Nghiên cứu sử dụng kỹ thuật đồng vị tự nhiên phục vụ đánh giá an toàn đập Đồng Mô

Bé khoa häc vµ c«ng nghÖ

ViÖn n¨ng l−îng nguyªn tö viÖt nam

B¸o c¸o tæng kÕt ®Ò tµi cÊp bé

Nghiªn cøu sö dông kü thuËt ®ång vÞ

tù nhiªn phôc vô ®¸nh gi¸ an toµn

®Ëp ®ång m«

Chñ nhiÖm ®Ò tµi: ths . bïi ®øc dòng

6611

24/10/2007

hµ néi - 2007

Bé khoa häc vµ c«ng nghÖ

ViÖn n¨ng l−îng nguyªn tö viÖt nam

B¸o c¸o tæng kÕt

®Ò tµi khoa häc c«ng nghÖ cÊp bé

n¨m 2005 - 2006

Nghiªn cøu sö dông kü thuËt ®ång vÞ tù nhiªn

phôc vô ®¸nh gi¸ an toµn ®Ëp §ång M«

(M sè B0/05/04-01)

C¬ quan chñ tr×: ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

Chñ nhiÖm ®Ò tµi: ThS., NCVC Bïi §¾c Dòng

Hµ Néi, th¸ng 9/2007

2

Danh s¸ch

Nh÷ng ng−êi tham gia thùc hiÖn ®Ò tµi

STT Hä vµ tªn Häc hµm,

häc vÞ,

chuyªn m«n

C¬ quan c«ng t¸c

1 Bïi §¾c Dòng NCVC, ThS ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

2 TrÞnh V¨n Gi¸p NCV, KS ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

3 Lª TiÕn Qu©n NCVC, KS ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

4 §Æng Anh Minh CN ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

5 §inh BÝch LiÔu CN ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

6 NguyÔn M¹nh Hïng KTV ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

7 Ph¹m Quèc Kû KTV ViÖn Khoa häc vµ Kü thuËt H¹t nh©n

8 T¹ Hång §øc KS Côc Thuû lîi, Bé N«ng nghiÖp vµ

Ph¸t triÓn N«ng th«n.

9 §Æng V¨n LËp KS C«ng ty khai th¸c c«ng tr×nh thuû lîi

Phï Sa- §ång M«

10 Phïng V¨n Lôc KS C«ng ty khai th¸c c«ng tr×nh thuû lîi

Phï Sa- §ång M«

C¸c c¬ quan, ®¬n vÞ phèi hîp thùc hiÖn ®Ò tµi

1. Côc Thuû lîi, Bé N«ng nghiÖp vµ Ph¸t triÓn N«ng th«n.

2. C«ng ty khai th¸c c«ng tr×nh thuû lîi Phï Sa- §ång M«, S¬n T©y, Hµ T©y.

3

môc lôc

Trang

B¶ng c¸c tõ viÕt t¾t 4

Abstract 5

Tãm t¾t néi dung 6

I. më ®Çu 7

II. Tæng quan tµi liÖu 10

2.1. T×nh h×nh nghiªn cøu trªn thÕ giíi. 10

2.2. T×nh h×nh nghiªn cøu trong n−íc. 12

2.3. C¬ së lý thuyÕt kü thuËt ®ång vÞ tù nhiªn 13

2.4. Tæng quan vÒ ®Ëp phô A vµ hå §ång M« 17

III. ph−¬ng ph¸p nghiªn cøu 23

3.1. ThiÕt kÕ nghiªn cøu 23

3.2. Néi dung nghiªn cøu 26

3.3. Ph−¬ng ph¸p nghiªn cøu 26

3.3.1. Ph−¬ng ph¸p lÊy mÉu vµ xö lý mÉu. 26

3.3.2. Ph−¬ng ph¸p ph©n tÝch mÉu 29

3.3.3. Ph−¬ng ph¸p xö lý sè liÖu vµ ®¸nh gi¸ kÕt qu¶ 30

IV. KÕt qu¶ nghiªn cøu vµ th¶o luËn 32

4.1. KÕt qu¶ quan tr¾c mùc n−íc thÊm 32

4.2. KÕt qu¶ ®o c¸c th«ng sè mÉu n−íc 34

4.3. KÕt qu¶ ph©n tÝch c¸c ®ång vÞ bÒn 35

4.4. KÕt qu¶ x¸c ®Þnh mèi liªn hÖ cña c¸c lo¹i n−íc 39

4.4. KÕt qu¶ x¸c ®Þnh tèc ®é thÊm 43

4.4. KÕt qu¶ ph©n tÝch ®ång vÞ phãng x¹ triti 44

4.5. KÕt qu¶ ph©n tÝch c¸c thµnh phÇn hãa häc 46

4.6. KÕt qu¶ ph©n tÝch c¸c th«ng sè m«i tr−êng 46

V. KÕt luËn vµ kiÕn nghÞ 48

5.1. KÕt luËn 48

5.2. KiÕn nghÞ 49

Tµi liÖu tham kh¶o 50

PhÇn Phô lôc 51

Phô lôc 1. KÕt qu¶ ph©n tÝch c¸c ®ång vÞ bÒn. 51

Phô lôc 2. KÕt qu¶ ph©n tÝch thµnh phÇn hãa häc 58

Phô lôc 3. B¶ng gi¶i tr×nh tµi chÝnh 60

4

B¶ng c¸c tõ viÕt t¾t

Ký hiÖu Gi¶i thÝch

KTHN Kü thuËt h¹t nh©n

§VTN §ång vÞ tù nhiªn

TV§V Thñy v¨n ®ång vÞ

IAEA C¬ quan N¨ng l−îng Nguyªn tö thÕ giíi

MS Khèi phæ kÕ tØ sè ®ång vÞ

TP§V Thµnh phÇn ®ång vÞ

δ

2Η(‰) TP§V 2H

δ

2Ο(‰) TP§V 18O

3H(T) Triti

TU Hµm l−îng triti. Mét TU t−¬ng øng víi mét nguyªn tö 3H

trong 1018 nguyªn tö hy®ro.

VSMOW MÉu tham chiÕu (reference) = Vienna Standard Mean

Ocean Water

GMWL §−êng n−íc khÝ t−îng toµn cÇu (Global Meteoric Water

Line).

5

Abstract

Operating and exploiting reservoirs need frequent monitoring and maintenance of

the problems affecting safety of the reservoirs’ dams. The §ång M« reservoir was

constructed in 1969. In 1984 at the sub dam A (FA) toe a seepage pond had

occurred with high charging rate, so this dam was repaired in 1991. However, the

seepage rate is still high, and in addition, there are large seepage areas that could

expand unsafe problems of the dam FA.

To help end-users generate information on the origin of the seepage water and the

seepage rate we have conducted a research project on “Research on the use of

environmental isotopes technique for safety assessment of the §ång M« reservoir”

(Code: B0/05/04-01) in the 2005-2006 period. The experiences gained in this project

are needed for recommending further use of the technique in other reservoirs. The

main works were collecting water samples, analyzing for 18O/16O, 2H(D)/1H ratios,

analyzing for 3H(T) and chemical contents, then drawing conclusions about the

origin of the seepage water and the seepage rate at the dam FA of the §ång M«

reservoir.

Findings of the project showed that: a) Waters at the piezometers on the top and the

1

st roof are not originated from lake water; b) Waters at the piezometers on 1st and

2

nd levels, as well as seepage waters at the dam toe are mixed of lake and ground

waters, and the old river bed could be the channel for ground water upcoming from

beneath the dam body; c) The transit times of water from the lake to the observation

points are from 3 to 4 months, and the seepage velocity is of about 1,1x10-3 cm/s; d)

The findings from tritium analyses show that all waters around the §ång M« area

are recent waters recharged regularly by meteoric water.

Based on the findings of the project we have recommended that the environmental

isotope technique be applied for further investigations of origin of leakage and

seepage water at other dams.