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Ground Water Development and Economic Aspects in China
573
IN CHINA
GROUND WATER DEVELOPMENT AND ECONOMIC ASPECTS
Li Lierong, Bureau of Hydrogeology and Engineering Geology, 20 Dahuisi, H a dian District, Beijing, China Yang Qilong, China Geo-Engineering Corporation, 20 Dahuisi, Haidian District, Be jing, China ABSTRACT
This paper provides the Latest information concerning the developaent, utilization and economic aspects of groundwater in China. The drilling costs for one meter of cased well in different formation, with varied depth and diameters, China-made drilling rigs and drilling methods are given. Some drilling projects of cased wells in Africa and Asia countries are presented. 1 INTRODUCTION
China
is
mid
a
surface
important
water as a source of water supply,
role in
development
of people’s Life. In of groundwater, have
got
a
reducing
has played
of national economy
the course of the development
the exploitation departments
great deal of department
has
and upgrading
in different regions regard
also put
forward
series
of
guiding
on putting groundwater to rational exploitation. have promoted the progress in groundwater utilization. four
is
sure
modernizat ion
inctirding
and
with
the
construct ion,
groiindwater,
development
the need
will increase
of
water
with each
we
economic
should
aake
prinriples
f o t tow
of
These the
resources,
passing
day.
t e c h o tog i caL economic environaental benefits in the utilization of groundwater.
Therefore, and
that
to
and raising economic benefit. The
policies
It
an
of utilization
successful experience with
water extraction costs
government
in the developaent Goundwater, which coabines
with a Long history
i tization of groundwater,
tit
with
country
and
to
raise
the
the
social,
AND UTILIZATION OF GROUNDWATER IN CHINA With the development of industry and agriculture, the
2 DEVELOPMENT
of
urban
requirement
area of
and
upgrading of
the
living
expansion
standards,
water has been increasing day by day.
the
Continuous
674
aridity
the
in
pollution
of
last years has resulted in serious
surface
water
and worsening
Therefnre, the exploitation and utilization
of
of
shortage
water
and
quality.
groundwater should
b e integrated closely. China has vast expansion of territory and its natural conditions vary
from
one
place to another. Different regions differ greatly
in climate, Landform, plant, river system and gological As far as
distribution
roughly be divided into
of groundwater is concerned, two
parts
by
Qinling
strurture. China
mountains
could which
traverses from east to west.
In North China, the main plain
Quternary sand
formations-
and
Because of
graveL
has
a
shortage of
now, groundwater exploitation
and
series
surface
of
water
bearing
wator in this region
consumption are increasing year
by year. At present, in a lot of big and medium cities in North China, such as Beij ing, Shij iazhuang, groundwater became the main source of water supply. In other groundwater combined with surfaco water
serves
for the source of water supply. Pumping and
use
of
groundwater is inrreasing in the South. In the southern China,where
the hilts and mountains are the most of Landforas, the exploitation of groundwater
from
precipitation
is
bedrocks is increased now. Because the yearly
very
uneven,
more
over,
surface
water
is
contaminated in local places. According to
incomplete data
in recent years
the total ground
water withdrawal in China is about 760x10' m'/yr. Among than water of 600X10' m'/yr
is got by pumpage from exploited regions. Others
are from
springs and underground rivers. The yield in plain
regions
large is
about
580x10'
m'lyr.,
i t makes
up
76%
of
total
withdrawal of groundwater in China. In mountainous region, the yield is 180x10' m'/yr.,
which makes up 24% of the total.
The yield of
groundwater of seventeen North provinces is about 66OXlOh'/yr.It makes up 87% of the total yeild of groundwater in our country, and is about 42%
of
provinces. For rational
the recoverable reserves of groundwater of thosr
and
econoaic
exploi tation
of
groundwater,
hydrogeological teams have been carrying out syslenatical explora tion and mapping to find out hydrogrological conditions in different areas. Up to now, except Qinhai-Tibet
plateau
and
some
difficult
575
high mountains, deserts, forests, hydrogeological
regions, such as
mapping of scale 1/200000-1,500000 has covered an area of 6,600,000
km’ (two thirds of whole country’s inland territory). In plain areas, mapping of scale 1 50000 1 100000 has covered an area of 69,000 km’ ( o n e tenth of the whole). This work is very useful for rural rsater s u p p I y
and
agricultural irrigation.
In itrban
detailed esptoratioris have been carried out. On the
arcas, more
basis of these
investigation ” The Atlas of Hydrogeological Maps of the People’s Republic of China” was published in 1979, which summaries the main results of regional hydrogeologicat investigation in China. In 1981-1985, assessment of groundwater resources of the whole country had h e r n done. The resources of pore water, fissure water and karst water were calculated a s following
TABLE
1 Natural resources o f groundwater in China
Are as
I Types of yroundwater 1
Plains
Fissure water
Super imposed Total
I I
Pore water in valleys and basins Total
Natural resouces
4250.81 2034. 26
Karst water
areas
x 10m’/,yr.>
2503.90
Porc viatrr
Mom t a i n
(
I
I
458.72 6743.79 530.86 8716.84
576
TABLE 2
Capital costs of drilling and irrigation and piimp costs US$ >
depth Dr.i1 1 i ng
Equipment
I Total
10--50
< vacuum 268 1 300-
400
I
400500
I
3485
536
3217
Rates of one well < a’/hr > 3 -5
0.2 -0.3
80
10-20
1.3-1.5
100
150-200
10-13
24 1
150-200
I I
In plains,
location of
ancient river courses, houdary of Tatty
and fresh groundwater, depth of water bearing formation are determined by geophysical methods. In Hebei province, each county has g o t its own small geophysical group. In mountainous regions, the geologic structures and rock fractures are very complicated, s o geophysical methods would
be key factor to determine the propel welt field. Some cheap but efficient geophysical instruments made by Local factories are applied widely. Reduction of drywell, enlargement
of
yield
in well, Lower
the
total
expenses
for
drilling and pumping. In areas, where water is buried deeply and quite difficult to pump, the costs of irrigation could be higher than the income of Local people. Therefore the development and utilization of groundwater have been rather Limited in these areas. Overexploitation of groundwater is another serious problem results in the water on development of ground water, which depression in area, land subsidence, ground collapse, deterioration of water quality and so on. Since some departments pay tittle attention to waste disposal, i n many arras, groundwater, even deep ground water is polluted t o various ex tent. 3 ECONOMIC ASPECTS OF GROUNDWATER IN CHINA
In China, groundwater abstraction is realized mainly by manual
577 or
machines to dig the Large-diameter wells
mechanica
we Is
radiation The
wells.
Large-diameter
wells
are
generally
dug
by
the
experienced peasants. Casedwells are mainly constructed by the professional hydrogeologicat units or the water conservancy departments.
Different
rigs and
adopted according to the
construction methods
have
been
different depth, diameter and formation.
After many years exploitation the capital costs of drilling and are rather clear.Drilling costs per one meter of cased
irrigation wells
by
rigs,made in China are shown in Table 3.
Types of rigs
Expense i tems
DDP-100
SPC-300, SPJ-300H
SOY-600
Personnel Mat er i a Ls Amor t iza t ion Pipe amor t iza--
5.1 9.4 0.66 0. 28
8.52 13.10 2.08 2.61
12.89 16.91 1-00 6. 25
Rep 21 i r i ng Tr a m p o r t
2. 20 2.32 3.98
2. 17 2.63 6.31
2.96 4.88 9-00
t ion
Management
I
Total
23.94
I
37.42
I
53.89
Explanation for Tahle 3, 1. ALL drilling costs E, are made for rock category V
750m
for
is For other rock categories, w e l l diameters, well depth i t necessary to calculate the other drilling costs E, through E, using special coefficients-
E =
f , . f, . f, . Eo E, - Drilling costs for special well. Rock category coefficient, f, . f, f, . ~
depth coefficient and diameter coefficient, respect ivo Ly. < see Tab Le 4, 5,6) Rock category coefficient
578
TABLE 4
coe f f i c i e n t s
Rock
I
forma t ion
soil
fr
I
~
Artificial s o i l , sand
0. 18
0. 26
I
VT
I
VII
I
VIII
Pebble, silicified dolomite
Bou Lderpebb Le, granite
1. 25
1.67
2.86
400
fd
100--200 1. 0 9
1
9 3,‘4 inch 1.45
With
downhole
1
ma
1-40
I
compressor.
mountain
areas
SPC 300 r i g the c o e f f i c i e n t is
1 2.15
coefficierit----0.25
for
>
efficiency---dwhr.
the
though
lot,
Example,
.
Drill
g r a v e l , rlia.300 mm, conventional t o t a l expense
In
f,
case
of
and a t same time r o c k c a t e g o r y
categories
all
-
to
all
more
than V
above
wet
20-100
m
method
adjustment
the
case is
Eo
f,
water
drilling is,
.
the cost
a d j u s t i n g t o i n c r e a s e o f equipment and
According
f,
rock
d r i [ l i n g c o s t i s reduced,
expense f o r d r i l l i n g one meter f o r m a t i o n in p a r t i c u l a r f,
I
f u e l and h i g h
Lacking of water.
corisidered t o be 5.0,
E =
I
350--450
hammer d r i l l i n g method i n h a r d r o c k s < t h e
So, g e n e r a l ty speaking, in
1.53
I 1-89
1.89
500 ---600
400--500
method cortsumes t o o much o i l
hmer
particularly fuel (f,)
280-350
5.88
the e f f i i , i r n r y i s i n c r e a s e d q u i t e a
ulpgory)
downliole
300--400
I
Strong silicoLites
1.29
I
X
I
4.0
1-19
1.0
I
IX Boulder, silica-Lites
200---300
pebble gravel limestorit-
0.67
0.53
Grave 1pehb le, dotomi te, basalt
Deli t h (m)
i
s a n d g r a v e l Semi-consotis a n d s t o n e d a t e d sandgravel p e t i t e
w i t h d e p t h of 1000 C0-20m s
g r a n i t e , d i a . 3/4”
< r o t a r y method
>-
is
sand
Using t h e
with r o r e b i t s ) the
579
B = 0 . 5 3 X 1 X 1 . 8 9 x 3 7 . 4 2 ~2 0 + 2 . 8 6 X 1 X 1 . 4 5 X 3 7 . 4 2 X 8 0 C m ) = 131.64 Comprehensive cost for one meter CEO
)
is 1 3 1 . 6 4 US$ expenses is,
Using the downhole hammer drilling method the total
B =
0 . 5 3 X l x 1 . 8 9 X 3 7 . 4 2 X 204- 0. 25 :K 1 X 1.45:<37.42'.<5.
O X 80
= 749.67 + 5425-90 = 61.76 Comprehensive cost for one meter CE,) is 6 1 . 7 6 US$ Comprehensive
hydrogeological
work c o s t s per one
month
are
shown in Table 7
Geology investigation
I tens
in field
I
1. Personne 1 2. Mat er i a1 3 Amor t i zation 4.Repairing 5 . Transport 6.Other direct expenses 7. Manngement
I
Water analyses
distur -bu ted sample
in office I
0.04
Total
soil engineering analyses imdisturbu tcd sample
I
2.0
0.04
0.2
long-term observat ion work
6.0
61.7 11.8
6.4 13.4 15.5
6.4 4.3 15.5
0.02 0.01 0.01
0.1 0.1 0.4
0.4 0.3 1.3
10- 7 25. 2 10.7
27.9
23.6
0.05
0.0
2.4
32.7
0.26
4.0
112.0
138.8 1 1 1 3 . 9
I
I
163.5
China Geo-Engineering Corporation, whose previous name is China
Geo-Exploration
Corporation, has
been
Water
well
is a large professional state-owned enterprise
supply
cowltries Somalia,
Engineering
registered as economical and legal entity.
years, CGC has constructed about 1 0 0 water
thirty water
and
of
and Asia,
Africa
and Latin
America,
Mozambique, Nigeria, Bukkin,
which
the
well
in
mineral exploration projects
Sanegal,
In
past
dri 1 ing,
thirty
such
as
more Mali,
Eth op i a,
Faso,
Pakistan, Sri Lanka, Peru and so on. of 4 5 0 water and Sikasso) in Mali. 1. Drilling
It the
wells
in rural areas CFana, Kamtiata
is financod by the World Bank. The average depth is total
drilling
diameter 9 7/8-12
1/4
footage
27000m <900flm
inch,and rotary drilling
is
60m and
sediment
method;
180000
wit11 in
580
sandshale with project began
diameter 1.2 inch and downhole hammer method). Thr in November 1985. Because of high drilling
efficiency
or 2,074,011.5 US$
106-4 W S $ 2. The Construction of 485 Tubewells Projcc t
It is
The cost per one meter in South Rohri
has been financed by the Asia Bank. Average depth of
47.5m
with installation o f 8“- 12” pipes and
is
screens.
welts Total
drilling footage is 23239.301 and total price of contract
wilt be ending in two years. 3.Tlie Construction of 300 Tubewells in North and Extreme-North Provinces in Cameroon. This project is financed by the World Bank. CGC began the project in September 1987 with total drillings of 21342n arid total price of contract (including pipe) of 804,815,000 FCFA or 2,728, 186 US$. The cost per each meter i s 127,83 U S $ . &‘The Water Resource Exploration and Well Drilling in Puttatan and Chilaw towris, Sri Lanka. The project was commenced in October 10, 1985 and completed in Jime,1987. The exploratory wells of 5 3 and production welts of 21 with tube dia. o f 24.7-32.5cm were drilled-The total drilling footaye is 3048.28~. The total water ftowrate is 2895m’ld and allowable exploitative amount of underground water in both towns is 17992m’./d
Note, Karez A kind of irrigation construction in XinJian Region, Northwest Chiria. First,a.sr:ries of wells from the hit\ slope to the fields are
dug,
then, dig through in the
bottom of wells, make a
connection into the hidden channel t o draw the netted snow in mountain and underground t o irrigate the field.
the
IN CHINA
GROUND WATER DEVELOPMENT AND ECONOMIC ASPECTS
Li Lierong, Bureau of Hydrogeology and Engineering Geology, 20 Dahuisi, H a dian District, Beijing, China Yang Qilong, China Geo-Engineering Corporation, 20 Dahuisi, Haidian District, Be jing, China ABSTRACT
This paper provides the Latest information concerning the developaent, utilization and economic aspects of groundwater in China. The drilling costs for one meter of cased well in different formation, with varied depth and diameters, China-made drilling rigs and drilling methods are given. Some drilling projects of cased wells in Africa and Asia countries are presented. 1 INTRODUCTION
China
is
mid
a
surface
important
water as a source of water supply,
role in
development
of people’s Life. In of groundwater, have
got
a
reducing
has played
of national economy
the course of the development
the exploitation departments
great deal of department
has
and upgrading
in different regions regard
also put
forward
series
of
guiding
on putting groundwater to rational exploitation. have promoted the progress in groundwater utilization. four
is
sure
modernizat ion
inctirding
and
with
the
construct ion,
groiindwater,
development
the need
will increase
of
water
with each
we
economic
should
aake
prinriples
f o t tow
of
These the
resources,
passing
day.
t e c h o tog i caL economic environaental benefits in the utilization of groundwater.
Therefore, and
that
to
and raising economic benefit. The
policies
It
an
of utilization
successful experience with
water extraction costs
government
in the developaent Goundwater, which coabines
with a Long history
i tization of groundwater,
tit
with
country
and
to
raise
the
the
social,
AND UTILIZATION OF GROUNDWATER IN CHINA With the development of industry and agriculture, the
2 DEVELOPMENT
of
urban
requirement
area of
and
upgrading of
the
living
expansion
standards,
water has been increasing day by day.
the
Continuous
674
aridity
the
in
pollution
of
last years has resulted in serious
surface
water
and worsening
Therefnre, the exploitation and utilization
of
of
shortage
water
and
quality.
groundwater should
b e integrated closely. China has vast expansion of territory and its natural conditions vary
from
one
place to another. Different regions differ greatly
in climate, Landform, plant, river system and gological As far as
distribution
roughly be divided into
of groundwater is concerned, two
parts
by
Qinling
strurture. China
mountains
could which
traverses from east to west.
In North China, the main plain
Quternary sand
formations-
and
Because of
graveL
has
a
shortage of
now, groundwater exploitation
and
series
surface
of
water
bearing
wator in this region
consumption are increasing year
by year. At present, in a lot of big and medium cities in North China, such as Beij ing, Shij iazhuang, groundwater became the main source of water supply. In other groundwater combined with surfaco water
serves
for the source of water supply. Pumping and
use
of
groundwater is inrreasing in the South. In the southern China,where
the hilts and mountains are the most of Landforas, the exploitation of groundwater
from
precipitation
is
bedrocks is increased now. Because the yearly
very
uneven,
more
over,
surface
water
is
contaminated in local places. According to
incomplete data
in recent years
the total ground
water withdrawal in China is about 760x10' m'/yr. Among than water of 600X10' m'/yr
is got by pumpage from exploited regions. Others
are from
springs and underground rivers. The yield in plain
regions
large is
about
580x10'
m'lyr.,
i t makes
up
76%
of
total
withdrawal of groundwater in China. In mountainous region, the yield is 180x10' m'/yr.,
which makes up 24% of the total.
The yield of
groundwater of seventeen North provinces is about 66OXlOh'/yr.It makes up 87% of the total yeild of groundwater in our country, and is about 42%
of
provinces. For rational
the recoverable reserves of groundwater of thosr
and
econoaic
exploi tation
of
groundwater,
hydrogeological teams have been carrying out syslenatical explora tion and mapping to find out hydrogrological conditions in different areas. Up to now, except Qinhai-Tibet
plateau
and
some
difficult
575
high mountains, deserts, forests, hydrogeological
regions, such as
mapping of scale 1/200000-1,500000 has covered an area of 6,600,000
km’ (two thirds of whole country’s inland territory). In plain areas, mapping of scale 1 50000 1 100000 has covered an area of 69,000 km’ ( o n e tenth of the whole). This work is very useful for rural rsater s u p p I y
and
agricultural irrigation.
In itrban
detailed esptoratioris have been carried out. On the
arcas, more
basis of these
investigation ” The Atlas of Hydrogeological Maps of the People’s Republic of China” was published in 1979, which summaries the main results of regional hydrogeologicat investigation in China. In 1981-1985, assessment of groundwater resources of the whole country had h e r n done. The resources of pore water, fissure water and karst water were calculated a s following
TABLE
1 Natural resources o f groundwater in China
Are as
I Types of yroundwater 1
Plains
Fissure water
Super imposed Total
I I
Pore water in valleys and basins Total
Natural resouces
4250.81 2034. 26
Karst water
areas
x 10m’/,yr.>
2503.90
Porc viatrr
Mom t a i n
(
I
I
458.72 6743.79 530.86 8716.84
576
TABLE 2
Capital costs of drilling and irrigation and piimp costs US$ >
depth Dr.i1 1 i ng
Equipment
I Total
10--50
< vacuum 268 1 300-
400
I
400500
I
3485
536
3217
Rates of one well < a’/hr > 3 -5
0.2 -0.3
80
10-20
1.3-1.5
100
150-200
10-13
24 1
150-200
I I
In plains,
location of
ancient river courses, houdary of Tatty
and fresh groundwater, depth of water bearing formation are determined by geophysical methods. In Hebei province, each county has g o t its own small geophysical group. In mountainous regions, the geologic structures and rock fractures are very complicated, s o geophysical methods would
be key factor to determine the propel welt field. Some cheap but efficient geophysical instruments made by Local factories are applied widely. Reduction of drywell, enlargement
of
yield
in well, Lower
the
total
expenses
for
drilling and pumping. In areas, where water is buried deeply and quite difficult to pump, the costs of irrigation could be higher than the income of Local people. Therefore the development and utilization of groundwater have been rather Limited in these areas. Overexploitation of groundwater is another serious problem results in the water on development of ground water, which depression in area, land subsidence, ground collapse, deterioration of water quality and so on. Since some departments pay tittle attention to waste disposal, i n many arras, groundwater, even deep ground water is polluted t o various ex tent. 3 ECONOMIC ASPECTS OF GROUNDWATER IN CHINA
In China, groundwater abstraction is realized mainly by manual
577 or
machines to dig the Large-diameter wells
mechanica
we Is
radiation The
wells.
Large-diameter
wells
are
generally
dug
by
the
experienced peasants. Casedwells are mainly constructed by the professional hydrogeologicat units or the water conservancy departments.
Different
rigs and
adopted according to the
construction methods
have
been
different depth, diameter and formation.
After many years exploitation the capital costs of drilling and are rather clear.Drilling costs per one meter of cased
irrigation wells
by
rigs,made in China are shown in Table 3.
Types of rigs
Expense i tems
DDP-100
SPC-300, SPJ-300H
SOY-600
Personnel Mat er i a Ls Amor t iza t ion Pipe amor t iza--
5.1 9.4 0.66 0. 28
8.52 13.10 2.08 2.61
12.89 16.91 1-00 6. 25
Rep 21 i r i ng Tr a m p o r t
2. 20 2.32 3.98
2. 17 2.63 6.31
2.96 4.88 9-00
t ion
Management
I
Total
23.94
I
37.42
I
53.89
Explanation for Tahle 3, 1. ALL drilling costs E, are made for rock category V
750m
for
is For other rock categories, w e l l diameters, well depth i t necessary to calculate the other drilling costs E, through E, using special coefficients-
E =
f , . f, . f, . Eo E, - Drilling costs for special well. Rock category coefficient, f, . f, f, . ~
depth coefficient and diameter coefficient, respect ivo Ly. < see Tab Le 4, 5,6) Rock category coefficient
578
TABLE 4
coe f f i c i e n t s
Rock
I
forma t ion
soil
fr
I
~
Artificial s o i l , sand
0. 18
0. 26
I
VT
I
VII
I
VIII
Pebble, silicified dolomite
Bou Lderpebb Le, granite
1. 25
1.67
2.86
400
fd
100--200 1. 0 9
1
9 3,‘4 inch 1.45
With
downhole
1
ma
1-40
I
compressor.
mountain
areas
SPC 300 r i g the c o e f f i c i e n t is
1 2.15
coefficierit----0.25
for
>
efficiency---dwhr.
the
though
lot,
Example,
.
Drill
g r a v e l , rlia.300 mm, conventional t o t a l expense
In
f,
case
of
and a t same time r o c k c a t e g o r y
categories
all
-
to
all
more
than V
above
wet
20-100
m
method
adjustment
the
case is
Eo
f,
water
drilling is,
.
the cost
a d j u s t i n g t o i n c r e a s e o f equipment and
According
f,
rock
d r i [ l i n g c o s t i s reduced,
expense f o r d r i l l i n g one meter f o r m a t i o n in p a r t i c u l a r f,
I
f u e l and h i g h
Lacking of water.
corisidered t o be 5.0,
E =
I
350--450
hammer d r i l l i n g method i n h a r d r o c k s < t h e
So, g e n e r a l ty speaking, in
1.53
I 1-89
1.89
500 ---600
400--500
method cortsumes t o o much o i l
hmer
particularly fuel (f,)
280-350
5.88
the e f f i i , i r n r y i s i n c r e a s e d q u i t e a
ulpgory)
downliole
300--400
I
Strong silicoLites
1.29
I
X
I
4.0
1-19
1.0
I
IX Boulder, silica-Lites
200---300
pebble gravel limestorit-
0.67
0.53
Grave 1pehb le, dotomi te, basalt
Deli t h (m)
i
s a n d g r a v e l Semi-consotis a n d s t o n e d a t e d sandgravel p e t i t e
w i t h d e p t h of 1000 C0-20m s
g r a n i t e , d i a . 3/4”
< r o t a r y method
>-
is
sand
Using t h e
with r o r e b i t s ) the
579
B = 0 . 5 3 X 1 X 1 . 8 9 x 3 7 . 4 2 ~2 0 + 2 . 8 6 X 1 X 1 . 4 5 X 3 7 . 4 2 X 8 0 C m ) = 131.64 Comprehensive cost for one meter CEO
)
is 1 3 1 . 6 4 US$ expenses is,
Using the downhole hammer drilling method the total
B =
0 . 5 3 X l x 1 . 8 9 X 3 7 . 4 2 X 204- 0. 25 :K 1 X 1.45:<37.42'.<5.
O X 80
= 749.67 + 5425-90 = 61.76 Comprehensive cost for one meter CE,) is 6 1 . 7 6 US$ Comprehensive
hydrogeological
work c o s t s per one
month
are
shown in Table 7
Geology investigation
I tens
in field
I
1. Personne 1 2. Mat er i a1 3 Amor t i zation 4.Repairing 5 . Transport 6.Other direct expenses 7. Manngement
I
Water analyses
distur -bu ted sample
in office I
0.04
Total
soil engineering analyses imdisturbu tcd sample
I
2.0
0.04
0.2
long-term observat ion work
6.0
61.7 11.8
6.4 13.4 15.5
6.4 4.3 15.5
0.02 0.01 0.01
0.1 0.1 0.4
0.4 0.3 1.3
10- 7 25. 2 10.7
27.9
23.6
0.05
0.0
2.4
32.7
0.26
4.0
112.0
138.8 1 1 1 3 . 9
I
I
163.5
China Geo-Engineering Corporation
Geo-Exploration
Corporation, has
been
Water
well
is a large professional state-owned enterprise
supply
cowltries Somalia,
Engineering
registered as economical and legal entity.
years, CGC has constructed about 1 0 0 water
thirty water
and
of
and Asia,
Africa
and Latin
America,
Mozambique, Nigeria, Bukkin,
which
the
well
in
mineral exploration projects
Sanegal,
In
past
dri 1 ing,
thirty
such
as
more Mali,
Eth op i a,
Faso,
Pakistan, Sri Lanka, Peru and so on. of 4 5 0 water and Sikasso) in Mali. 1. Drilling
It the
wells
in rural areas CFana, Kamtiata
is financod by the World Bank. The average depth is total
drilling
diameter 9 7/8-12
1/4
footage
27000m <900flm
inch,and rotary drilling
is
60m and
sediment
method;
180000
wit11 in
580
sandshale with project began
diameter 1.2 inch and downhole hammer method). Thr in November 1985. Because of high drilling
efficiency
or 2,074,011.5 US$
106-4 W S $ 2. The Construction of 485 Tubewells Projcc t
It is
The cost per one meter in South Rohri
has been financed by the Asia Bank. Average depth of
47.5m
with installation o f 8“- 12” pipes and
is
screens.
welts Total
drilling footage is 23239.301 and total price of contract
wilt be ending in two years. 3.Tlie Construction of 300 Tubewells in North and Extreme-North Provinces in Cameroon. This project is financed by the World Bank. CGC began the project in September 1987 with total drillings of 21342n arid total price of contract (including pipe) of 804,815,000 FCFA or 2,728, 186 US$. The cost per each meter i s 127,83 U S $ . &‘The Water Resource Exploration and Well Drilling in Puttatan and Chilaw towris, Sri Lanka. The project was commenced in October 10, 1985 and completed in Jime,1987. The exploratory wells of 5 3 and production welts of 21 with tube dia. o f 24.7-32.5cm were drilled-The total drilling footaye is 3048.28~. The total water ftowrate is 2895m’ld and allowable exploitative amount of underground water in both towns is 17992m’./d
Note, Karez A kind of irrigation construction in XinJian Region, Northwest Chiria. First,a.sr:ries of wells from the hit\ slope to the fields are
dug,
then, dig through in the
bottom of wells, make a
connection into the hidden channel t o draw the netted snow in mountain and underground t o irrigate the field.
the