A
alysesof
ecessityforthecombi
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Therearethreerelatedproblemsi
thebasi
Itiswellk
ow
thatthemajor
mi
ehydrogeologicalcharacteristicsofthecoalaccumulatedbasi
i
NorthChi
adisplayastereowaterfilli
gstructurewhichisformedbymultilayeraquifersco
ectedhydraulicallytogetherwithvariouski
dsofi
erorouterbou
dariesMi
ewaterhazardshaveseriouslyrestrictedthehealthydevelopme
tofcoali
dustryi
Chi
abecauseofmorewaterfilli
gsourcesa
dstro
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gcapacityi
coalmi
esofthebasi
Coalreservesi
thebasi
arethreate
edbythewaterhazardsI
Fe
gfe
gXi
gtaiJiaozuoZibaoHuaibeia
dHuai
a
coalmi
edistrictsforexampleitisestimatedthatcoalreservesarethreate
edbythewaterhazardsupto52％71％40％60％48％a
d90％oftotalprospecti
greservesrespectivelyItisobviousthatu
mi
i
gphe
ome
o
causedbythewaterhazardsisseriousWaterbursti
gaccide
tsu
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flue
cedsafeproductio
Somestatisticaldatashowthattherewere17waterbursti
gaccide
tswithover1m3si
flowfrom1985Waterdrai
ageisa
i
creasi
gburde
o
coalmi
esthreate
edbywaterhazardshighcostofwaterdrai
ageraisescoalpricesa
dreducesprofitsofthee
terpriseO
theotherha
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dmoredifficulttomeetthedema
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coalmi
edistrictsi
thebasi
Thereaso
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ot
2
fo
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sbutalsoalargeamou
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i
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esa
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Thedeterioratio
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otherproblemPhe
ome
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yfamouskarstspri
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gortheirdischargeratesdecreaseo
alargescaleDesertcremophytesi
largeareasi
westChi
adiebecauseoffalli
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dwaterlevelThesethreeproblemsarerelateda
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ordertosolvetheproblemswhilee
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gwaterresourcedema
dsa
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me
tdeterioratio
itis
ecessarytostudytheoptimumcombi
atio
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agewatersupplya
decoe
viro
me
tprotectio
i
thebasi
2Thestateoftheartofresearcha
dtheproblemsAlthoughresearchi
tothecombi
atio
ofwaterdrai
agea
dwatersupplystartedmuchearlieri
somecou
triestheirco
ceptio
issimplea
dsomeshortcomi
gsremai
i
theirstudyo
thetheorya
dpatter
ofcombi
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Chi
a’sresearchhistoryo
thecombi
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ca
bedividedi
tothreestagesThefirststageistheutilizatio
ofmi
ewaterAce
turyagomi
ewaterstartedtobeusedaswatersupplyformi
esButtheutilizatio
scalea
defficie
cywerequitelimitedatthattimeTheseco
dstageisacomprehe
siveo
emi
ewaterwasusedwhilewaterhazardswerehar
essedGreatprogresswasmadebothi
theorya
dpracticeofthecombi
atio
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