groundwater
DESCRIPTION
Groundwater. Our hidden assetTRANSCRIPT
![Page 1: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/1.jpg)
National University of Malaysia
1
Groundwater (Our Hidden Asset)
Class: Special lecture II for Regular Course 5th grade students
Oct. 9th (WED) 15:35-16:20
28-Jan-14
Wan Zuhairi Wan Yaacob (Assoc. Prof, PhD) Faculty of Science and Technology
National University of Malaysia 43600 Bangi, Selangor, MALAYSIA.
![Page 2: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/2.jpg)
National University of Malaysia
β’ What is Groundwater
β’ Groundwater as a resource
β’ Groundwater and Geotechnical Problems
β’ Groundwater movement in soil
β’ Conclusion
28-Jan-14 2
Content:
![Page 3: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/3.jpg)
National University of Malaysia
28-Jan-14 3
What is Groundwater?
![Page 4: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/4.jpg)
National University of Malaysia
4
Two Types of Water
28-Jan-14
Hydrogeology (Groundwater) Subsurface water
Hydrology (Surface water)
Unsaturated
Saturated
Water table
![Page 5: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/5.jpg)
National University of Malaysia Groundwater
β’ Groundwater is a water that is found underground and is stored in the pore spaces (between grains) of porous geologic formation called an βaquiferβ.
β’ The importance of groundwater is easily overlooked.
β’ Groundwater is a hidden asset, out-of-sight and out-of-mind.
Water Cycle
28-Jan-14 5
![Page 6: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/6.jpg)
National University of Malaysia
Groundwater
6 28-Jan-14
Piezometric surface
β’ Aquifer (permeable) β’ Aquitard (Impermeable) β’ Artesian well β’ Water table β’ Piezometric surface
![Page 7: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/7.jpg)
National University of Malaysia
28-Jan-14 7
Groundwater as a Resource
![Page 8: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/8.jpg)
National University of Malaysia
Groundwater and the worldβs freshwater supply
"...Altogether, (groundwater) aquifers store 97% of the planet's (available) freshwater."
8 28-Jan-14
![Page 9: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/9.jpg)
National University of Malaysia
Water Usage in Large Cities in the World
9 28-Jan-14
![Page 10: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/10.jpg)
National University of Malaysia
Water Usage in Malaysia
35
5
60
Groundwater utilization by sector
Industrial
Agricultural
Domestic
3
97
Water use by source
Groundwater
Surface water
10
Surface water
Ground water
β’ Japan (13%) β’ South Korea (32%)
28-Jan-14
![Page 11: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/11.jpg)
National University of Malaysia
β’ Kelantan : 70% of its water source is from groundwater.
Groundwater
11
βAir Kelantanβ
Production well
Crystal clear groundwater
Privately owned tube well
28-Jan-14
My hometown
![Page 12: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/12.jpg)
National University of Malaysia
28-Jan-14 12
Surface water vs Groundwater
Slide from Dr. Saim Suratman (NAHRIM, Malaysia)
![Page 13: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/13.jpg)
National University of Malaysia
13
Source: Dr Saim Suratman, NAHRIM
Sg. Langat, Selangor
Sg. Jeli, Kelantan
SW GW
SW GW
28-Jan-14
![Page 14: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/14.jpg)
National University of Malaysia
28-Jan-14 14
Bank Infiltration
Fresh Water
River Water
Type of filtration that works by passing water to be purified for use as drinking water through the banks of a river or lake.
![Page 15: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/15.jpg)
National University of Malaysia
Source: Dr Azuhan Mohamed, Groundwater Expert.
Groundwater !!
28-Jan-14 15
This is what people normally see This is what people should be able to see
![Page 16: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/16.jpg)
National University of Malaysia
28-Jan-14 16
![Page 17: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/17.jpg)
National University of Malaysia
17
Source: Dr Azuhan Mohamed, Groundwater Expert.
28-Jan-14
![Page 18: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/18.jpg)
National University of Malaysia
28-Jan-14 18
Groundwater and Geotechnical Problems
![Page 19: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/19.jpg)
National University of Malaysia
1. Groundwater & Mining
19 28-Jan-14
Groundwater to mining engineer (eg. Penjom Gold Mine)
PENJOM GOLD MINE, MALAYSIA
How to manage the influx of groundwater into the open pit mine?
![Page 20: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/20.jpg)
National University of Malaysia
28-Jan-14 20
Vaiont Dam, Italy
2. Groundwater & Stability of Dam
Before After
![Page 21: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/21.jpg)
National University of Malaysia
Trigger factor: the fluctuation of groundwater level
Vaiont Dam, Italy
28-Jan-14 21
Slip surface
Water level before
Water level after
![Page 22: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/22.jpg)
National University of Malaysia
28-Jan-14 22
Trigger factor: the fluctuation of groundwater level
Ancient Slip surface
Water level before Water level after
Before
After
Dam Reservoir Old landslide area
![Page 23: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/23.jpg)
National University of Malaysia
28-Jan-14 23
Groundwater & Foundation
Expensive house
Crack developed under the house and surrounding area Problem: The foundation of the house failed,
Resulting cracks and unstable foundation.
![Page 24: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/24.jpg)
National University of Malaysia
28-Jan-14 24
Groundwater & Foundation
Reason for failure - Fill material = silt + gravel + boulder material - High K values - Channeling (old river) - Higher new water level/high water pressure
After development
Fill material
Retaining Wall
Before development
Original WT
Old river (diverted)
![Page 25: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/25.jpg)
National University of Malaysia
28-Jan-14 25
Groundwater & Foundation
![Page 26: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/26.jpg)
National University of Malaysia
28-Jan-14 26
Groundwater & Foundation Groundwater Modeling using Visual MODFLOW Pro
![Page 27: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/27.jpg)
National University of Malaysia
28-Jan-14 27
Groundwater Contamination
Groundwater Remediation at Taman Beringin Landfill site Malaysia
Drilling (boreholes)
![Page 28: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/28.jpg)
National University of Malaysia
28-Jan-14 28
Groundwater Contamination
Groundwater Remediation at Taman Beringin Landfill site Malaysia
![Page 29: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/29.jpg)
National University of Malaysia
28-Jan-14 29
Groundwater Remediation at Taman Beringin Landfill site Malaysia
Groundwater Modeling using Visual MODFLOW Pro
![Page 30: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/30.jpg)
National University of Malaysia
28-Jan-14 30
Groundwater Movement
![Page 31: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/31.jpg)
National University of Malaysia
31
A measure of how easily a fluid (e.g., water) can pass through a porous medium (e.g., soils)
Loose soil
- easy to flow
- high permeability
Dense soil
- difficult to flow
- low permeability
water
Hydraulic conductivity
28-Jan-14
![Page 32: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/32.jpg)
National University of Malaysia
Darcyβs Law
β’ Darcyβs experiment
β’ Henry Darcy
β’ French engineer
β’ 1856
28-Jan-14 32
![Page 33: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/33.jpg)
National University of Malaysia
Darcyβs Law
Z = 0 (Datum) Z1, Z2 Elevation of manometer h1, h2 Elevation of fluid βπ Distance of manometer
V (specific discharge) of cylinder
π =πΈ
π¨
π πΆ βπ
π πΆ π/βπ
E1
π πΆ (ππ β ππ)
28-Jan-14 33
![Page 34: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/34.jpg)
National University of Malaysia
Darcyβs Law
πΈ = V.A = (βπ ππ/ππ) . π¨
π πΆ β βπ π πΆ π/βπ
π πΆ β βπ/βπ
π = βπ βπ/βπ
π = βπ ππ/ππ
If ππ/ππ (constant); π πΆ π² ; π² = πππ ππππππ ππππ ππππππππ
E2
E2 E1
πΈ = βπ . π . π¨
-ve sign: the direction of flow is towards the
decreasing hydraulic head
28-Jan-14 34
![Page 35: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/35.jpg)
National University of Malaysia
Laboratory Field
- Manometer - piezometer
Borehole / Well
28-Jan-14 35
![Page 36: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/36.jpg)
National University of Malaysia
β’ A confined aquifer has a source of recharge.
β’ The discharge, Q = 37500 m3/day
β’ The piezometric head in two wells 1000 m apart is 55 m and 50
m respectively, from a common datum.
β’ The average thickness of the aquifer is 30 m, and the average
width is 5 km.
Example of Darcyβs Law
28-Jan-14 36
![Page 37: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/37.jpg)
National University of Malaysia Calculate:
(a) Calculate the hydraulic conductivity (K) ?
5 km
28-Jan-14 37
![Page 38: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/38.jpg)
National University of Malaysia
28-Jan-14 38
Solution
Cross-Sectional area (A) = 30(5)(1000) = 15 x 104
m2
Hydraulic gradient (i) = (55-50)/1000 = 5 x 10-3 (No unit / unit less)
Q = 37,500 m3/day Darcyβs Law, Q = k.i.A k = Q / i.A = (37500) / (5 x 10-3)(15 x 10
4 )
= 50 m/day (0.000578703704 m/sec) = 5.79 x 10-4 m/sec
![Page 39: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/39.jpg)
National University of Malaysia
28-Jan-14 39
50
![Page 40: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/40.jpg)
National University of Malaysia
int xn dx = xn + 1/(n + 1)
logex = 2.303 log10 x
π = 2.3
ππ‘ . πππ10
π2
π1
π (π§2 2 β π§1
2 )
Determination of permeability in the field
![Page 41: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/41.jpg)
National University of Malaysia
28-Jan-14 41
Example:
Pumping well Rate = Q
Observation well
Z1, Z2
r1,r2
π = 2.3
ππ‘ . πππ10
π2
π1
π (π§2 2 β π§1
2 )
![Page 42: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/42.jpg)
National University of Malaysia
Groundwater is precious as a clean water resource
Groundwater has implication on engineering structures and stabilities
Groundwater can pollute β need for better understanding about the groundwater safety
Movement of groundwater is govern by Darcyβs Law.
28-Jan-14 42
Conclusions
![Page 43: Groundwater](https://reader035.vdocuments.us/reader035/viewer/2022062405/5558f861d8b42ac04d8b48a6/html5/thumbnails/43.jpg)
National University of Malaysia
28-Jan-14 43
Thank you γ©γγγγγγ¨γγγγγΎγγ