Prepare color standard solutions from the stock color standard by measuring the
appropriate volumes and making up the 50mL in a volumetric flask respectively.
Measurement of Color
Prepare a calibration curve by measuring the color of the standard solutions using the DR
2010 or DR 5000U. Plot a calibration curve and obtain a good correlation coefficient of R2 ≥
0.995.
Measurement of Sample
1. Take a portion of well-mixed sample into the required sample cell.
2. Use distilled H2O as blank to zero the equipment.
3. Insert the sample in the sample cell into the cell holder
4. The value in Pt-Co unit would be displayed.
5. For true color, use filtered sample for the analysis to remove suspended particles.
Quality Control/Precautions:
1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Initial calibration check: The continuing calibration standard (CCS)(middle range calibration
standard) is analyzed immediately after the calibration curve to check calibration, The recovery
must be within ±10%.
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3. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once every 10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the calibration curve is constant through the run.
4. Matrix spike/matrix spike duplicate: This is analyzed once for every 20 samples or for every
sample batch. The % recovery should be ±15% for it to be accepted.
5. Duplicates: Analyze duplicate sample to check the precision of the analysis, and it must be
within the acceptable limit for the laboratory
ALKALINITY
METHOD: -TITRATION METHOD.
METHOD No.: -2320 – Alkalinity – B (Standard Methods, 1995)
Apparatus:
I. Burettes (50mL)
II. Pipettes
III. Retort Stand
IV. General lab. Glassware
Reagents
1. Mixed bromocresol green-methyl red indicator solution: Prepare by mixing 0.1g bromocresol
green and 0.02g methyl red in 100mL isopropyl alcohol.
2. Phenolphthalein indicator solution: Prepare by dissolving 5g phenolphthalein in 500mL
isopropyl alcohol and add 500mL distilled water. Mix well.
3. Sodium carbonate solution: - 0.05N. Dry 3 to 5g primary Standards of Na2CO3 at 2500C for 4
hours and cool in a desiccator. Weigh 2.5± 0.2g, transfer to a 1L volume flask, fill to the mark
with distilled Water, dissolve and mix reagent. Stabilize for 1 week.
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4. Standard sulfuric acid, 0.1N: Prepare by adding 2.8ml of conc. H2SO4 to 500ml distilled H2O
in a 1L volume flask. Make it up the mark. Standardize against 40.0mL of 0.05N Na2CO3
solution with about 60mL of H2O.
Normality N = A x B
53.0 x C
Where:
A = g Na2CO3 weighed into 1L flask
B = mL of Na2CO3 used for standardizing.
C = mL acid used.
5. Standard H2SO4 titrant; - 0.02N – Dilute 200mL 0.1N Std acid to 1L with distilled or
deionized water. Standardize using 15mL 0.05N Na2CO3 solution. Calculate normality as
above.
Procedure:
1. Take 50 or 100ml of sample in a 250ml Erlenmeyer flask.
2. Add 2 – 3 drops of phenolphthalein indicator solution. If no pink color develops, there is
no phenolphthalein alkalinity, but, if pink color develops, titrate with the standard acid to
a colorless end point. Note the reading.
3. Add 2 – 3 drops of methyl orange or mixed indicator solution.
4. Titrate to a golden yellow end point or disappearance of the green color. Note the reading.
Calculation:
Alkalinity, mg CaCO3/L =A x N x 50,000ml sample
Where:
A = mL standard acid used
N = normality of standard acid.
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Quality Control/Precautions:
1. Check the result of the standardization result for the standard acid, ensure that it is equal or
close to 0.02N as stated.
2. Always do analysis in duplicate to check precision.
3. Ensure that the right quality reagents are used for the analysis, if in doubt, check with the
QA/QC officer.
DETERMINATION OF BICARBONATE
Mg/l alkalinity x 1.22= Bicarbonate (HCO3).
Bicarbonate (HCO3) is done via calculation from alkalinity obtained from the regression
equation.
CHLORIDE
METHOD: ARGENTOMETRIC METHOD
METHOD No: 4500-Cl- B. (APHA, 19th edition. 1995)
Apparatus:
I. 250mL Erlenmeyer Flask
II. 50mL Burette
III. Retort Stand with clamp.
Reagents:
I. Potassium Chromate Indicator Solution: Dissolve 50g K2CrO4 in a little distilled water.
Add AgNO3 solution until a definite red precipitate is formed. Let stand 12hrs and filter,
dilute to 1L with distilled water.
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II. Standard Silver Nitrate (AgNO3) titrant; 0.0141N: Dissolve 2.395g AgNO3 in distilled
water and dilute to 1L. Standardize against 10mL NaCl by the procedure described below.
Store in amber colored bottle.
III. Standard Sodium Chloride; 0.0141N: Dissolve 824mg NaCl (Dried at 140oC) for 1hr in
distilled water, dilute to 1L. (1mL = 500ug Cl-)
IV. Sodium Hydroxide; NaOH (1N): Prepare by weighing 40g analar grade NaOH, dissolve in
little water and transfer to 1L volumetric flask.
V. Standard Sodium Chloride Solution (NaCl); 1000mg/L: Dissolve 1.648 NaCl analar
grade, dried at 140oC for 1hr, in distilled water, and dilute to 1L with distilled water.
(1mL = 1.0mg Cl-)
VI. Aluminium Hydroxide Suspension: Dissolve 12.5g Aluminium Potassium Sulfate,
Aluminium Potassium (SO4)2.12H2O or AlNH4 (SO4)2.12H2O, in 1L of distilled water.
Warm to 60oC and add 55mL Conc. Ammonium Hydroxide (NH4OH) slowly with
stirring. Let stand for 1hr, transfer to a large bottle, and wash precipitate by successive
additions, with thorough mixing and decanting with distilled water, until free from
chloride. When freshly prepared, the suspension occupies a volume approximately, 1L.
Procedure:
I. Preparation of Calibration Standards:
II. Prepare a calibration standard to cover the range 100ppm to 1000ppm, by taking the
appropriate volume of the stock chloride standard and diluting to volume in a 100mL
flask.
Procedure for Calibration Standards:
I. Take 100mL of the standard or a suitable portion diluted to 100mL.
II. Adjust pH to between 7-10 with 1N NaOH or 1N H2SO4.
III. Add 1mL K2CrO4 indicator.
IV. Titrate against standard AgNO3 titrant to a pinkish-yellow end-point. Establish a reagent
blank value by titrating distilled water as above.
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V. Calculate the concentration of chloride in the various standards as follows; mg Cl-/L = (A-
B) x N x 35450mL of Sample
Where:
A = volume of 0.0141N AgNO3 used for titration
B = Volume of AgNO3 used for Blank titration (Should not exceed 0.3mL)
N = Normality of AgNO3
VI. Plot a calibration graph, by plotting the calculated values against the corresponding
concentration. Obtain a regression equation, and the R2 value should be ≥0.995.
Sample Titration:
1. Take 100mL of sample or a suitable volume made up to 100mL.
2. Adjust pH to 7-10 as above.
3. Add 1mL K2CrO4 indicator solution.
4. Titrate with standard AgNO3 titrant to a pinkish end-point.
Calculation:
As done in the standard above. Obtain the chloride concentration by inserting this value in
the regression equation.
Quality Control/Precautions:
1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Check the result of the standardization result for the standard silver nitrate, ensure that it is
equal or close to 0.0141N as stated.
3. Always do analysis in duplicate to check precision.
4. Ensure that the right quality reagents are used for the analysis, if in doubt, check with the
QA/QC officer.
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SULPHATE
METHOD: TURBIDIMETRIC METHOD
METHOD No: 375.4 (EPA – 600/4 – 79 – 020).
Apparatus:
I. Magnetic Stirrer
II. Spectrophotometer for use at 450nm/ Turbidimeter
III. Spatula
IV. General laboratory Glassware
Reagents:
I. Conditioning reagent: - slowly add 30ml of concentrated HCL to 300ml distilled H2O,
100ml 95% ethanol or isopropyl alcohol, and 75g NaCl in a container. Add 50ml glycerol
and mix using magnetic stirrer.
II. Barium chloride, BaCl2 crystals 20 – 30 mesh.
III. Standard Sulfate Solution 100ppm: - Dissolve 0.1479g anhydrous sodium sulfate
(Na2SO4) analar grade in distilled H2O and dilute to 1L. (1mL = 0.1mgSO42ˉ)
Procedure:
1. Preparation of calibration standard.
2. Prepare calibration by diluting the 100mg/L standard Sulfate solution. Prepare standards
in the range 0 – 40mg/L in 100mL volume flask from the 100mg/L standard solution. If a
higher calibration standard set is desired, prepare a 1000mg/L standard solution and
prepare calibration standard of 0 – 1000ppm from it.
3. Measurement of Barium Sulfate Turbidity
4. Take 25ml of blank and standards into an Erlenmeyer flask.
5. Add 1mL conditioning reagent
6. Mix properly
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7. Add a measuring spoonful of BaCl2 crystals and stir for 1min.
8. Read the absorbance at 450nm at 30seconds intervals for 4minutes.
9. Record the maximum reading obtained in the 4-minutes period.
10. Prepare a calibration curve by plotting sulfate standard concentration against absorbance
readings.
11. Calculate the correlation coefficient (R2 value) and it must be ≥ 0.995. Else, prepare
another batch of standards and start all over again.
Analysis of Samples
1. Take 25ml of well mixed sample into an Erlenmeyer flask.
2. Follow steps 2 – 6 above.
3. To compensate for sample turbidity, use a portion of the well mixed sample as blank for
each of the samples, without adding BaCl2. Subtract the value from the treated sample
value.
Calculation:
Calculate sample result from the calibration curve using linear regression equation.
Quality Control/Precautions:
1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Initial calibration check: The continuing calibration standard (CCS) (middle range calibration
standard) is analyzed immediately after the calibration curve to check calibration, the recovery
must be within ±10%.
3. Continuing calibration check: Continuing calibration standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
4. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
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and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
5. Matrix spike/matrix spike duplicate: This is analyzed once for every 20 samples or for every
sample batch. The % recovery should be ±25% for it to be accepted.
6. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer).
7. Duplicate sample: Analyze duplicate sample to check the precision of the analysis, and it must
be within the acceptable limit.
AMMONIA-NITROGEN IN WATER
METHOD: DIRECT NESSLERIZATION METHOD
METHOD NO: 4500 – NH3C (STD Methods, 17 ed. 1989).
METHOD NO: 350.2 (EPA – 600/4 – 79 – 020)
APPARATUS:
I. Standard acid washed glass wares.
II. Spectrophotometer or Hach 4000U for use at 425nm
Reagents:
Nessler Reagent: -
I. Dissolve 100g HgI2 and 70g KI in a small quantity of water
II. Dissolve 160g NaOH in 500ml water with stirring. After dissolution, cool to room temp.
III. Add slowly with stirring, solution A to solution B and dilute to IL.
IV. Store in rubber – stoppered borosilicate glass bottle and protect from sunlight.
V. The solution is stable for up to 1 year under normal laboratory conditions.
VI. Stock NH3 Solution – 1000ppm NH3-N
VII. Dry NH4Cl in oven at 1000C for 1hr.
32
ZPreparation of Calibration Curve
1. Prepare calibration curve in 50ml final volume with a range of 0.1 to 1.0ppm or 1.0 to
ppm NH3-N, by diluting the appropriate volumes to 50ml respectively. A six-point
calibration or 5 points calibrations would be required.
2. Transfer blanks and standards to 125ml Erlenmeyer flask.
3. Add 1mL nessler reagent and mix well.
4. Let reaction proceed for 10mins.
5. Read absorbance at 425nm using reagent blank for zeroing the instrument.
6. Prepare a calibration curve; check its acceptance by calculating the correlation coefficient.
Sample Measurement
1. Take 50ml of sample or a smaller size dilute to 50ml.
2. Use the same procedure for color development as described above for the standards.
3. Calculate the concentration of NH3-N and repeat in mg/L. The ammonia concentration
measured is calculated by linear regression calculation if other spectrophotometer is used in the
analysis. While DR 4000U gives the result automatically.
Quality Control/Precautions:
1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Initial calibration check: The continuing calibration standard (CCS)(middle range calibration
standard) is analyzed immediately after the calibration curve to check calibration. The recovery
must be within ±10%.
3. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
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4. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
5. Matrix spike/matrix spike duplicate: This is analyzed once for every 20 samples or for every
sample batch. The % recovery should be ±20% for it to be accepted.
6. Wash all glassware with chromic acid to avoid contamination.
7. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer)
NITRATE-NITROGEN (NO3-N) IN WATER
Method: Cadmium Reduction Method
Method No: 4500-NO3- E (APHA, 19th edn. 1995)
Apparatus:
i. Spectrophotometer for use at 410nm
ii. Acid washed glassware
Reagents:
i. Nitraver 5 Powder Reagent
ii. Stock NO3-N, 1000 mg/l: - Dry potassium nitrate (KNO3) at 105oC for 24hrs.
iii. Dissolve 7.218g in distilled water and dilute to 1 L Preserve with 2ml chloroform per liter.
The solution is stable for at least 6 months. Store in a refrigerator.1ml = 1mg (1000ug)
NO3-N
iv. Standard NO3-N solution, 10mg/l: - Measure 10ml stock NO3-N solution and dilute to 1 L.
Preserve with 2ml of chloroform per 1 L Solution is stable for 3 months. Store in
refrigerator.1ml=0.01mg(10ug) NO3-N
Procedure:
Preparation of calibration standards:
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All the glassware to be used must be thoroughly washed and treated with chromic acid.
1. Prepare calibration standards to cover the range, 0 to 1.0 mg/l by diluting appropriate volume
to 50ml.
2. Pipette 10ml of each standard into different Erlenmeyer flask
3. Add one sachet of the Nitraver 5 powder pillow
4. Shake thoroughly for 1min and allow to settle for 5minutes.
5. An amber colour would develop.
6. Read the absorbance at 410nm
8. Read of the absorbance on DR 2010 or 4000U at 410nm.
9. Use distilled H2O as blank.
10. Plot the calibration graph and check its acceptance by calculating the Correlation
Coefficient (R2 value should be ≥ 0.995).
Determination of sample
1. Take 10ml of sample into an Erlenmeyer flask.
2. Follow steps 3- to 9 above.
Calculation: -
Read the Conc. of the sample from the calibration curve using the regression equation.
Quality Control/Precautions:
1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Initial calibration check: The continuing calibration standard (CCS)(middle range
calibration standard) is analyzed immediately after the calibration curve to check
calibration, The recovery must be within ±10%.
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3. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once
every 10 samples or 20 samples, if samples are many. The purpose of the CCV is to very
that the calibration curve is constant through the run.
4. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples
if samples are many. Since the reference standard is prepared from source different from
the CCS and calibration, this is used to verify that the CCS and calibration standards are
actually at the concentrations claimed by the analyst.
5. Matrix spike/matrix spike duplicate: this is analyzed once for every 20 samples or for
every sample batch. The % recovery should be ±20% for it to be accepted.
6. Wash all glassware with chromic acid to avoid contamination.
7. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer)
8. Duplicate analysis: Analyzed once in every sample batch. The calculated precision must
be within the in-house established limit.
NITRITE-NITROGEN (NO2-N) IN WATER
METHOD: COLORIMETRIC METHOD (NED)
Method No. 354.1 (EPA – 600/4 – 79 – 020)
Method No: 4500-NO2 B (Standard Method, 1995)
Apparatus:
I. Spectrophotometer for use at 543nm
II. Acid washed glass wares.
Reagents:
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I. Color Reagent: To 800mL dist. H2O add 100mL 85% phosphoric acid and 10g
sulfanilamide. After sulfanilamide dissolves completely, add 1g NED dilute
hydrochloride and mix to dissolve, then dilute to 1L with distilled H2O. Solution is stable
for about a month when stored in a dark bottle in a refrigerator.
II. Stock NO2-N Solution (100mg/L) – use 0.1493g dried sodium nitrite (dried in desiccator
for 24 hours), dissolved and diluted to 1L. Preserve with 1mL chloroform. Store at 40C.
Solution is stable for 3 months.
1mL = 0.1mg NO2-N (1mL = 100ug).
III. Standard NO2-N solution, 1mg/L – use 10ml stock solution diluted to 1L. Prepare daily.
1mL = 0.001mg NO2-N (1ml = 1ug)
Procedure:
1. Preparation of calibration standards:
2. Prepare calibration standards to cover the range 0 – 0.2ppm by diluting the appropriate
volumes to 50mL final volumes respectively.
3. Add 2ml color reagent to each std. Mix well. Do same to blank.
4. Allow color to develop for at least 15 minutes.
5. Read absorbance at 543nm using DR 2010 or DR 4000U.
6. Prepare a calibration curve and check its acceptance by calculating the correlation
coefficient.
Sample Analysis:
Analyze sample using 50ml or Aliquots diluted to 50ml as described for the standards, step 2 to
step 4.
Calculation: Compute sample concentration from the curve by using the linear regression
equation.
Quality Control/Precautions:
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1. Check the calibration curve, and ensure that, the R2 value is ≥0.995
2. Initial calibration check: The continuing calibration standard (CCS)(middle range calibration
standard) is analyzed immediately after the calibration curve to check calibration, The recovery
must be within ±10%.
3. Continuing calibration check: Continuing Calibration Standard (CCS) is analyzed once every
10 samples or 20 samples, if samples are many. The purpose of the CCV is to very that the
calibration curve is constant through the run.
4. Reference (independent) Standard: This is analyzed once every 10 samples or 20 samples if
samples are many. Since the reference standard is prepared from source different from the CCS
and calibration, this is used to verify that the CCS and calibration standards are actually at the
concentrations claimed by the analyst.
5. Duplicates: This is done in order to establish the preciseness of the analysis.
6. Wash all glassware with chromic acid to avoid contamination.
7. Always use the specified grade of reagent, and ensure that it has passed the QC check
(confirm that from the QA/QC officer)
DETERMINATION OF EXCHANGEABLES Ca, Mg, K, Na
Apparatus:
I. 100ml volumetric flask
II. Flame photometer (Buck Scientific PEP-7)
REAGENTS: Concentrated Nitric acid
Procedure:
I. To a 100ml sample, add 1ml of nitric acid.
II. Shake vigorously and allow to stand for 10 minutes. Sample is ready for flame
emission spectrophotometer (FES) analysis.
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Instrument set-up:
1. Turn on FES.
2. Allow system to warm up to 30 minutes.
3. Return knob to ABS.
4. Set wavelength to obtain a maximum energy reading and optimize by ensuring that the
Acetylene: Air ratio is 1:8, which is 40 psi.
5. Turn on flow of air and acetylene
6. Ignite and aspirate distilled water for about 5 minutes to warm up system.
7. Adjust the fuel flow so that the ABS reading for distilled water blank is minimized to give
maximum sensitivity. Note: Do not adjust the air flow.
8. Aspirate a solution of the element (the highest concentration) and adjust the burner height
and position to get a maximum ABS reading.
9. Check the distilled water to see if it is still close to Zero (± 0.005).
10.Adjust the Nebulizer when necessary to get a stable maximum signal.
11.Check the wavelength to get a maximum signal.
CALIBRATION AND SAMPLE ANALYSIS
1. Make a five point calibration standard and calibrate the system (refer to calibration range
in Buck Scientific by A.A Cookbook).
2. Begin the analysis by aspirating the sample blank.
3. Zero the energy, and then aspirate the standard and samples recording the ABS.
4. Check standard and blank intensities throughout the analysis (say every 10 samples)
QUANTIFICATION
Plot a calibration curve and obtain regression equation.
Use the ABS to calculate the concentration of the analyte from the regression equation.
Metal concentration in mg/l= (A x B)/Z sample.
Where A = Concentration of metal in digested solution.
B = Final concentration of metal in digested solution.
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Z = Sample weighed.
QUALITY CONTROL/PRECAUTIONS:
1. The pH must be calibrated when used for adjustment.
2. All glassware must be washed and rinsed thoroughly with distilled water.
3. The flame photometer must be checked and calibrated.
ANALYSIS OF HEAVY METALS
Heavy metal Analysis with GBC scientific AAS SENSAA 635
Apparatus:
1. Hot plate
2. 250ml Pyrex conical flask acid washed and rinsed with distilled water.
3. A 100ml volumetric flask polypropylene or suitable one.
Reagents:
1. Perchloric acid-1
2. Nitric acid-2
3. Sulphuric acid-2
Procedure for water sample preparation
1. Add 2ml (1+1) nitric acid to the beaker containing 100ml of sample.
2. Place the beaker on a hot plate for solution evaporation.
3. Allow the beaker to cool. Quantitatively transfer the sample solution the volumetric flask.
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4. Allow any undissolved materials to settle overnight, or centrifuge a portion of the prepared
sample until clear. If after centrifuge and the sample contain suspended solids, a portion of the
sample may be filtered prior to analysis. All analysis should be performed as soon as possible
after the completed preparation.
Instrument set-up:
1. Prepare sample for analysis following digestion procedure (refer to SOP/Quality manual.)
2. Power on AAS System and place the element Hollow-Cathode lamp in lamp holder.
3. Allow system to warm up for about 30mins
Set Operating conditions as follows:
1. Set Manual Zero mode and Auto Zero Button out
2. Turn selection knob on PMT and adjust PMT volts using the ABS knob to 250 - 350
Volts.
3. Return knob to ABS
4. Set Wavelength to obtain a maximum energy reading and optimize by adjusting the
vertical/horizontal lamp mount control
5. Push Auto Zero Button IN to set Mode to Zero.
6. Ensure that the Acetylene: Air ratio is 1:8 i.e. 5Psi: 40 psi
7. Turn on flow of air and Acetylene
8. Ignite and aspirate distilled water for about 5mins to warm up system
9. Adjust the fuel flow so that the ABS reading for distilled water blank is minimized to give
maximum sensitivity. Note : do not adjust the air flow
10.Auto Zero the signal by pushing the zero button.
11.Aspirate a solution of the element (the highest concentration) and adjust the burner height
and position to get a maximum ABS reading
12.Check the distilled water to see if it is still close to Zero (± 0.005)
13.Adjust the Nebulizer when necessary to get a stable maximum signal
14.Check the wavelength to get a maximum signal
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Calibration and Sample Analysis
1. Make a five point calibration standard and calibrate the system (refer to calibration range
in Buck Scientific by A.A. Cookbook)
2. Begin the analysis by aspirating the sample blank
3. Zero the energy, and then aspirate the standards and samples recording the concentration
of the analyte in computer readout.
4. Check standards and blank intensities throughout the analysis (say every 10 samples).
TABLE 3.2: SAMPLE LOCATION AND DETERMINATION OF SOURCES WITHIN
THE STUDY AREA
LOCATION SAMPLE NO DESCRIPTION OF SAMPLE
Under Patani Bridge SW1 Sample from River
Patani Market SW2 Sample from River
Afanaware Quarters, along
Patani Market Road
WW1
Sample from dug well
Hospital Road off Patani
Market Road. WW2
Sample from dug well
Along Ogoloma Road by
Water mass Patani. BHW1/JACK
Bore hole Sample
Opp. Ogoloma Road by
water mass Patani.
SW3
Sample from River
Ayakpo Comp. Ekise
Quarters.
BHW2
Bore hole Sample
Keboh Comp. Ekisa
Quarters WW3
Sample from dug well
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CHAPTER FOUR
4.0 PRESENTATION, INTERPRETATION AND DISCUSSION OF RESULTS
4.1 PRESENTATION OF RESULTS
The portability or purity of water for many domestic and other purposes, mostly drinking is
determined by comparing the results of analysis of the water with a standard reference table that
is widely accepted. There has been different standard reference table that has been put together
by different countries to their own satisfaction or suitability, but the most generally accepted
standard is the one written by the World Health Organization (WHO). Due to this knowledge,
the W.H.O standard has always been used to estimate the portability of waters.
Seen below, are the results obtained from the various water sample analyzed and
compared with the W.H.O standard for portability. The table shows the results of groundwater
(Dug wells and Bore holes) samples and Surface water (River) Samples.
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Z TABLE 4.0: PHYSIOCHEMICAL ANALYSIS OF WATER SAMPLES
44
SW 1 SW2 SW3 WW1 WW2 WW3 BW1 BW2 WHO (2011)
ph6.51 6.91 6.15 5.50 5.96 6.08 4.68 4.60 6.5-8.5
Conductivity(µs/cm)26.00 42.80 56.90 433.00 183.00 291.00 306.00 312.00 --
TDS(mg/l)13.00 23.60 31.40 239.10 91.50 160.60 153.00 156.00 600
TSS(mg/l)174.00 21.00 10.00 14.30 13.00 10.3 7.50 4.00 NA
DO(mg/l)5.4 5.2 5.4 4.6 4.8 4.8 4.8 4.4 --
Turbidity(NTU)248.00 23.80 12.60 31.38 22.17 29.50 11.81 6.23 5
Color(pt/co)301.00 18.30 22.30 19.21 17.00 15.31 1.20 1.20 15
Alkalinity(mg/l)20.00 28.00 25.50 53.50 55.00 35.50 44.00 21.00 100
Bicarbonate(mg/l)24.4 34.16 31.11 65.27 67.1 43.31 53.68 25.62 --
Chloride(mg/l)9.62 15.84 21.05 160.21 67.71 107.67 113.22 115.44 250
Sulphate(mg/l)1.27 0.89 4.71 7.11 10.04 8.03 11.06 11.26 250
Ammonia(mg/l)0.37 0.38 0.08 1.71 0.19 0.328 0.10 0.08 1.5
Nitrate(mg/l)0.40 1.56 1.37 1.77 0.48 4.551 0.14 0.11 50
Nitrite(mg/l)0.06 0.08 0.06 0.02 0.25 0.065 0.09 0.18 3
Sodium(mg/l)5.532 9.106 12.106 92.128 38.936 61.915 65.106 66.383 200
Potassium(mg/l)2.600 4.280 5.690 43.300 18.300 29.100 30.600 31.200 NA
Magnesium(mg/l)2.889 4.756 6.322 48.111 20.333 32.333 34.000 34.667 30
Calcium(mg/l)3.714 6.114 8.129 61.857 26.143 41.571 43.714 44.571 75
Cadmium(mg/l)<0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 0.003
Lead(mg/l)0.170 0.173 0.171 0.146 0.130 0.133 0.100 0.060 0.01
Zinc (mg/l)0.370 0.367 0.381 0.312 0.300 0.309 0.110 0.080 0.05
Copper(mg/l)4.610 3.902 4.617 0.721 0.720 0.217 0.600 0.200 2
Iron(mg/l 0.690 0.712 0.696 0.152 0.140 0.144 0.90 0.040 0.3
ZTABLE 4.2: COMPARISON BETWEEN THE MEAN VALUES FOR EACH CATEGORY WITH W.H.O STANDARD
KEY;
SW:-Surface water
BW:-Borehole water
WW:-Well water
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Dug well Bore hole River WHO Std.
pH 5.85 4.64 6.52 6.5-8.5
Conductivity(µs/cm) 302.3 4.6 41.9 --
TDS(mg/l) 163.7 154.5 22.7 600
TSS(mg/l) 12.5 5.8 98.3 NA
DO(mg/l) 4.7 4.6 5.3 --
Turbidity (NTU) 27.7 9.02 94.8 5
Color (pt/co) 17.2 1.2 113.9 15
Alkalinity (mg/l) 48 32.5 24.5 100
Bicarbonate (mg/l) 58.6 39.7 29.9 --
Chloride (mg/l) 111.9 114.3 15.5 250
Sulphate (mg/l) 8.4 11.2 2.29 250
Ammonia (mg/l) 0.7 0.09 0.3 1.5
Nitrate (mg/l) 2.3 0.1 1.1 50
Nitrite (mg/l) 0.1 0.14 0.1 3
Sodium(mg/l) 64.3 65.7 8.9 200
Potassium(mg/l) 30.2 30.9 4.19 NA
Magnesium(mg/l) 33.6 34.3 4.7 30
Calcium(mg/l) 43.2 44.1 6.0 75
Cadmium(mg/l) <0.001 <0.001 <0.001 0.003
Lead(mg/l) 0.1 0.08 0.2 0.01
Zinc(mg/l) 0.3 0.1 0.4 0.05
Copper(mg/l) 0.6 0.4 4.4 2
Iron(mg/l) 0.14 0.1 0.7 0.3
Z4.2 INTERPRETATION OF RESULTS
THE WATER CHEMISTRY
Generally as discovered via analysis, pH values ranges from 6.15 to 6.91 for surface water,
5.50 to 6.08 for dug well water and 4.60 to 4.68 for borehole water; the both groundwater can be
said to be slightly acidic or corrosive because it has an average pH of 4.64 for borehole water
and 5.85 for dug well water. This conform the absence of carbonate in solution. The average pH
in surface water is 6.52 and can be said to be almost neutral and fall within the W.H.O Standard.
The conductivity is an indication of ionic solute; from the analysis, the conductivity is
higher in groundwater samples than the surface water sample, by this notice, it indicates that the
groundwater has a higher ionic solute than the surface water. The conductivity of Total dissolved
solid is related to the conductivity of the sample.
The dissolved oxygen content of water is influenced by the source, raw water temperature,
treatment and chemical or biological processes taking place in the distribution system. The
average DO for dug well water is 4.7mg/l, borehole water is 4.6mg/l and surface water 5.3mg/l.
However, the depletion of dissolved oxygen in water supplies can encourage the microbial
reduction of nitrate to nitrite and sulphate to sulphide. It can also cause an increase in the
concentration of ferrous iron in solution. No health- based guideline value is recommended. The
various DO values for all water samples are not higher than 5.5mg/l and at such can encourage
the microbial reduction in nitrate to nitrite and sulphate to sulphide.
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Table 4.3 Comparison between the Total dissolved Solid concentration and Conductivity
Sample location TDS(mg/l) Cond.(µs/cm)
WW1 239.10 433.00
WW2 91.50 183.00
WW3 160.60 291.00
BH1 153.00 306.00
BH2 156.00 312.00
SW1 13.00 26.00
SW2 23.60 42.80
SW3 31.40 56.90
The palability of water with a total dissolved solids (TDS) level of less than 600 mg/l is
generally considered good; in the study area, the average TDS for surface water is 22.7mg/l,
borehole water is 154.5 and dug well water is 163.7, all are less than 600mg/l. The Total
dissolved solids (TDS) and Total suspended solid (TSS) makes up the Total Solid Concentration.
The analysis shows that the concentration of TDS is greater than TSS except for the first surface
water sample having a high TSS than TDS, of which is an indication that most of the sediment in
it are carried as dissolved solids. The solid may be as a result of land erosion, dumping of
commercial and municipal waste or soil leaching. An increase in TDS equally brings about an
increase in conductivity.
The concentration of TSS ranges from 10.00mg/l to 174.00mg/l for surface water, 10.3mg/l
to 14.30mg/l for dug water and 4.00 to 6.50mg/l for borehole water, of which can be likely
accepted because there is no applicable limit.
The turbidity concentration in surface water ranges from 12.60mg/l to 248.00mg/l, as
analysed, all surface water samples have high turbidity which may be as a result of particulate
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matter of many types and is more likely to include attached microorganisms that are a threat to
health. Turbidity concentration in dug wells ranges from 22.17mg/l to 31.38mg/l and for
borehole, 4.00 to 7.50mg/l. All concentrations are above W.H.O guidelines.
Turbidity in some groundwater sources is a consequence of inert clay of chalk particles
in the precipitation of non-soluble reduced iron and other oxides when water is pumped from
anaerobic waters.
For colour, the average value for surface water is 113.9pt/co and of which is above the
WHO limit, dug well water samples has an average of 17.2pt/co and it does not fall within the
accepted limit, all borehole water samples are below 15.31pt/co and can be said to be accepted.
Both groundwater samples have no visible colour except the surface water. Colour in drinking-
water is usually due to the presence of coloured organic matter (primarily humic and fulvic
acids) associated with the humus fraction of soils.
The highest colour concentration in the first surface water sample is strongly influenced by
the presence of iron and other metals, either as natural impurities or as corrosion products, it may
also be as a result from the contamination of the source with industrial effluents and also may be
an indication of a hazardous situation.
The alkalinity concentration ranging between 20.00mg/l to 55.00mg/l in the study area lies
within the WHO limit of 100mg/l (WHO 2011)
Bicarbonate concentration for both groundwater and surface water in the study area ranges
from 24.4mg/l to 67.7mg/l and of which cannot be determined of its effect, but can likely be
accepted and fall within the acceptable WHO limit.
A high concentration of chloride gives a salty taste to water and of which in excess are
increasingly likely to be detected by taste. The chloride concentration of both surface water and
ground water in the study area ranges from 9.62mg/l to 160.21mg/l of which falls within the
WHO limit.
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The presence of sulphate in drinking water can cause noticeable taste, and very high level
might cause a laxative effect to human health when taken as drinking water; these may vary with
the nature of the associated cation, all surface water and ground water sulphate concentration
ranges from 0.89mg/l to 11.26mg/l and falls within the WHO limit.
Ammonia concentration in the study area ranges from 0.08mg/l to 1.71mg/l for both surface
water and groundwater; all conforms to the WHO standard; the WHO natural levels in
groundwater are usually below 0.2mg of ammonia per litre. However, ammonia does not react
with chlorine to reduce free chlorine and to form Chloramines.
Nitrate and nitrite are naturally occurring ions that are part of the nitrogen cycle. The
nitrate ion (NO3-) is the stable form of combined nitrogen for oxygenated system, although it is
chemically unreactive, but can be reduced by microbial actions. The nitrite ion (NO -2) contains
nitrogen in a relatively unstable oxidation state. Chemical and biological processes can further
reduce nitrite to various compounds or oxidize it to nitrate.
Nitrate can reach both surface water and groundwater as a consequence of agricultural
activity (including excess application of inorganic nitrogenous fertilizers and manures). The
nitrate is taken up by plants during their growth and used in the synthesis of nitrogenous
compounds. The natural nitrate concentration in groundwater under aerobic condition is a few
milligrams per litre and depends strongly on the soil type and on the geological situation.
The nitrate ion concentration in both surface water and groundwater ranges from 0.11mg/l
to 4.551mg/l and of which falls within the WHO limit. Also the nitrite ion concentration in both
surface water and groundwater ranges from 0.006mg/l to 0.25mg/l and also falls within the
WHO limit.
The concentration of sodium ranges from 5.532mg/l to 92.128mg/l, this conforms to the
WHO standard; hence water in the study area can be used for both domestic and industrial
purposes. The high proportion of sodium concentration in all boreholes and the first and third
dug well water samples could be as a result of the associated anions in the water and its
temperature.
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Potassium concentration in the study area are, 2.60mg/l to 5.69mg/l for surface water,
18.30mg/l to 43.30mg/l for the dug well water and 30.60mg//l to 31.20mg/l for borehole water.
The surface water and borehole water are of lesser concentration unlike the dug well water that
is much higher. Although potassium may cause some health effects in susceptible individuals,
potassium in take from drinking-water is well below the level at which adverse health effect may
occur. Potassium intoxication by ingestion is rare, because potassium is rapidly excreted in the
absence of pre-existing kidney damage and because large single doses usually induce vomiting
(Gosselin. Smith/Hodge, 1984). The potassium concentration in the study area all lies within the
WHO standard.
The concentration of calcium in all water samples, ranges from 3.7mg/l to 61.86mg/l and
falls within the WHO standard. A higher concentration of calcium and magnesium causes
hardness and is usually indicated by precipitation of soap scum.
The concentration of magnesium content in both surface water and ground water in the study
area range from 2.889mg/l to 48.11mg/l and it falls within the WHO standard.
The lead concentration in the study area ranges from 0.060mg/l to 0.173mg/l for both
surface water and groundwater and are above the WHO standard. The primary source of lead in
the study area can be from service connections and plumbing in buildings; its lead concentration
can also vary according to the period in which the water has been in contact with the lead-
containing materials.
Cadmium concentration for both surface water and groundwater are below 0.001mg/l and are
known to fall within the WHO standard.
Zinc concentration for surface water ranges from 0.36mg/l to 0.37mg/l, 0.140mg/l to
0.152mg/l for dug well water and 0.040mg/l to 0.110mg/l for borehole water, all are above the
WHO standard.
Zinc is an essential trace element found in virtually all food and potable water in the form of
salts or organic complexes; although levels of zinc in surface water and groundwater normally
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do not exceed 0.01mg/l and 0.05mg/l, respectively, concentration in tap water can be much
higher as a result of dissolution of zinc from pipes.
The iron concentration for all groundwater ranges from 0.040mg/l to 0.152mg/l, falls
within the WHO standard and are acceptable, except that for surface water that ranges from
0.690mg/l to 0.712mg/l which is higher and can stain laundry and plumbing fixtures; there is
usually no noticeable taste at iron concentration below 0.3mg/l although turbidity and colour
may develop.
Copper concentration for groundwater (0.2mg/l to 0.7mg/l) falls within the acceptable
WHO standard. The concentration of copper in surface water ranges from 3.9mg/l to 4.6mg/l
and is above the WHO standard. The occurrence of copper in surface water may arise from the
corrosive action of water leaching copper from copper pipes in bridges. High levels of dissolved
oxygen have been shown to accelerate copper corrosion in some cases. Concentration can vary
significantly with the period of time the water has been standing in contact with the pipes.
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CHAPTER FIVE
5.0 SUMMARY AND CONCLUSION
The quality of water cannot be over emphasized. Researchers all over the world have always continued in the explanation of water and its quality. The quality of groundwater and surface water from parts of Patani, Delta state was analyzed to know the status of its physical, chemical, and biological properties to give an insight of its quality which can be linked to its various uses, such as domestic, agricultural and industrial purposes; and with the World Health Organization (W.H.O) water guideline 2011 fourth edition, comparisons and standardization were made with the data obtain from the analysis carried out on the eight water samples.
In accordance with the result obtained, it was discovered that about fifteen analysed parameters fell within the W.H.O standard for domestic use, while others were above. The groundwater can be said to be slightly acidic or corrosive
as indicated by the pH values while the surface water can be said to be almost
neutral and falls within the W.H.O Standard. The conductivity in both waters are high, which is an indication of ionic solute; the turbidity is high as well and does not fall
within the W.H.O standard. The average colour concentration for the surface water and dug well water are above the W.H.O limit except for the borehole water which can be accepted. The concentration of sodium conforms to the W.H.O
limits but there are slight increases in the groundwater sodium concentration which could be as a
result of the associated anions in the water and its temperature. The zinc and lead concentrations
in both waters are all above the W.H.O limit and can also be said to be as a result of its contact
with lead-containing materials and also as a result of dissolution of zinc from pipes or any other
form of contact. The iron concentrations for all groundwater fell within the WHO standard and
are acceptable, except that for surface water which is higher and can stain laundry and plumbing
fixtures.
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Via the general study and analysis, it is clearly known that the groundwater in this area as of
the time of study can only serve for agricultural and domestic use, unless been treated before it
can serve for drinking purposes (the boreholes); While the surface water, due to its colouration
and various high physical and chemical concentrations, it is best that it is not used for any
purpose.
5.1 REMMEDIATION
The following remmediation are to be made;
1. The disposal of domestic refuse should not be done indiscriminately, as unguided waste
disposal can result into the leaching of hazardous contaminants into both surface water and
groundwater during recharge, which purposely contaminant the water and makes it unfit for
human consumption and usage.
2. There should be an adequate monitoring process placed to ensure that untreated waste
effluents are not disposed in the environment.
3. As discovered via the laboratory analysis, most of the groundwater physiochemical properties
fall in accordance with the W.H.O limit and of which can be said to serve for domestic and
agricultural purposes, but also can be treated when needed for drinking purposes.
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