DIA PHCONG
Khai thae vd bdo ve nirac duvi ddt
vung ven bien Dong bdng Nam Bo
Doin Vdn Cdnh
HOi Dia chS't Ihuy van Vj^l Nam
Nguyin Thae CUdng, Chdu TrSn Vinh
BO Ttli nguydn vJ M6i In/fmg
Sii khac nghiet ngay cang tang cua bien doi khi hau cimg nhQng dif an trfl niidc ndi thifdng nguon song MeKong da day dii dat ven bien Dong bang Nam Bp (DBNB) lam vao tinh cinh thieu nfldc ngpt tram trpng moi khi miia kho tdi, xam nhap man tran v l Dpt
h^n min hoi thing 3/2016 la mpt vi dM dien hinh, hdn 500.000 ngUdi phii sdng trong cinh thieu nUde ngpt dai ngay... Tuy nhien, theo tinh toin cua eac nha khoa hpc, neu biet each khai thie hpp ly ngudn tai nguyen nfldc di/di dat, DBNB hoan toan cd khi nang dim bio dii niidc ngpt cho ngiidi din sii dung quanh nam. Thong qua kit qui nghien cilfu vdi s6 iipu eg the, bai viet se cho chung ta thiy ro hdn ein cii eiia ket luan nay.
niai aaai ahic i a n i i t kha vat vaa Vung ven biln DBNB tU Bd Rja - Vung Tau d i n Ha Tidn cd tdi nguydn nudc dUdi ddt rdt phong phu nhung phdn bd khdng gian vd chilu sdu rlt khdc nhau. Td mat dit d i n dd sau 450 m, d day tin tgi 6 tdng chda nude dUpc ky hidu la q p , qp^ qp,. n/. n^ vk n' hoan toan ed t h l dap dng nhu cdu sd dyng nude in udng sinh hogt cho cdng ddng dan cu trong nhOng mua md ddng chdy trdn mdt bj nudc biln xdm nhdp vdo sdu. Tdng chda nude Pleistocen trung - thupng (qPjJ la tdng chda nudc dang dUpe khai thae mgnh nhdt tgi TP H i Chi Minh. Trd Vinh, Sdc Trdng, Bgc Lidu, Cd Mau vd Kidn Giang. Tdng chUa nudc
Pliocen (n,', n^') vd Miocene (n,') Igi dupc khai thae chu y l u d tinh Long An, Tiln Giang vd B i n Tre.
Tuy nhidn, tdi nguydn nude ngpt dudi ddt trong cdc tdng chda nude ndu trdn phdn b l dudi dgng cdc thdu kinh ddng kin, hinh thdnh ehu y l u td ngudn tich chda trong dd, khdng cd ngudn b i cdp ty nhidn, cho ndn cdn phdi ed gidi phdp khai thdc hpp ly, ddng tdng chda nude, ddng dd sdu phdn b l , ding thdi phdi di kdm theo gidi phdp b i sung nhdn tgo d l bdo vd tdi nguydn nude trude nguy cd cgn kidt va nudc mdn xdm nhdp vdo Idn chilm didn tich phan b l nudc ngpt.
o l lam sdng td khd ndng khai thae, sd dyng b i n vUng tdi nguydn nUde dudi dit, dya vdo
d$e dilm dja chit thdy van, hidn trgng phdn b l nude ngpt, nude m$n trong cdc tdng chda nudc trdn didn tich nghidn cdu, bdng cdch ehdng ghep cdc bdn dd dja chdt thuy vdn vk d l d l dang cho vide khai thdc sd dung tdi nguydn nudc dudi ddt, chung tdi phdn chia didn tich nghidn cdu ra ldm 6 vung vdi sif cd mdt nhilu hay it cdc tdng chda nude ngpt d cdc dd sdu khac nhau. Trdn bdn d l dd:
+ Vdng cd t h l khai thae td 4 d i n 5 tdng chda nude ngpt: td mdu xanh nudc biln ddm.
+ Vung cd t h l khai thdc 3 tdng chda nudc ngpt: td mdu xanh nude biln ddm vda.
+ Vung cd t h l khai thae 2 tdng chda nudc ngpt: td mau xanh
M KMMHQC
nfmfT|iBi# S611 nam 2016
DIA PHUONC
Sd dS phin vung dinh hudng si dgng hgp ly ngudn nudc dudi dit vung ven biin DBNB
nude biln nhgt.
+ Vung cd t h l khai thdc 1 tdng chda nude ngpt: td mau xanh Id cdy nhgt.
+ Vung cd t h l khai thae nudc 10: td mdu hdng.
+ Vung chi cd nude mdn td mau dd.
Vung ehl cd 01 tdng chda nude qpj chda nudc ngpt phan b l d thj trdn huydn Thgnh Phu - Bin Tre, phia Bdc tinh Trd Vinh va 2 khodnh nhd d huydn Hdn Ddt vd Kidn LUdng. tinh Kidn Giang. 6 ddy cd t h l khai thdc nude ngpt dudi ddt d dd sdu 100 m trd Igi bdng cdc l6 khoan ddn Id hode cdng trinh khai thdc nudc tdp
trung gdm nhilu l5 khoan.
Vung cd 2 tdng chda nude ngpt k l tilp nhau phdn b l chu y l u d tinh Bgc Lidu vd Ca Mau (qPj,.3, qp,: dd sau 150-250 m);
Long An vd Tiln Giang ( n / , n^,':
dd sau 250-350 m). d ddy cd t h l khai thdc nude dudi ddt bdng cdc l l khoan ddn l l hode cdng trinh khai thdc nudc tdp trung gdm nhilu l l khoan.
Vung ed 3 t i n g chda nudc ngpt lidn tyc td trdn xudng dudi phdn b l d TP Hd Chi Minh, Trd Vinh, Sde Trdng, Bae Lidu, Cd Mau va mdt phdn phia ddng tinh Kidn Giang. d ddy ed t h l khai thdc nudc dudi ddt trong tdng n,', nj' va n,3 d dd sau 150-200
m, 250-300 m vd > 350 m. Quy md khai thae cd t h l bdng cac l l khoan ddn l l ho$c cdng trinh khai thdc nudc tdp trung g I m nhilu l6 khoan trong mdt tdng hay trong nhilu tdng chda nude d dd sdu khdc nhau.
Vung cd 4 hode 5 tdng chda nudc ngpt lidn tyc td trdn xudng dudi phdn bd d TP Hd Chi Minh, Trd Vinh, Sdc Trdng, Bgc Lidu vd Cd Mau. d ddy cd t h l khai thae nudc dudi ddt trong tdng qp^^, qp,, n / va n^' d dd sdu 80-120 m, 150-200 m vd 250-300 m vd >
350 m. Quy md khai thdc cd t h l bdng cac l5 khoan ddn l l hode cdng trinh khai thdc nude tdp trung gdm nhilu l l khoan trong mdt tdng hay trong nhilu tdng chda nudc 6 dd sdu khac nhau.
Tilm nang nude dudi d i t va trO lupng ed t h l khai thdc nudc dudi ddt eac tdng chda nudc vdng nghidn cdu dupc trinh bdy trong bdng 1. Theo dd, ting tilm ndng nudc dudi ddt tich chda trong cdc t i n g chda nudc vdng ven biln Nam Bd la 100.536.510 ngan m' (100,54 ty m'), trong dd trO lupng cd t h l khai thdc la 3.016.000,1 mVngdy (3,02 tridu m'/ngdy), nghTa la n l u m i l ngdy chung ta khai thae sd dyng 3,02 tridu m^
nudc sd khdng gdy tdc ddng xdu d i n mdi trudng, khdng gdy cgn kidt ngudn nUdc.
Theo s l Hdu thing kd d i n ndm 2014, hidn trgng khai thdc nudc dudi ddt vung ven biln DBNB la 699.771 mVngdy. N l u cdng sudt khai thdc nhu t h l , du khdng cd ngudn b l sung nhdn tgo, thi tilm nang nude dUdI d i t cd t h l bdo ddm cdp nudc trong vung gdn 394 nam nda.
Stf n ry5m2016
ISlNGIWHlVietl'^
DIA PHUONG
Bing 1 tdng hgp Him ning tai nguyin va trO luang co ttii khai Ihic nudc dudi dit cda dc ting chUa nudc vung ven biin DBNB thUOng xuyin bi xim nhip min
TrO lima T<ng
TT ChOa NOI phin b<
nuac
TPHCM
' * • Trd Vmh. S6c Trang
n , ^ Ting kli6l lu^ng
^1 liifngnuac Tl&nning c6th^
v ? tichchila nu6cdi<6i khai ' ^ trong dng dft(ngta thie ,. - chuknUSc mVngiy) (ngin v ? tichchila nu6cdi<6i khai ' ^ trong ting dit (ngin thie rkmJi chiJanuac mVngiy) (ngii (nginm") mV ,
ngiy)
Khi ning khai thie
' Quy ni6 nh6, dS 710.680,00 71.07 21.32 bj nhiin bin do 1$
lin Irin mil dll.
669.700,00 730 630.00
66,97
73,06 21,92
Ouy mi nhd, dS bj nhiim m$n.
Quy mi nh6, d i bj nhiim m$n.
880 2.729.670,00 1.550 6.236.790.00
272,97 81.89 623,68 187,10l
TPHCM Tri Vmh j SAc Tring. B«c
Uiu, C i Mau, Klin Giang
TPHCM Long An. Tiin
Giang Bin Tre Sic Tring, B^c
Uiu, C i Mau.
Klin Qiang
10.500 32.091.880,00 3.209.19 962,76 NUdc ngpl phin bi audi d^ng Ihlu
;97o w . ^ 3 ^ J^ni^lrniVci
390 1.388.970,00 138,90 41,67 ""^ ""*" ™ "*'"
" nhip mJn, 7.250 13 746 000,00 1.374,60 412,38 Cin chu y phin
bi cic giing khoan khai Ihic, 1,200 3.126.880,00 312,69 93,81 luu luflng khai
Ihac hpp ly;
1 400 5.787,600.00 578,76 173,63
Vung ning Ihin:
60 263,700,00 26.37 7,91 Cic i i khoan khai Ihic vdi quy md til 20 m'/h din 50
TPHCM Long An, Tiin
Giang Bin Tre, Tra
Vmh Sic Tring, Bfc
Liiu, C i Mau TPHCM Long An, Tiin
Giang
5 200 14 327 040,00 1.432,70 429.81 rii'/h' 211,85
1.0001 2.118.460,00 63,55 Tpi cic thinh phd, Ihj xi, Ihl Irin 1 lOOi 2.184.600.00 21846 65 54 ''*" cic i i khoan cdng nghiip vdi 11.38 3,41 sOm'Di.
80 113,760.001 1800 3.288.600,00
720 1 846.800,00
328.86 96,66 184.68 55.40
Bin Tre Sdc Tring. Bae
LJiu, C i Mau Ting
1 8 2 0 4.105,920.00 410.59 123,18 437 j 849,530.00 84.95 25,49
660 2.317,920,00, 231.79 69,54
-L
100,536.510,00 i 10.053,65 3.016,10
Cic nil ihia hit Vi aMc ia« lii
Nhin chung myc nudc dudi ddt trong cdc tdng chda vdng DBNB cd xu t h l hg thdp. Theo tdi lidu cdng b l cua Trung tdm cdnh bdo va du bao tai nguydn nudc thdng 4/2016, myc nude ddng sdu nhdt hidn nay quan trdc dupe d TP H i Chi Minh trong tdng chda nudc qpjj la gdn 42 m. Mifc nudc trong cdc tdng chda nudc khdc vung ven biln OBNB theo quan trdc chuli s l lidu 10 ndm, mii nam hg thdp xuIng 1 m, nhung chua sdu qud 32 m, cdn xa so vdi ngUdng myc nudc ddng cho phdp khai thdc d i n mdi tdng chda nudc, hode t i l thilu theo cdng nghd khai thdc hidn tgi Id 50 m cdch m$t ddt. Tuy nhidn nhU da trinh bdy d trdn, nUdc ngpt d ddy t i n tgi trong cdc thdu kinh ddng kin, xung quanh bao bpc bdi nudc mdn, n l u khdng cd gidi phdp b i sung nhdn tgo trO lupng thi hg thdp myc nudc ddng theo xu hudng tang hdng nam sd ddn d i n didn tich thdu kinh nude ngpt bj thu hep, nudc mdn xdm nhdp vao vung nudc ngpt, ldm cgn kidt nguIn nudc ngpt trong tUdng lai.
Vi vdy, song song vdi vide khai thdc hpp ly, cdn thyc hidn cdc gidi phdp phu hpp sau:
+ Quy hogch bai giing khai thdc nudc dudi ddt. Nhu da trinh bdy d trdn, vung ven biln OBNB nudc ngpt phdn b l dudi dgng thdu kinh, hdu h i t bj ddng kin (chdn vui) khdng nhdn dupc sif b6 cdp hidn dgi. Trong nhOng vung nay cdc giing khoan khai thae ndn phdn b l d trung tdm t h i u kinh nudc ngpt. O l gidm thilu xdm
KSiSiiVeiItU
S d n nam2016DIA PHUONG
Thu gom nudc mua di dua vio Idng dii ii mil each bd sung nudc dudi dit
nhdp mdn dUdng nhidn lUdng khai thdc khdng dupe vUpt qua trd lupng khai thdc an todn (trd lupng cd t h l khai thae). Va d ddy nlu cung mdt lue khai thdc nudc ngpt phye vy an udng sinh hogt, ding thdi vdi vide khai thae nude m$n phye vy nudi trdng thdy sdn, thl hai ngudn nudc sd cd si,r cdn bdng, bdo ddm ngudn nude ngpt I n djnh hdn.
+ Ddy mgnh cdng tdc dilu tra, ddnh gia va ddnh gid Igi tdi nguydn nude dUdi ddt, Uu tidn thyc hidn trudc ddi vdi nhdng khu vyc cd nguy cd d nhilm, xdm nhdp m$n eao, khu vyc cd nhu cdu khai thdc dang tdng mgnh dd Id cdc tinh Cd Mau, Bgc Lidu, Sde Trdng, khu vyc nudc dudi dat khdng cd ngudn b i cdp thudng xuydn.
+ Nghidn cdu xdy dyng bdn dd djnh hudng khai thdc tai nguydn nudc dudi ddt ty Id 1:50.000 vd Idn hdn trdn didn tich tinh, thanh
phd... phye vy khai thdc b i n vdng vd bdo vd tai nguydn nudc dudi ddt.
+ Tdng cudng gidi phap b i sung nhdn tgo cho nudc dUdi ddt bdng cdch thu gom nude mua td cdc nhd cao tdng, dUdng p h i , sdn vdn ddng, nhdng khodnh ddt trdng... thoat xudng tdng chda nudc, mpt mat Idp ddy khodng khdng gian tdng chda nude "bj thao khd" do ha thdp mye nudc trong qua trinh khai thdc, hode dua vdo didn tich nudc mdn d l ldm nhgt nudc, mdt khac gian tilp gidm dng ngdp trdn mdt ddt.
Nudc mua thu gom td mdi nhd cd chdt lupng hodn toan thda man vdi ydu cdu nude dung lam ngudn phye vu cap nude. Nudc trdn via hd, dudng p h i , trudc khi cho thoat xudng dudi Idng ddt cdn tdp trung trong cae giao thdng hao, h i dao d l Idng Ipc Sd bd. Gidi phap ndy n l u dupc thye hidn se nhu "bdn mdt mui tdn trung hai dich". Mdt mat thoat dupc nudc mua nhanh
ehdng xuong Idng dat ngay tgi vj tri dng ngdp bdng nhdng cdng trinh ddn gidn, khdng chilm didn tich tren mdt, mat khac chinh lupng nudc dd cd t h l b i sung cho phan nudc dudi dat da bj Idy di.
Rat nhieu nudc trdn t h l gidi da dung bidn phap nay d l gdp phdn ching dng ngdp mdt ddt vd b i sung phdn trd lUpng nudc dUdi dat da bj l l y di. Cae bdng ehdng khdo c i cung cho thdy, vide thu gom nudc mUa da dupe ngudi XUa quan tdm td hdn 4.000 ndm trudc.
+ Quy hogch xdy di/ng dd thj:
d nhdng ndi phdn b l t i n g chda nudc, md nude dudi ddt dang dupe khai thae sd dyng thl khdng ndn xdy di^ng cdc nha cao tdng cd mdng sdu vdo tdng chda nudc lam gidm t h l tich chda nude, ngan cdn luu thdng nude. Kiln nghj dua vide thu gom nude mua tdp trung trong hdm chda vd b i sung vdo Idng d i t trong cdc quy chuln xdy dung d Vidt Nam ^ Til Hia tham khia
1) Ooin Vin Cinh, Nguyin Thj Thanh Thuy (2008). "Thu gom nadc mua dua vio idng d l l b i sung nhin t^o cho nudc dudi d l l v i ehdng ung ngip Ihinh phd", NXB Khoa hpc v i Ky thuit, 108 trang.
2) Ooin Vin Cinh (2015), "Nghiin djlu d i xull cic liiu chi v i phin vung khai thie bin vOng, bio v i tii nguyin nudc du& d l l vung Oing bing Bic Bd v i Odng bing Nam Bd', Bio cio ting kit di tii KCOB.06/11-
IS.cd quan chij Iri: Tn/dng O^i hpc Md - 0|a chit. H i Ndi, 260 trang.
3) Nudc dudi dit DBNB (1993). Owe Oja chit v i khoing sin Viit Nam, 163 Irang,
4) Groundwater Resouces Sustainability Indicators, UNESCO IHP-Vl Senes on Groundwater No, 14,
S 6 n r v 5 m 2 0 , 6 | 5 « J J 2 ; ( V j ^ | \ J 3 n i
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