KHOA HOC CONG NGHE
DAIXIH G I A C H A T LUQIXIG IXIUIVC SOIXIG C A U DOAIXI C H A Y O U A TilXIH T H A I IXIGUYEIV, IVAHi B 0 1 9
Bin TO Thu^, Ngd Vidt Anh^ Nguyin Khde TTidnh^
T6MTAT
Nhdm danh gia chdt luong nude song Cau, nghien cuu dupe thuc hi$n tai 13 vi tri tr^n song Cau doan chay qua linh Thdi Nguyen vao thang 6 nam 2019. Ket qua cho thay, da so cac thong so chat lupng nude song Cdu diu ndm ti-ong gidi han cho phep cua QCVN 08-MT: 2015/BTNMT, mot so tiiong sd TSS, COD, BOD^, tong Fe vuot gidi han cho phep cua QCVN 08-MT: 2015/BTNMT tir 1,2 - 3,7 lan. Nhin chung, chat luong nude song a cac doan nghien cmi c6 su bien dong manh tir xau - trung binh - tdt; chi sd chat luong moi truong nude (WQI) dao dPng tir 35 - 88. He sd rdi ro mdi ti-udng (RQ) d mot sd doan song khong chiu anh hirdng true tiep tir cac ngudn thai co chat lugrtg tuong ddi tdt, gia tri RQ <1; mot sd doan song chay qua thanh phd Thai Nguyen, doan dan huyen Phu Binh co chat luong nude xau vdi gia tri RQ >1. Dilu nay cho thay can cd cac bi§n phap quan ly va bao ve tot hon chat lupng nude song Cau, dac biet la a cac khu vuc chiu anh budng cua mot sd ngudn thai smh hoat va sdn xuat cdng nghiep tren dia ban.
Tukhda: Chat luong nude, cbi sd chat luang nuoc, he sd rui ro moi tnidng, sdng Cau, tinh Thai Nguyin.
I.BATVANDE
Luu vue sdng Cau la mdt trong nhung luu vuc sdng ldn d phia Bdc nude ta, noi tdp trung ddng ddn cu sinh sdng d khu vuc phia Bdc. Sdng Cau dai 288,5 km bat ngudn tir nui Van On d do cao 1.175 km thugc huyen Chg- Ddn, tinh Bdc Kan ehay qua cac tinh/tiianh Bdc Kan, Thai Nguydn, Ha Ndi, Bdc Ninh, Bdc Giang va do vao sdng 11131 Bmh d thi xa Phd Lai, tinh Hai Dirong. Cae khu vuc sdng Cau chay qua la nhimg khu vue tap tnmg rat nhilu cac hoat ddng san xuat cdng nghiep nhin khai thac khodng san, luyen kim, ma dien,... Vi vay, tinh hmh d nhiim ndi chung va d nhiim mdi trudng nude mat ndi rieng dang d miic bao ddng [1,2].
Doan sdng Cau chay qua khu vue tinh Thdi Nguyin la nm dang ehu y bdi su tap tining cua eac doanh nghidp khai thac khoang san, cac cdng ty, eo sd san xuat hoat ddng vl linh virc luyen kim, cdc cdng ty det may va cac co sd ehe biln luong thue, thire pham hai ben bd sdng. Nude thai cua cac ddi tijgng nay mgt phan duoc thai true tiep ra sdng Cau vd cdc h i thdng sdng trong tinh ma chua qua xic ly.
Ciing vdi dd la viec sic dung hda chat va thudc bao ve thue vdt canh tdc ndng nghiep va khai thac cat sdi da ldm tang them d nhidm, sat Id vd bien ddi ddng chay.
' Trudng D^i hgc T^i nguyen va Moi trudng Ha Ndi
^ Hpc vien cao hpc Tmcmg Dai hoc Tai nguyen va Mdi tiirdng Hd Npi
Email: [email protected]
Chinh vi vay, nhiing nam gan ddy chat lugng ntrdc sdng Cdu doan chay qua thanh phd Thdi Nguyen dang bi suy giam [1,2].
D l xac dinh duge chat lugng ntrde sdng Cdu va anh hudng cua cae nguon thai tir hai ben bd sdng Cau doan ehay qua tinh Thai Nguyen tdi mdi trudng nude mat, nghien euu nay tap trung danh gid chat lugng nude sdng Cdu va danh gia anh hudng eua mgt sd ngudn thai chirdi din chat lugng nude sdng Cdu doan ehay qua tinh Thai Nguyen. Qua dd gdp phan cung cap eac sd lieu v l hien trang mdi trudng nude mat sdng Cau lam ea sd d l xuat mdt sd gidi phdp quan ly va bao ve ngudn nude mat tai dia phuong.
2. M l TUONG VA PHUONG PHAP NGHBU CUU 2.1. Ddi tirpng vd thdi gian nghidn cijcu Ddi tijgng nghien cim la mdi trudng nude mat sdng Cdu doan ehay qua tinh Thai Nguyen. Nghien eicu duoc thuc hien tir thang 5 den thang 10 nam 2019.
2.2. Phuong phap nghidn cihi 2.2.1. Phucmg phap lay miu
Mdu nude mat sdng Cau duoc lay doan chay qua ede huyen Phu Luong, tiianh phd Thai Nguyen;
Ddng Hy, Phu Binh, tinh Thai Nguyen tai 13 vi til, mdi vi til lay tij 01 - 03 mdu don. Mdu dugc lay tiieo hudng ddn cua TCVN 6663-1 : 2011 (ISO 5667-1 : 2006): Chdt lugng nude - Idy mdu - phdn 1: hudng ddn lap chuong tiinh lay mdu va ky tiiuat lay mdu; TCVN
10?
6663-6 : 2008 (ISO 5667-6 : 2005) : Chat luong nuoc - L^y mku - Phan 6: Humig dan lay mlu a song va suoi.
Mlu nuoc sau khi lay duoc bao quan theo TCVN 6663 - 3 : 2008 OSO 5667-3 : 2003): Chat lupng nuoc - L^y mlu - phan 3: huong din bao quan va xir ly mlu [3] va van chuyen ngay ve phong thi nghiem de phan tich.
Vi tri lay mSu nuoc song Cau duoc lua chon la cac vi tri CO chiu anh huong ctia mot so ngu6n thai cflng nghiep xan xuSt (nha may. cong ty co hoat dong san xuat cong nghiep, cac khu cong nghiep (KCN), cum cflng nghiep (CCN) trfln dia ban tinh Thai Nguyen. Vi tri lay mlu nuoc sflng Cau duoc mo ta chi tiet o bang 1.
TT 1 2 3
4 5 6 7 8
9
10
n
12
13
Ky hiflu mlu TNI TN2 TN3
TN4 TN5 TN6 TN7 TNB
TN9
TNIO
T N l l
TN12
TN13
Bang 1. Toa dfl vi tri 1 ^ mau nu6c mat sflne C4u Toa dp
21-43'49.26"N 105'49'34.66"E 2r39'59.62"N 105-47'28.06"E 2r38'18.82"N 105'48'6.42"E 21°37'2.32"N 105°48'29.47"E 21"36'45.99"N 105-49'12.29"E 21"36'4.87"N 105-5O29.87"E 2r35'31.2r'N 105"51'33.21"E 2r34'23.62"N 105"52'44.28"E 21-33'14.91"N 105-53'31.52"E 21'31'21.80"N 105-54'44.29"E 21-28'49.12"N 105'55'17.27"E 21-28'18.06"N 105'57'1.53"E 21"26'28.63»N 105'57'15.95"E
Dia diem lay mlu
Diem dau sflng Cau chay vao tinh Thai Nguyen, xa Hoa Binh, huyen Phii Luong.
Xa Vo Tranh, huyen Phu Luong, vi tri lay mlu gan Cong ty may Vina Sartup
Xa Son Cam, huyfln Phu Luong. Hpp luu song Du. Noi ti^p nhan ngufln thai smh hoat va nguon thai ciia cum cong nghiflp Du - Dong Da; cum cong nghiep Son Cim Thanh pho Thai Nguyen, vi tri lay mlu nuoc sflng Cau sau Cflng ty Co phan giay Hoang Van Thu
Thanh pho Thai Nguyen, vi tri lly mlu nuoc sflng Cau sau Cflng ty Nhiet dien Cao Ngan
Phuong Tiic Duyen, thanh pho Thai Nguyen. Diem tiep nhan nuoc thai sinh hoat tu cho Thai, cho Tiic Duyen, nuoc thai cua Cflng ty TNHH ung dung Cflng nghe BNQ Clu phao Huong Tmng, thanh pho Thai Nguyfln. Noi tiep nhan nuoc thai sinh hoat cua hoat dflng dan sinh.
Dap Ba Da, thanh pho Thai Nguyen. Day la noi co hoat dflng nong nghiep, nguoi dan sir dung nuoc song Cau cho muc dich tuoi tieu.
Clu Tra Vuon, phuong Cam Gia, thanh pho Thai Nguyen.
Vi tri lay mlu gan Cong ty Co phln cin thep Thai Trung, Cong ty Co phan Gang thep Thai Nguyen, Cong ty Co phan Hop kim sit gang thep Thai Nguyen.
Phuong Luong Son, di^m cudi chay qua thanh pho Thai Nguyen. Hai ben dong song co hoat dflng trong trpt cay hoa mau.
Xa Nha Long, huyen Phu Binh, Thai Nguyen. Diem tiep nhan nuoc thai sinh hoat va nuoc thai khu cong nghiep Diem Thuy, nha may kem dien phan Thai Nguyen, gan khu cflng nghiep thanh pho Sflng Cflng.
Clu May, huyen Phti Binh, tinh Thai Nguyen. Noi nguoi dan su dung nuoc sflng cho muc dich tuoi tieu cho hoat dflng trflng tiot hai ben sflng.
Xa lie Ky, huyen Phii Binh. tinh Thai Nguyen. Diem cudi cua song Cau chay qua diem cudi dia phan tinh Thai Nguyen.
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 4/2020
KHOA HOC CONG NGHE
2.2.2. Phuang phap phin tich tai phdng thi nghiim
Cac thdng sd mdi trudng nude mat pH, DO, nhidt do, dd due, TSS, BOD5, COD, amoni (NH4*), nihit (NO2), niti-at (NO3-), pholphat (^O^), cohform, clorua (CI), Cu, Pb, Cd, Zn, Fe dugc xac dinh theo cdc phuong phdp duge quy dinh trong Thdng tu sd 24/2017/TT-BTNMT: Thdng hr quy dinh ky thudt quan trdc mdi trudng trudng [3]; Thdng tir sd 21/2012/Tr_BTNMT quy dinh vifec bao dam chat lugng vd kiem soat chat Iuong ti-ong quan trdc mdi trudng [4].
Viec phdn tieh mdu dupe tiiue hidn tai Phdng thi nghiem Mdi tnrdng, Trudng Dai hgc Tdi nguydn vd Mdi trudng Ha Ndi. Phdng thi nghiem da dugc danh gid va cdp chung chi phu hgp vdi cdc yeu cau cua tidu chuan ISO/IEC 17025:2005, Unh vuc hda hgc ma sd VILAS 955 ngay 18/10/2016.
2.2.3. Phuang phap ddnh gia chat luang nude thing qua chisd WQI
Ddnh gid chat lirpng nude thdng qua viec tinh toan chi sd chat lugng nude WQI theo hudng ddn ciia Quydt dinh sd 1460/QD-TCMT ngdy 12 thdng 11 ndm 2019 cua Tong cue Mdi tnrdng [5]. Tinh todn WQI duge dp dung theo cdng thue sau:
nwe'j m-^Q'iA
|i2:wG/,.xi2:H'e/„j Trong do:WQIj: Kdt qua tinh toan ddi vdi thdng sd nhdm I (pH).
WQI,,; Kdt qua tinh todn ddi vdi eac thdng sd nhdm II (Aldnn, BHC, Dieldrin, DDT, (p,p'-DDT, p,p'-DDD, p,p'-DDE), Heptachlor &
Heptaehlorepoxide).
WQIni: Ket qua tinh todn ddi vdi cac thdng sd nhdm III (As, Cd, Pb, Cr^, Cu, Zn, Hg).
WQI^: Kdt qua tinh todn ddi vdi eac thdng sd nhdm IV DO, BOD5, COD, TOC, N-NH4, N-NO3, N- N02,P-P04).
WQIv: Ket qua tinh toan ddi vdi thdng sd nhdm V (coliform, E. coli).
2.2.4. Phuang phap danh gia rui ro mdi trudng He sd riii ro mdi trudng de md ta dac tinh rui ro ban dinh lugng. He sd rui ro (RQ) dugc tinh toan bang ty sd giira gia tri eiia edc thdng sd mdi tiirdng
xac dinh bdng do dac (MEC) hoac tinh todn du bdo (PEC) vdi gia tri du hao ngudng la gia tn d muc khdng gdy tae ddng (PNEC) len ddi tugng. PNEC duge xde dinh tir edc tieu ehuan, quy dinh hen quan.
RQ = MEC/PNEC. Khi: RQ tir 0,01 ddn 0,1 nii ro thap; RQ tir 0,1 den 1 riii ro trung binh; RQ >1 rui ro eao [6].
2.2.5. Phuang phap xir ly sd heu va danh gia kit qua
Kdt qua phdn tieh duoe ddi chieu vdi QCVN 08- MT : 2015/BTNMT- Quy chuan ky tiiuat Qude gia vd chat lugng nude mat [7].
Sd lieu nghien ciiu dugc xu ly bdng phdn mdm Excel.
3. KFT qUA NGHDI CUU VA THAO LUAN
3.1. TTidng ke mdt sd ngudn thdi san xudt cdng nghidp toi tinh tlidi Nguydn
Theo kdt qua thu thap sd lieu va didu tra thue td, hien tinh Thai Nguyen da cd 6 khu cdng nghiep (KCN) va 26 cum edng nghiep (CCN) duge Thii tudng Chinh phu phe duySt quy hoach chung vdi dien tieh la 1.420 ha. Hien ciing da ed khoang 150 dir dn di vdo hoat dgng, sd du an edn lai dang dau tu xdy dung hoat ddng ehu yeu trong linh vue san xuat didn, dien tit, cdng nghiep phu trg eho ngdnh san xudt dien, dien tir, eo khi che tao, det may vd cae Iinh vue dau tu khde.
Cac KCN, CCN dugc phdn bd ehu yeu b edc huyen Sdng Cdng, Phd Yen, Dinh Hda, Phu Luong, Ddng Hy, TP. Thai Nguyen, Phu Bmh [8]. Tai thdnh phd Sdng Cdng cd cae KCN Sdng Cdng I, KCN Sdng Cdng II, CCN Khuynh Thuong, CCN Nguydn Con, CCN Ba Xuyen; huyen Phd Yen ed KCN Nam Phd Yen, Tay Phd Yen, cac CCN Tan Trung - Thdng Thuong, CCN Van Thuong,...; huyen Dinh Hda cd CCN Trung Hgi, CCN Son Phu, CCN Kim Son;
huyen Phu Lirong cd CCN Du - Ddng Da, CCM Son Cdm; huyen Ddng Hy ed CCN Quang Son, Chi Son, Dai Khai; CCN Tan Lap, CCN Cao Nga b thanh phd Thai Nguyen va CCN Diem Thuy b huyen Phu Binh.
Cac KCN, CCN cd luu lugng xa thai tij khoang 90 ddn 16.000 m^/ ngay dem. Tdng lugng nude thai cua edc hoat ddng cdng nghiep ude tinh khoang hon 40.000 m^/ ngdy dem. Thdng sd thai ehu yeu tap tiimg vdo cac chi sd BOD5, COD, ^R^\ TSS [8, 1].
Tuy nhien, he thdng edng h-inh xu Iy nude thai tap tnmg hien chi ed KCN Sdng Cdng I vdi luong nude
sir dung hang ngdy vdo khoang 28 mVngay [9], cdn lai eae KCN, CCN khdc dang tien hanh xdy dimg hoae chua cd he tiidng xu ly nude thai. Tren dia bdn thdnh phd Thai Nguyen, ngudn nude sau khi sir dung duoc thai vdo cae sdng theo hai hinh thuc: xd vdo hd thdng cdng trinh xa cua khu - cum cdng nghiep, xa true tiep ra sdng va xa gidn tiep qua kenh muong, hd rdi thai ra sdng Cdu.
Ngodi cae ngudn thai edng nghiep, nude sdng Cau dang tiep nhdn mgt lugng ldn nude thai sinh hoat cua dan cu va hoat ddng eua cdc chg ldn tap trung hai ben sdng. Ude tinh lugng nude thai sinh hoat khoang 120.000 m^/ngdy dem. Lugng nude thai
sinh boat nay dirge xir ly qua bd tu hoai va dua vdo hd thdng thodt nude cua dia phirong rdi dd true tiep vao sdng Cdu vd cdc sdng khde trdn dia ban tinh [1]. Vi vdy, ed thd tiiay sdng Cau chay qua eae huyen Phu Luong, thdnh phd Thdi Nguyen. Ddng Hy, Phu Binh, tinh Thai Nguyen dang tiep nhdn nude thai cdng nghiep tir cdc KCN va CCN cung nhu tidp nhan mdt lugng Idn nude tiiai sinh boat tren dia ban ndi tren.
Cdc KCN, CCN tai cae huyen vd thanh phd Thai Nguyen dang cd anh hudng Idn den chat lirgng nude mat sdng Cau.
3.2. Hidn trang mdi tmdng nude m$t sdng Cdu doan chay qua tinh Tlidi Nguydn
TT 1 2 i 3 : 4 5
• 6
7 8 9 10 11 12 1 "
Kihieu mau TNI TN2 TNS TN4 TNS TN6 TN7 TN8 TN9 TNIO TNll TN12 TN13 1 QCVN08- ' MT:2015/BT
NMT (Bl)
Bang 2. K^t qua phSn tich chat lugn Nhiet
do
•c
25,8 29,0 26,4 26,5 27,4 27,4 29,1 29,8 29,1 29,3 28,4 27,2 30,3
pH
6,2 7,3 7,4 7.1 7,2 7.2 7,3 7,2 7,2 7.2 7.3 6,9 7,2 5,5-9
DO mg/L
5,7 5,3 5,9 5,8 5.8 5,8 5,3 5,8 6.0 6,0 5,8 6.7 6,0
>4 TSS mg/L 25 ±0,8 27+0,8 60 ±1,8 110 ±3,3 185 ±5.6 185 ±5.2 27+1,0 32 ±1,0 48± 1,5 41+1,2 74 ±1,5 36 ±1,0 23 ±0,8 50
COD mg02/L 24+0,8 49+1.5 41 ±1,2 74 ±2,3 50±1,5 48± 1,4 49 ±1,6 26 ±0,8 50± 1,5 44+1,4 66 ±2,0 26 ±0,8 35+1,0 30
g nu6c song Cau doan chay qua tinh T h ^ Nguyen BOD
mgO,/L 9 ±0,5 15+0.6 14 ±0,8 49 ±1,8 25 ±0,6 21 ±0,5 15 ±0,5 12 ±0,5 16 ±0,5 17 ±0,6 23+0,8 9 ±0,3 11 ±0,3
15 N-NH,*
mgN/L 0,14 0,29 0,29 0,50 0,90 0,36 0,29 0,23 0,60 0,21 0,30 0,60 0,16 0,9
P-PO,»^
mgP/L 0,082 0,070 0,080 0,180 0,200 0,090 0,070 0,037 0,300 0,018 0,078 0,047 0,026 0,3
N- NO.,- mgN/
L 0.88 1.23 0,62 0,83 0,73 0,73 1,23 0,98 0,70 0,12 1,03 0,39 0,89 10
Fe mg/L 0,538 0,814 2,953 1,354 2,742 2,740 0,814 0,719 0,978 0,590 1,476 0,469 0,371 1,5
Pb mg/L 0,003 0,003 0,016 0,014 0,012 0,012 0,003 0,003 0,008 0,004 0,006 0,002 0,009 0,05
Cd mg/L
<0,002 0,004 0,006 0,012 0,008 0,008 0,004
<0,002
<0,002
<0,002 0,006
<0,002
<0,002 0,01
Colilorm
MPN/
lOOmL 110 700 270 160 350 350 700 600 830 350 240 1500 1200 7500
50 — —
Hinh 1. Ham lupng TSS, COD, BOD5 trong nu6c sdng Cdu do?in chay qua tinh Thdi Nguydn
Khao sdt thuc te, hien nay nude sdng Cau doan ehay qua tinh Thdi Nguyen duge sir dung ehu ydu eho muc dieh tudi tidu, phue vu eho hoat ddng trong trgt hoa mau eua ngudi dan hai ben bd sdng. Vi v%y vide xac dinh gid tri cua mdt sd thdng sd nude mat sdng Cau doan chay qua tinh Thdi Nguydn dupe so sdnh vdi cdt B l (dimg cho mue dieh tudi tieu, thuy Igi) cua QCVN 08-MT : 2015/BTNMT [7]. Kdt qua dugc the hien b bang 2.
Ket qua d bang 2 cho thay hdu het edc vi tri lay mau, eae thdng sd dat gidi ban cho phep cua QCVN 08-MT:2015/BTNMT - Quy ehuan ky tiiudt Qude gia ve chat lugng nude mat, nhir pH, DO. N-NH/. N- NO3, CI, cohrfomi. tdng ddu ma mdt sd kim loai
KHOA HOC CONG NGHE nang nhu Pb, Cd. Ndng do oxi hda tan trong nude
(DO) dao ddng tir 5,3 - 6,7 mg/L tai 13 vi tri. Ndng dd N-NH4^ dao dgng tii 0,14 •- 0,9 mgN/L; nong do P- P04^ dao dOng tir 0,018 - 0,3 mgP/L; ndng dd CI- dao dpng tir 8 - 25 mg/L. Sd lugng coliform dao ddng tir 160 - 1500 MPN/lOOmL. Ket qua quan ti-dc nay khdng cd su dao ddng nhieu so vdi ket qua quan trdc cting thai diem vao nam 2018 cua Trung tam Quan trdc Mdi trudng, Tong cue Mdi trudng [10].
Hinh 1 eho thay, chat rdn \o limg (TSS) trong nude sdng Cau doan chay qua tinh Thai Nguyen dao ddng trong khoang 23 - 185 mg/L. Tai mgt sd vi tri, ham luong TSS vugt gidi han eho phep cua QCVN 08-MT : 2015/BTNMT tii 1,2 - 3,7 lan, tai cac vi tiri TN3 - TN6, day la eac vi tri sdng Cau ehay qua thdnh phd Thai Nguyen. Nguyen nhan ham Iuong TSS tang do cac mdu nude sdng b day tiep nhan cac ngudn nude thai tir Cdng ty Cd phan giay Hoang Van Tliu, Cdng ty Nhidt didn Cao Ngan, Cdng ty TNHH Ung dung cdng nghd BNQ,... va mdt sd cac ca sd san xuat khac tir thanh phd Thai Nguyen.
Gid til COD dao ddng tiJ 26- 74 mgO^/L. Mdt sd vi tri, gia tri COD vuot gidi han cho phep tir 1,2 - 2,5 lan d da sd cdc vi tri lay mdu nhu: TN2 - TN 7; TN9 - T N l l va TN13. Gid ti-j BOD5 ti-ong nude sdng Cau doan ehay qua tinh Thai Nguyen dao dgng tir 9 - 49 mgOa/L Gia tri BOD5 vuot gidi han cho phep tir 1,1 - 1,7 lan tai cdc vi tii TNS, TN6 vd TN9 - T N l l . Gid ti-i COD, BOD5 cao tai cac vi tri nay ngoai vide tiep nhan nude thai cua cdc cdng ty, nha may ndu tren, doan sdng qua thanh phd Thai Nguyen cdn tiep nhdn nude thai sinh hoat tir chg Thai, chg Tuc Duyen khien gid tri COD, BOD5 tang cao tai cac vi tri TNS, TN6. Doan song ehay qua huydn Phu Binh cting tiep nhan mdt lugng ldn nude thai sinh hoat vd nude thai eua Khu Cdng nghidp Di^m Thuy, Nha may Kem didn phan Thai Nguydn ciia Khu Cdng nghidp Sdng Cdng nen gia ti-i COD, BOD tai eac vi tri TNIO, T N l l cung tang so vdi cac vi tri khdc.
So sanh vdi nghien cuu cua Vu Thi Hdng Nghia, 2011 [11], nude sdng Cau tir vi tri xa Hda Binh den dap Thdc Hudng (tuong ung tir vi tii TNI ddn TN7 d nghien ciiu nay) ed dau hieu bj d nhidm. 0 nhifim kim loai nang tai mot sd didm nhu Son Cdm (img vdi vi til TN3), Hodng Van Thu (ting vdi vi til TN4), cau Trd Vudn (img vdi vi tri TN9) vugt gidi han cho phep ddi vdi ngudn nude loai A2. Tuy nhidn, nude sdng Can doan ehay qua tinh Thai Nguyen cd dau hidu
suy giam tir nam 2011 den 2019. Didu nay cho tiiay cac nha may edng nghiep, edc khu cdng nghiep ed anh hudng den chat lugng nude sdng Cdu.
Danh gid chat lugng nude mat tai Thai Nguyen theo ehi sd chat lugng nude (WQI) [7], gia tri WQI tai vi til TNI, TN2, TN7, TNB, TNIO, TN12, TN13 lan lugt bang 88, 82, 82, 88, 85, 88, chat lugng nude hiong ung mdu xanh. Tai TN 3, WQI = 69; TN6, WQI
= 55; TN9, WQI = 61; T N l l , WQI = 63, tai cdc vi tii nay chat luong nude sdng tuong ung vdi mdu vang.
Tai hai vi tri TN4 va TN5, gia tn WQI lan lugt bdng 35 va 35, chat lugng nude tai hai vi tri ndy tuong iing vdi mau da cam. Gid tri WQI tai cac diem quan trac dugc the hien d hinh 2.
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Thai Ngujen
c
4.,
s
Hmh 2. Ban do phdn vung chat lugmg nude sdng Cdu doan chay qua tinh Thdi Nguydn Ban do phan vimg chat lugng nude d hinh 2, cho thay sdng Cau doan dau chay vao tinh Thdi Nguyen qua huyen Phu Luong chat Iuong nude edn tuong ddi tot, cd the sic dung cho mue dieh cap nude sinh hoat nhung can cac bidn phap xif Iy phu hgp. Sdng Cau doan chdy qua ranh gidi thanh phd Thai Nguyen va huydn Ddng Hy, tiep nhan nhi^u ngudn nude thai cdng nghidp, nude thai sinh hoat ndn chat lugng nude sdng Cau suy giam, dac bidt ddi vdi eae vi tri sau nha may giay va nhidt didn (TN4, TN5) chat lugng nude sdng Cdu chi sii dung duoc cho muc dich giao ihdng thuy. Cac doan edn lai chat lugng nude sdng Cau phu hgp cho muc dich tudi tieu. Tai diem cudi sdng Cdu ehay qua dia phan tinh Thai Nguyen khdng tiep nhdn cdc nguon thai, chat lugng nude tuong ddi duoc cai thien.
Tir viee phan vimg chat lugng nude sdng Cdu d hinh 2 da eho thay mgt sd ngudn tiiai san xuat edng nghiep trdn dia ban tinh Thai Nguyen da cd anh hudng brue tiep den chdt lugng nude sdng Cdu. Tai 107
edc vi tri lay mau nude sdng Cau dang tiep nhdn ngudn thdi eua mdt sd KCN, CCN tren dia bdn tinh nhir vi tri TN 3 tiep nhan nude thai eiia CCN Du - Ddng Da, CCN Son Cam doan qua huydn Phu Luong; ddi vdi doan sdng Cdu chdy qua ranh gidi thdnh phd Thdi Nguyen vd huyen Ddng Hy, vi tri TN4, TNS, TN6 tiep nhdn nude thai eua nhieu nhd may san xuat, ciia CCN Cao Nga, KCN Quyet Thdng va mdt sd KCN, CCN thugc huyen Ddng Hy; vi tri TN9 tiep nhdn nude thai eua KCN va CCN thude thi xa Sdng Cdu vd huydn Phd Yen doan ddu ehay vao huydn Phu Binh, vi tri T N l l tiep nhan nude thai cua CCN Diem Thuy doan chay qua huydn Phu Binh.
Cdc vi tri nay chat lugng node sdng Cau dang ed dau hieu suy giam, theo ehi sd chat lugng nude WQI, chat lugng nude dugc bieu didn bdng mdu vdng, dac bidt tai vi tri TN4, TNS Id mau da cam.
So sdnh vdi nghien cuu cua Vu Thi Hdng Nghia, 2011 [11], viec tinh todn ehi sd WQI dua tren tinh toan ehi sd WQI hiiu c a (eho cdc thdng sd BOD^, COD, N H / , coliforrn), cho thay cdc doan sdng Cdu qua vi tri Hodng Van Thu (img vdi vi tri TN4 d
nghidn eihi nay), Cau Trd Vudn (ung vdi vi tri TN9), nude sdng d mue d nhidm trung binh (WQI ^ 6), edc vi tri cau Gia Bay, ddp TTidc Hudng (iing vdi vi tii TNT), nude sdng d muc d nhiem nhe (WQI = 4 - 6 ) , cdc doan cdn lai eua sdng Cdu qua tinh TTiai Nguyen khdng d nhidm. Ndu dtra vdo thdng sd kim loai, chi sd WQI tai vi tri Hodng Van Tliu (TN4) ed dau hieu 6 nhidm. Mac dii each tinh chi sd WQI cua tdc gid Vu Thi Hdng Nghia chua cd y nghia tdng hgp, nhung kdt qua nghien cuu khd tirang ddng tai mdt sd vi tri lay mdu so vdi nghien cuu nam 2019. Tai edc vi tri TNS, TN4, TNS, TN7, TN9 vdn cd ddu hidu d nhi§m tir nam 2011 den nay.
3.3. Ddnh gid nii ro mdi tnidng nude m$t sdng Cdu doan chay qua tinh Tlidi Nguydn
Ddnh gia anh hudng cua mdt sd nguon thai d^n chat lugng mdi tnrdng nude sdng Cdu doan chdy qua tinh Thai Nguyen thdng qua viec ddnh gia rui ro moi trudng nude sdng Cdu. Ket qua ddnh gia rui ro moi trudng nude sdng Cau doan chdy qua tinh Thdi Nguydn duoc trinh bdy qua bang 3.
TT 1 2 3 4 5 6 7 8 9 10 11 12 13 Danh do YU
Kihi$u mau TNI TN2 TNS TN4 TNS TN6 TN7 TNS TN9 TNIO T N l l TN12 TN13 gia miic
ro
Bang 3. H^ so rui ro nu6c sdng Ciu doan chay qua tinh Thdi Nguy^
TSS 0,5 0,54 1,2 2,2 3,7 3,7 0,54 0,64 0,96 0,82 1,48 0,72 0,46 T B - C
COD 0,8 1,63 1,37 2,47 1,67 1,6 1,63 0,87 1,67 1,47 2,2 0,87 1,17 T B - C
BOD 0,6
1 0,93 3,27 1,67 1,4 1 0,8 1,07 1,13 1,53 0,6 0,73 T B - C
N - NH,*
0,16 0,32 0,32 0,56 1 0,4 0,32 0,26 0,67 0,23 0,33 0,67 0,18 TB
Hft P-PO,'^
0,27 0,23 0,27 0,6 0,67 0,3 0,23 0,12 1 0,06 0,26 0,16 0,09 T - T B
soRQ N-NO,
0,09 0,12 0,06 0,08 0,07 0,07 0,12 0,1 0,07 0,01 0,1 0,04 0,09 T - T B
Fe 0,36 0,54 1,97 0,9 1,83 1,83 0,54 0,48 0,65 0,39 0,98 0,31 0,25 T B - C
Pb 0,06 0,06 0,32 0,28 0,24 0,24 0,06 0,06 0,16 0,08 0,12 0,04 0,18 T - T B
n
Cd
0,4 0,6 1,2 0,8 0,8 0,4
0,6
T B - C Cohlorm
0,01 0,09 0,04 0,02 0,05 0,05 0,09 0,08 0,11 0,05 0,03 0,2 0,16 T-TB Ghi chu: T: thap; TB: trung binh; C: cao
Bang 3 eho tiiay, ddi vdi eac thdng sd NH4'^, PO^^
, NO3", CI, Pb, tdng dau md, coliform, he sd nii ro (RQ) < 1, didu ndy tuong iing vdi trong mdi tnrdng nude sdng Can muc do rui ro ddi vdi cdc thdng sd
trdn Id thap - trung binh. Ddi vdi cdc thdng sd TSS, COD, BODS, Fe, Cd tai mdt sd vi iri he sd RQ > 1, cho thay miie do rui ro ddi vdi eae thdng so ndy Id nii ro cao. Theo cdc vi tri Idy mdu he sd rui ro RQ dao
KHOA HOC C d N G NGHE
ddng tii 0,24 - 1,00 tuong irng vdi mtic dd rui ro tiling binh. Gid bi RQ cao nhat tai vi tii TN4, TNS, dieu ndy eho thdy eac ngudn thai tai doan thdnh phd Thdi Nguydn cd anh hudng Idn den chdt lugng nude mdt sdng Cau.
Hd sd riii ro mdi tnrdng RQ >1 tdp trung tai 02 khu vue; khu vue 1 bao gdm edc vi tri TN3, TN4, TNS, TN6, day la cae vi tri sdng Can ehay qua thanh phd Thdi Nguyen, nude m$t sdng Cau tiep nhan ngudn thai cua mdt sd ede edng ty, eo sd san xuat cdng nghiep trdn dia ban thanh phd nhu Cdng ty Co phan giay Hoang Van Thu, Cdng ty Nhidt dien Cao Ngan, Cdng ty TNHH Ung dung cdng nghe BNQ,...
va tiep nhan nude thai sinh hoat tir mdt sd chg ldn cua thanh phd nhu cho Thai, chg Tuc Duyen. Khu vuc tiiii hai bao gdm edc vi tii TN9, TNIO, T N l l Id cac vi tri sdng Cdu tiep nhan nude thai tir Cdng ty Cd phan edn thep Thai Trung, Cdng ty Co phan Gang thep Thdi Nguydn, Cdng ty C6 phan Hop kim sdt gang tiiep Thdi Nguyen, KCN Didm Thuy, KCN thdnh phd Sdng Cdng,.... Cae ngudn thai ndy khien nude sdng Cau bi d nhidm cac thdng sd TSS, COD, BOD5, NH4% Fe, gdy rui ro mdi trudng cao, cd nguy CO anh hudng ddn siie khde ngudi ddn su dung nude song Cdu cho cdc muc dieh sinh hoat. Nhu vay cho thay mdt sd cac ngudn thai tii hoat dgng san xuat cdng nghiep tren dia ban tinh cd anh hudng nhdt dinh den chat lirpng nude sdng Cau.
Ket qua ddnh gia riii ro mdi tnrdng nude sdng Cdu cho thay, ddi vdi cac vi tri cd chi sd chdt lugng nude WQI trong cdc khoang 26 - 50 va 51 - 75 thi he so nii ro cua nhieu thdng sd trong mdi trudng nude ldn hon 1 (RQ >1). Didu nay eho thay chat lugng nude sdng Cdu ciia nhimg doan nay cd cac thdng sd vugt gidi han cho phdp cua QCVN, nude sdng cd nguy CO d nhiem tai cae doan sdng nay. Ddi vdi eac doan sdng, gia tri WQI >75 (tuong img chat lugng nude tdt) thi da sd cac tihidng sd ed hd sd RQ <1. Cae doan sdng nay hdu het cd cdc thdng sd dat gidi han eho phep cua QCVN 08-MT:2015/BTNMT.
4 . KET LUAN
Danh gid chat lirgng nude sdng Cdu doan chay qua tinh Thdi Nguydn nam 2019 cho thdy, da sd cac thdng sd ndm trong gidi ban eho phdp, mdt sd thdng sd TSS, COD, BODs, tdng Fe vugt gidi han eho phdp eua QCVN 08-MT: 2015/BTNMT tir 1,2 - 3,7 ldn tai mdt sd VI til nhu TN4, TNS, TN6. Day la nhimg doan nude sdng Cau chay qua thdnh phd Thai Nguyen
chiu anh hudng cua mdt sd ngudn thai san xuat cdng nghiep nhu Cdng ty Cd phdn giay Hoang Van Thu, Cdng ty Nhiet didn Cao Ngan, Cdng ty TNHH Ung dung cdng nghe BNQ.
Gia tri WQI dao ddng tii 35 - 88, chat lugng nude sdng tiiong iing b edc mirc: xau - trung binh- tdt Doan sdng Cau ehay qua huyen Phu Luong vi tri TNI, TN2, vi tii TN7, TN8 doan qua tiianh phd Tlidi Nguyen va TN12, TN13 doan cudi ehay qua huydn Phu Binh cd gid tii WQI = 82 - 88 tirang img chdt luong nirdc tdt; vi ti-i TN6 doan qua thanh phd, TN9 doan qua huyen Phu Binh cd gia tri WQI = S5-69 tuong ling chat lugng nude d miic trung binh. Doan sdng Cau chay qua thdnh phd Thai Nguydn TN4, TlsIS ed gia tri WQI = 33 - 3S, tuong ung chat lugng nude xau.
Mdt sd doan sdng khdng chiu anh hudng true tidp tii cdc ngudn thai cd chat lugng tuong ddi tdt cho he sd rui ro mdi trudng ddi vdi cdc thdng sd RQ <1;
mgt sd doan sdng nhu: doan ehay qua thdnh phd Thai Nguyen, doan dau huyen Phu Binh cd chat lugng nude xau, chi phuc vu cho muc dieh giao thdng thuy, he sd rui ro mdi trudng mdt sd thdng sd RQ>1.
LMCAMON
Bai bao duac hoan thanh dual suhd tra kinh phi cua de tai TNMT.2017.04.13. Cac tac gia xin ti-an trong cam an.
TAI LIEU THAM KHAO
1. Sd Tai nguyen va Mdi trudng Thai Nguyen (2016). Bao cdo hien trang mdi budng tinh Thai Nguyen giai doan 2011- 2015.
2. Gidi thieu chung vd lim vuc sdng Cdu (2016).
Cong tiidng tm quan trdc mdi trudng - Tdng cue Mdi trudng.
3. Thdng hi 24/2017/TT-BTNMT, Quy dinh ky tiiuat quan trdc mdi tiirdng.
4. Thdng tir so 21/2012/TT-BTNMT, Quy dinh viee bao dam chdt lugng va kiem soat chat luong trong quan trdc mdi trudng.
5. Quyet dinh sd 1460/QD-TCMT, Quyet dinh vd vide ban hdnh hudng dan ky thuat tinh toan va edng bd ehi sd chat lugng nude Viet Nam (VN_WQI).
6. Ld Thi Hdng Tran, 2008. Ddnh gid nii ro mdi tnrdng, Nha xudt ban Khoa hgc vd Ky thuat.
7. QCVN 08-Mr:2015/BTNMT - Quy chuan ky 10. Tong cue Moi tmcmg, Tnmg tam Quan trie thuat Quoc gia vi chat luong nuoc mat Moi truong, 2018. Bao cao tong hop lift qua q"an
8. Ban Quan ly cac khu cong nghiep Thai trie moi huong nuoc luu vuc song Ciu nam 2018.
Nguyta, 2019. Bqlkcnthainguyen.gov.vn 11. Vu Thi Hong Nghia (2011). Nghien cihi quan 9. Cue Quan ly tai nguySn nuoc (2016). Dieu tra '^ '=*'* '"™S •»«« song Ciu tren dia ban tinh T h a tinh hinh khai thac sd dung tai nguyen nude va xa Nguyen. Luan van thac sy nganh Khoa hoc moi nude thai vao ngudn nuoc luu vuc song Cau, Ha Noi. truong, Tniong Dai hoc Khoa hpc Tu nhien, nam
2011.
ASSESSMENT OF WATER QUALITY OF CAU RIVER THAT THROUGH THAI NGUYEN PROVINCE W 2019
Bui Thi Thu, Ngo Viet Anh, Nguyen Khac Thanh Summary
In order to assess the quality of Cau I?iver water, the study was conducted at 13 locaUons on the Cau nver that flows through Thai Nguyen province in June 2019. The results show that, most parameters insite Cau River surface water are within the permissible limits of QCVN 08-MT : 2015/MONRE. Some parameters such as TSS. COD, B0D5 and total Fe exceed the permissible limits of QCVN. 08-MT: 2015/MONRE from 1.2 to 3.7 times. In general, the water qualily m the study area was varied from bad, moderate and good.
The water quality index (WQI) ranges from 35 to 88. The environmental risk factor (RQ) in some river secUons are not directly affected by the waste sources, have good quahty (RQ < 1), while in some other secUons running through Phu Binh district, Thai Nguyen city, have bad water quality (RQ > 1). This indicates that better management and protection of Cau River water quality are needed, especially in areas affected by a number of domestic and industrial production sources.
Keywonis: Water quality, water quality index, environmental nsli factor, Cau nver. Thai Nguyen province.
NguM phdn b i ^ : GS.TS. Nguyta XuSn Cli Ngay nhJnbM; 6/3/2020
Ngiy thflng qua phan bi^n: 6/4/2020 Ng4y duyft dang: 13/4/2020
