Evaluating the status and proposing some soltions to improve domestic water quality in xuan mai town chuong my district ha noi

VIETNAM NATIONAL UNIVERSITY OF FORESTRY STUDENT THESIS Title EVALUATING THE STATUS AND PROPOSING SOME SOLTIONS TO IMPROVE DOMESTIC WATER QUALITY IN XUAN MAI TOWN, CHUONG MY DISTRICT, H

VIETNAM NATIONAL UNIVERSITY OF FORESTRY

STUDENT THESIS

Title EVALUATING THE STATUS AND PROPOSING SOME SOLTIONS TO IMPROVE DOMESTIC WATER QUALITY IN XUAN MAI TOWN,

CHUONG MY DISTRICT, HA NOI

Major: Natural Resources Management

Code: D850101

Faculty: Forest Resources and Environmental Management

Student: Nguyen Dieu Huyen Student ID: 1453092195 Class: K59 Natural Resources Management Course: 2014 – 2018

Advanced Education Program Developed in collaboration with Colorado State University, USA

Supervisor: Assoc Prof Bui Xuan Dung

Ha Noi, 2018

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Firstly, I would like to express my great appreciation to Assoc Prof Bui Xuan Dung who is my adviser for supporting me during conducting the thesis Without his patient guidance, motivation and immense knowledge, this thesis could not be completed

Secondly, I also would like to say thanks to lecturers, who have taught us for more than 4 years and to the cooperation of Vietnam National University of Forestry and Colorado State University, especially, the faculty of Forest Resources and Environment Management

Besides, I also deeply thanks to M.Sc Bui Van Nang and Ms Nguyen Thi Ngoc Bich of the Center for Environmental Analysis and Geospatial Applications for providing

me with the measurement instruments and helping me measure the indicators to complete

my thesis

Finally, I would like to thanks to my family, my friends who always encourage, take care and help me to overcome difficulties in the life

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TABLE OF CONTENTS

ACKNOWLEDGEMENT i

TABLE OF CONTENTS ii

LIST OF ABBREVIATIONS i

LIST OF TABLES iii

ABSTRACT 1

I INTRODUCTION 2

1.1 Introduction 2

1.2 Literature review 4

1.2.1 Some indicators used to evaluate the quality of domestic water 4

1.2.2 Effects of some indicators in domestic water on human health 5

1.2.3 Some research about the domestic water in the world and Vietnam 9

II GOALS AND SPECIFIC OBJECTIVES 11

2.1 Goals 11

2.2 Specific objectives 11

III STUDY SITE AND METHODS 12

3.1 Selection of research site 12

3.1.1 Natural conditions 13

3.1.2 Social-economic conditions 14

3.2 Methods 15

3.2.1 Investigating the situation of domestic water use of households 15

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3.2.3 Laboratory sample processing 21

3.2.4 Comparative assessment method 21

3.2.5 Building up the level distribution map for water quality 22

IV RESULTS & DISCUSSION 25

4.1 The situation of domestic water use of households in Xuan Mai town 25

4.1.1 The type of domestic water use in Xuan Mai town 25

4.1.2 The type of water treatment equipment in Xuan Mai town 27

4.1.3 The water supply situation in Xuan Mai town 28

4.1.4 Demand for tap water 28

4.2 Evaluating the domestic water quality in Xuan Mai town 29

4.2.1 Evaluating the domestic water quality through questionnaires 29

4.2.2 Evaluating the domestic water quality through indicators analysis 31

4.2.3 Causes of domestic water pollution in Xuan Mai through interview 39

4.2.4 Spatial distribution map of water quality level in Xuan Mai 40

4.3 Proposing some solution to improve the domestic water quality in Xuan Mai 42

4.3.1 Technology solutions 42

4.3.2 Solutions for water management 43

4.3.3 Solutions to raise awareness of local people 44

V CONCLUSION AND RECOMMENDATIONS 45

5.1 Conclusion 45

iv

5.3 Recommendations 46 REFERENCES 47 APPENDIX 49

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UNESCO United Nations Educational, Scientific and Cultural Organization

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LIST OF FIGURES

Figure 3.1 Map of study site 12

Figure 3.2 Investigating locations for the interview in study site 16

Figure 3.3 Sampling location in study site 17

Figure 3.4 Methodology flowchart 24

Figure 3.5 IDW methods for each parameter 24

Figure 4.1 The type of domestic water use in Xuan Mai town 25

Figure 4.2 Some measures used to treat water resources in Xuan Mai town 27

Figure 4.3 Evaluating of households in 9 hamlets about domestic water quality 29

Figure 4.4 The amount of pH in water samples compared to standards 32

Figure 4.5 The amount of TDS in water samples compared to standards 33

Figure 4.6 The amount of turbidity in water samples compared to standards 34

Figure 4.7 The amount of hardness in water samples compared to standards 35

Figure 4.8 The amount of Chloride in water samples compared to standards 36

Figure 4.9 The amount of Fe in water samples compared to standards 37

Figure 4.10 The amount of Mn in water samples compared to standards 38

Figure 4.11 The amount of N-NH4 in water samples compared to standards 39

Figure 4.12 Domestic water quality map in Xuan Mai 40

Figure 4.13 The results about domestic water quality between two methods 41

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LIST OF TABLES

Table 3.1 Location of sampling sites in Xuan Mai town 17

Table 3.2 Analysis methods of water quality indicators in laboratory 21

Table 3.3 Limits of water quality indicators 22

Table 3.4 Ranking and classification of water quality zones 24

Table 4.1 The assessment of local people about of domestic water 28

Table 4.2 Demand of using tap water in Xuan Mai town 28

Table 4.3 Evaluate the percentage of households about domestic water quality 30

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ABSTRACT

Xuan Mai is a small town in the west of Hanoi The population is quite crowded and the economy is increasing fast Along with this development, the demand for clean water of local people is also going up However, the quality of domestic water in the village has not been properly concerned To assess the water quality, the thesis used various research methods such as semi-structured interview with questionnaires, stratified sampling method, data processing and assessment of the domestic water quality in the town by examining some indicators like pH, TDS, hardness, turbidity, chloride, Fe, Mn, N-NH4+ In addition, the project has used ArcMap software to build up the level distribution map to water quality in Xuan Mai The research results has compared with QCVN 01:2009/BYT, QCVN 02:2009/BYT and WHO, 2017 that express some indicators

in water samples exceed the allowable limit In which, 16 samples with the contents of iron exceed allowed value of QCVN 02:2009/BYT, 12 samples with manganese contents are higher than the allowable value for drinking water There are some water samples that are taken next market, next agricultural area and river that having many wastes water, pesticides and flood However, this water sources haven’t not harmed to the local people’s health yet Business, increasing number of people in the town and bad awareness of people are major socio-economic development activities that contribute to the degradation

of Xuan Mai domestic water quality To contribute to improve the quality of domestic water, the thesis proposes some solutions such as: using high-technology machine, applying some new policies for water management, raising awareness of local people about the importance of domestic water quality

In addition, domestic water sources are highly variable in terms of quality and quantity and depending on the situation, the sources include a stream, a spring, a hand-dug well, a borehole with hand-pump, a rainwater collection system, a piped water supply with tap or house connection, or water vendors (U.S Prasad & Indranil De, 2016) In the United States, having approximately two-thirds of the population consumes domestic water from surface water sources And approximately one-third of the population drinks water from groundwater sources (EPA, 2017) Besides, according to the 2011 Census of India, more than half of rural households depend upon hand pumps as their main source of drinking water (U.S Prasad & Indranil De, 2016) In many countries in the world, groundwater is considered to be the main source of drinking water, including Vietnam (according to the General Department of Environment, groundwater accounts for about 35% to 40% of the total domestic water supply) Moreover, tap water (mainly in urban) and rainwater (mainly

in rural) are also commonly used in Vietnam (Chi, 2018)

The same as domestic water sources, the demand for domestic water use in countries are also different According to UNEP, domestic water consumption in

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developed countries (500-800 liters per person per day) is about six times greater than in developing countries (60-150 liters per person per day) (UNESCO,1999) In the world, about 70% of all available freshwater is used for agriculture, only 8% is used by domestic

In the low and middle income countries, domestic water use also accounts for 8% (UNEs, 2003) In Vietnam, the standard of domestic water supply for urban population is low (40-

50 liters/person/day), while in rural areas, where 75% of the population live in the country, only 44% of the population has access to clean domestic water The rest must use water sources of ponds, lakes do not ensure clean (Huong, 2014)

The quality of domestic water sources doesn’t guarantee hygiene that can lead to some common diseases for the human such as diarrhea, typhoid, hepatitis A, kidney damage, diphtheria and skin lesions According to the statistic of WHO, 80% of the disease

in developing countries is related to water sources and the environment According to statistics from the Ministry of Health, each year Vietnam has about 150,000 new cancer patients and over 75,000 deaths from cancer In particular, water pollution is identified as one of the major causes that are closely related to this situation (N T M Xuan, 2017) Because water plays an important role in body human health Approximately, an adult body is made of two-thirds of water that up to 75% of the total body weight The amount

of water varies, depending on the organ Much of the water is in blood plasma (20% of the body's total) According to a study performed by H.H Mitchell, published in the Journal of Biological Chemistry, the amount of water in the human heart and brain is 73%, the lungs are 83%, muscles and kidneys are 79%, the skin is 64%, and the bones are around 31% (Helmenstine, September 28th,2018)

From the above data, we need to control water quality The more and more urgent

in the condition that the water source is increasingly polluted due to impacts from industrial parks, waste from agricultural production and daily life waste of people have not

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been paid attention and treatment It is important to emphasize the solution of drinking water from residential areas that are not properly paid attention Therefore, it is necessary

to reach out to households in search of solutions to improve domestic water quality

Xuan Mai town is one of the five satellites urban in Hanoi It is a center of many universities and companies with the process of modernization and industrialization With that, the population here is also growing rapidly From these, the demand of local people for domestic water is very large This is the pressure on the system of socio-economic development Domestic water supply resource is various in the area, but mostly groundwater In the process of formation and development, the local people still use groundwater for drinking and production However, due to the long exploitation period and the risk of pollution from domestic sewage, the quality of groundwater in some place can

be polluted, because of the increased concentrations of some environmental parameters, or the appearance of the substance Therefore, we need more specialized research to improve water quality and solutions to ensure clean water for the people in Xuan Mai

From the above issues, I choose the topic "Evaluating the status and proposing some solutions to improve domestic water quality in Xuan Mai town, Chuong My district, Hanoi" It is necessary to embrace the current water quality in order to have

appropriate treatment measures to ensure the quality of water for daily life as well as

protect the health of people

- Iron and manganese are used to assess the level of groundwater contamination due

to heavy metals and the level of pollution of these indicators in groundwater due to wastewater from industrial and agricultural areas and landfills

- Salinity and chloride can be used to assess the level of contamination due to industrial wastewater or domestic wastewater

c Biological indicators

Bacterial indicators such as coliforms to assess the level of waterborne pathogens, the total number of anaerobic bacteria that assess the level of contamination of organic matters of domestic waste And the total number of bacteria aerobic capacity assessment of organic matter in water sources

1.2.2 Effects of some indicators in domestic water on human health

a pH

PH is one of the most important factors in determining the chemical properties of water pH is an important indicator for each stage of the environment, which is an indicator that need be tested on water quality If pH <7, water often contains many acid-base ions, it can corrode metal with pipes and water containers, which indirectly affect human health If you regularly use water with high pH (pH > 8.5), it is easy to get diseases related to kidney stones, gallstones

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According to the World Health Organization, Drinking water with an elevated pH above 11 can cause skin, eye and mucous membrane irritation On the opposite end of the scale, pH values below 4 also cause irritation due to the corrosive effects of low pH levels (Rogers, October,3rd, 2017)

b Hardness

Water hardness in most groundwater is naturally occurring from weathering of limestone, sedimentary rock, and calcium-bearing minerals Hardness is a property of water that is not a health concern, but it can be a nuisance Hard water can cause mineral buildup in plumbing, fixtures, and water heaters, and poor performance of soaps and detergents For human health, hardness water is the cause of kidney stones and one of the causes of arterial occlusion due to calcification in the inner wall of the artery (USGS, 15-Dec-2016)

c TDS

TDS is often taken as the basis for determining the level of clean water and represents the total concentration of dissolved substances in water TDS is made up of inorganic salts such as calcium, magnesium, potassium and sodium, as well as a small amount of organic matter such as carbonates, nitrates, bicarbonates, chlorides and sulfates TDS can be a necessary micronutrient element for the human body But if the TDS level is high, it can produce hard water, which leaves deposits and films on fixtures, and on the insides of hot water pipes and some consequences for human health like hardness (P G

Mr Brian Oram, 2014)

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d Turbidity

Turbidity indicates the concentration of suspended solids in water (colloidal, clay, algae, microorganisms, etc) Water turbidity causes discomfort to the user and normally turbid water is often accompanied by microorganisms

Excessive turbidity in drinking water may also represent a health concern Turbidity can provide food and shelter for pathogens If not removed, turbidity can promote regrowth

of pathogens in the distribution system, leading to waterborne disease outbreaks, which have caused significant cases of gastroenteritis (USGS, 02-Dec-2016)

e Fe

In groundwater, iron usually exist with iron 2 form (Fe2+) which causes the water to have a very unpleasant smell When exposed to air, Fe2+ will be converted to Fe3+precipitated red-brown that cause loss aesthetic of water, making clothes stained yellow, floors, stained equipment sepia Moreover, when the water flows through the pipe, iron deposits will cause rust, clogging in the pipe In addition, the amount of iron in the water will make food deteriorate, change the color, taste; reduces the digestion and absorption of foods, causing indigestion

Iron is a necessary element for the human body Iron is not considered to be harmful

to human health at moderate levels In contrast, excess body iron in excess of 0.3 mg / l also causes iron deposition in tissues such as the heart, liver, endocrine glands leading to severe dysfunction of these organs (Le Van Nhan, July 22nd, 2016)

f Manganese

Manganese is present in water in the form of dissolved ion (Mn2+) If the content is less than 0.1 mg / l, manganese is good for health However, if the content of manganese is 1-5 mg / l, it will affect some organs of the body Mn absorption into the body can be toxic

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to the lungs, nervous system, kidneys and heart Long-term exposure to manganese can reduce language ability, memory loss, reduced mobility associated with hand movement and eye movement Long-term poisoning leads to abnormal nerves such as gait and abnormal language

Manganese is particularly harmful to children because the child's body easily absorbs

a lot of manganese while the discharge is very little This leads to the accumulation of Mn

in the child's body, causing serious consequences (T T Xuan, Dec-25-2015)

g Ammonium

Water has high ammonium content, indicates that water has been contaminated with organic substances of nitrogen origin (wastewater, fertilizers, animal waste, etc.) Ammonium is not too toxic to the body, but if it exists in water with a content that exceeds the permitted standard, it can be transformed into carcinogens Ammonium in groundwater when it is exposed to oxygen in the air transforms into nitrate and nitrite (Canter, 1996) Nitrate and Nitrite, which affect the body, cause methemoglobin (oxygen deficiency in the blood), especially when combined with amino acids in the body to form nitrosamines that cause cancer (P Mr Brian Oram, 2014)

h Chloride

Chloride is the major ion in natural water representing salinity It is most abundant in seawater and salt mines In freshwater and in groundwater, the content of Cl- usually ranges from 20 mg / L to 800 mg / L Chloride is very useful for the body, but at high levels can cause kidney failure, contributing to increased risk of high blood pressure (World Health Organization, 2003)

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1.2.3 Some research about the domestic water in the world and Vietnam

As of today, there have been man projects, research works about water activities by scientists and student in the world and in Vietnam Some case studies are as follows:

a In the world:

“Assessment of domestic water quality: case study, Beirut, Lebanon” of Samira Ibrahim Korfali, Mey Jurdi (2007) The objective of this study is to investigate domestic water quality variation in Beirut City emerging from the chemical and microbial contamination of drinking water Results showed deterioration pattern in domestic water quality

“Microbiological and physico-chemical assessment of the quality of domestic water sources in selected rural communities of the Eastern Cape Province, South Africa” of Zamxaka M, Pironcheva G and Muyima NYO from Environmental and Natural Products Biotechnology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare (2004) This research was carried out with the purpose to determine the present micro-biological and physico-chemical qualities of domestic water sources used by Gaga, Gqumashe, and Gogogo rural communities The result was compared with the South African Standards for Domestic water quality (DWAF, 1996)

“Drinking water quality assessment” of Arvai J, Gautam B, Sapkota N from Central Department of Environment Science, Tribhuvan University, Kirtipur, Kathmandu, Nepal (2012) This study was carried out to assess the quality of drinking water from different natural resources, reservoirs and collection taps at Arthunge VDC of Myagdi district The result was compared with national and WHO guidelines

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b In Vietnam

“Research some factors about domestic water quality and some related diseases in 6 communes at Dong Hung, Thai Binh Evaluating the efficiency of some used measures” of Ngo Thi Nhu from the Military Medical Academy The project determines the number of arsenic contamination in domestic water to contribute to improving people’s health and environment sanitation The results show that 31,6% of drilling wells and 7,2% of digging wells reach the standard of hygiene in the study area

“Assessing and proposing some measures to improve the quality of domestic water

in Xuan Mai town, Chuong My district, Hanoi” of Nguyen Van Son from Vietnam National University of Forestry (2009) The research has analyzed and assessed the current status of water quality of the study area at the time of research through some indicators, and also used the WQI method to assess the water quality in Xuan Mai town The analysis results show that the water quality of the area is moderate

“Assessing the status and the demand for domestic water use of people in the area

of Xuan Mai town, Chuong My district, Hanoi” of Hoang T.T Mai, Vu T.T Phuong, Ngo Van Luc from Vietnam National University of Forestry (2010) The research results also show the current status of water sources, the demand for domestic water use of people in the town At the same time, the research also recommends some solutions to improve the efficiency of water resource use in the study area at the time of the study

“Study and propose some solutions to improve the quality of underground water sources in Tan Xuan hamlet, Xuan Mai town, Chuong My district, Ha Noi” of Nguyen Thi Thuy from Vietnam National University of Forestry (2014) The research has conducted an analysis of 30 samples with 8 indicators and compared result with QCVN 09: 2008/BTNMT Moreover, the research has also applied ArcGIS software to build up the distribution map for clean water level in Tan Xuan The results show that the quality of

II GOALS AND SPECIFIC OBJECTIVES

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III STUDY SITE AND METHODS

3.1 Selection of research site

Figure 3.1 Map of study site

Xuan Mai Town belongs to Chuong My District, Hanoi With coordinates 28°58’ north latitude, 105°05' east longitude Xuan Mai town is located on the intersection

between National Highway 6A and National Highway 21A, 33km west of Hanoi Xuan

Mai town is located:

- In the north, it borders on Dong Yen Commune, Quoc Oai District, Hanoi City

- In the south and east, it borders on Thuy Xuan Tien commune, Chuong My

district, Hanoi city

- In the west, Hoa Son commune, Luong Son district, Hoa Binh province

breeding farms and fruit trees

- The dry season starts from November to March of the following year

Annual average rainfall is 1839 mm, rainfall mainly from May to 10, the remaining months of the year rainfall are negligible The average temperature is 23.1 ° C The hottest month is 3.5 ° C (June & July) The coldest month is 8.5 ° C (January)

The humidity is relatively high and fairly uniform between months of the year Average annual humidity is 84.25% The popular wind direction is the northeast monsoon and the southeast monsoon South-east monsoon blows from November to March next year, north-east monsoon blows from April to July

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d Natural resources

- Soil : The total area of the natural land of the town is 1051.88 hectares, mainly

land brown feralit There is also alluvial soil that is filled up by two rivers Bui and Tich River, accounting for 5% of the total area of 52.59 ha, distributed in the fields in the southeast of Xuan Mai town

- Water resource: Surface water used for daily life and production depend on the

water of Bui River and Tich River through the district's pumping stations Ground water level is from 5-7m, water quality is quite good The water source is plentiful enough to meet the demand for people However, due to natural conditions and terrain distribution of

rainfall, some places will occur inundation phenomenon

3.1.2 Social-economic conditions

a Social conditions

According to the statistical report in 2017, the town has 26,512 people distributed in

9 hamlets: Tan Xuan, Tien Truong, Xuan Ha, Tan Binh, Xuan Mai, Bui Xa, Chien Thang, Dong Vai, and Tan Mai

Xuan Mai town has a large, densely populated area with a large number of workers, students and students coming from other places to universities, colleges and enterprises more and more increase yearly Xuan Mai has many schools and enterprises: Vietnam National University of Forestry, The North Vietnam College of Agriculture and Rural Development, many elementary schools, secondary schools Xuan Mai and Xuan Mai

animal feed processing factory So the population is growing rapidly

b Economic conditions

In recent years, the economy of Xuan Mai town has made remarkable progress, high growth rate, people's life improved and improved Agricultural production has achieved

3.2.1 Investigating the situation of domestic water use of households

To investigate the situation of domestic water use in the study area, the research have chosen semi-structured interview with a set of questions about the need for using water quality, the characteristics and effects of water, methods of filtering and proposing ideas for improving water quality (Appendix 1)

The research collected data throughout the area of the town of Xuan Mai, but due to overcrowding population, cost and time limit, the study could not interview all the households The research has chosen stratified sampling methods, dividing the study area into nine strata according to administrative boundaries Then from each strata, conduct a simple random survey of 10 households From that, the result within strata has lower standard deviation and smaller error in estimation than other methods

The project interviewed 90 households in 9 hamlets: Tan Xuan, Tien Truong, Xuan

Ha, Tan Binh, Xuan Mai, Bui Xa, Chien Thang, Dong Vai, and Tan Mai The purpose of this interview was to identify initially the main water resource used most in the region and have correctly identified the people’s awareness about the importance of using clean water Therefore, investigating the amount of domestic water in the whole town and the demand

of local people for using clean water

Schedule for interview: 14th 8, 2018 to 16th 8, 2018 (After the flood period)

There are total 27 samples that are collected from 9 hamlets In which, 14 samples are taken by drilling well and 13 digging well samples

Time: 14th 8, 2018 (after the flood period)

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Figure 3.3 Sampling location in study site

Sampling location are described in table:

Table 3.1 Location of sampling sites in Xuan Mai town

ID Symbol

Sample

Household owners

Water sources

Location Latitude Longitude

Van Kien

Digging well

No 18, civil group 1, Bui xa hamlet

20,902401 105,596724

Van Tuan

Digging well

No 24, civil group 2, Bui Xa hamlet

20,901212 105,595847

Van Qua

Digging well

No 13, civil group 4, Bui Xa hamlet

20,900452 105,594620

Lap

Digging well

No 26, civil group 2, Tien Truong hamlet

20,907716 105,592194

Hung

Digging well

No 33, civil group 3, Tien Truong hamlet

20,908110 105,591691

Dong

Digging well

No 22, civil group 3, Tien Truong hamlet

20,906872 105,592777

7 S07 Nguyen Digging Civil group 3, Dong 20,900607 105,592832

Civil group 4, Dong Vai hamlet

20,895096 105,579945

Van Thuan

Digging well

Civil group 4, Dong Vai hamlet

20,896203 105,582178

10 S10 Dang Van

Thang

Drilling well

No 86, civil group 5, Xuan Ha hamlet

20,902159 105,578360

Tri Cuong

Drilling well

No 5, civil group 4, Xuan Ha hamlet

20,902442 105,578858

12 S12 Tran Duc

Hanh

Drilling well

No 83, civil group 2, Xuan Ha hamlet

20,897375 105,582808

Tri Quyet

Drilling well

No 97, civil group 5, Tan Xuan hamlet

20,906565 105,574286

Thi Mo

Drilling well

No 36, civil group 6, Tan Xuan hamlet

20,904948 105,567799

Quynh

Drilling well

No 52A, civil group

4, Tan Binh hamlet

20,901526 105,574603

17 S17 Dao Van

Chin

Drilling well

No 27, civil group 4, Tan Binh hamlet

20,899752 105,572867

Thi Le

Digging well

No 54, civil group 3, Tan Binh hamlet

20,900074 105,571253

Duc Tien

Drilling well

Civil group 4, Chien Thang hamlet

20,896570 105,567114

Duc Toan

Digging well

Civil group 5, Chien Thang hamlet

20,892233 105,565891

21 S21 Phi Dinh

Thanh

Digging well

No 28, Civil group 4, Chien Thang hamlet

20,888164 105,566737

Thanh Binh

Drilling well

No 97, civil group 3, Tan Mai hamlet

20,883893 105,557614

23 S23 Luong Thi Drilling No 26, Civil group 3, 20,884330 105,559774

No 38, civil Group 2, Tan Mai hamlet

20,884787 105,561450

Chi Thanh

Digging well

No 14, civil group 2, Xuan Mai hamlet

20,906221 105,590986

26 S26 Ngo Gia

Kham

Drilling well

No 5, civil group 4, Xuan Mai hamlet

20,906810 105,588971

An

Drilling well

Civil group 5, Xuan Mai hamlet

20,905922 105,586018

b Sampling procedure

To evaluate the domestic water quality in Xuan Mai town base on the nature and characteristics of the water as well as the characteristics of natural condition and characteristics of social- economic development in the region should be selected indicators

to analyze water samples are: pH, total dissolved solids, turbidity, hardness, iron, ammonium, chloride, manganese These indicators are one of the most significant ones

assessing the hazardous or safe of water quality for users Each indicator has the specific meaning However, the heavy metals (iron, manganese…), ammonium, chloride, pH, hardness are the indicators affecting directly to the human health That is the reason why these indicators choose instead of others Water samples were taken directly from the wells

or from the point extraction

Sampling methods according to the following Vietnam standards:

- TCVN 6663-1:2011: Water quality - Sampling - Part 1: Guidance on the design

of sampling programmes and sampling techniques

- TCVN 6663-3:2008: Water quality - Sampling - Part 3: Guidance on the preservation and handling of water samples

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 Tools:

- Two plastic bottles 500ml

- Styrofoam bucket and ice for preservation of samples after collection

- Paper sticker, pen and other necessary tools

- Step 3: Over the full sample record information such as symbol samples, sampling locations, sampling days, the weather characteristics of the sampling days

- Step 4: After that, the samples were packed into Styrofoam bucket and transported

to the laboratory to analyze samples

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 Sample preservation and transportation:

Before transport, the specimen must be safe in specialized equipment, avoiding contamination Transportation does not affect the sample

After sampling, the samples should be stored at 4 ° C and kept away from direct sunlight during analysis Particularly for iron & manganese, we need to preserve samples with acid HNO3 All samples should be moved to the laboratory for analysis

3.2.3 Laboratory sample processing

Table 3.2 Analysis methods of water quality indicators in laboratory

Water quality

indicators

3.2.4 Comparative assessment method

After analyzing the indicators, the results are compared with:

- QCVN 01: 2009/BYT- National Technical Regulation on drinking water quality

- QCVN 02: 2009/BYT- National Technical Regulation on domestic water quality

- WHO, 2017- Guidelines for drinking water quality

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Table 3.3 Limits of water quality indicators

QCVN01:2009/BYT QCVN02:2009/BYT WHO,2017

3.2.5 Building up the level distribution map for water quality

In order to carry out this map, I collect the coordinates (lat/long) of the locations of the ancillary data, with the help of Global Positioning System (GPS) pertaining to the water quality parameters The further step is to digitized groundwater ancillary data using the MS Excel and assigning of GPS locations to each point which was otherwise without locations for the creation of the database Then the non-spatial data and spatial data are joined in the ArcMap 10.3 software Later on the other analysis is carried out using the IDW (Inverse Distance Weighted) Interpolation in GIS environment Interpolation makes predictions from sample measurements for all locations in a raster dataset whether or not a measurement has been taken at the location IDW is a method of interpolation that estimates cell values by averaging the values of sample data points

in the neighborhood of each parameter (Fig 3.5a-h)

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After that, a water quality map is created following the classification is shown in Table 3.4 The construction of the domestic water quality map is carried out through the overlaying of the all parameter maps The overall methodology adopted is shown in Fig 3.4 below: