INSTRUCTIONS:

 Answer All Questions

 Indicate your NAME, INDEX NUMBER and DEPARTMENT

 Submit the assignments through this email:-
assignmentfluid@gmail.com
 No assignment must be submitted through my personal email.
 Assignments to be submitted by midnight of 26/06/2020.

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 NAME: SARPONG KOFI OWUSU
INDEX NUMBER: 5874416
DEPARTMENT OF CIVIL ENGINEERING
CE 458 – WATER RESOURCES ENGINEERING
Answer All Questions
Section A (State if the answer is True or False)

1. The Specific storage of a confined aquifer is the measure of its transmissivity. True

2. The amount of water retained in the interstices of a formation will depends on Aggregate
surface and size of the interstices. True

3. Steady-state solution is important in making a quick assessment of the influence zone of a

well. True

4. A steady state conditions is said to occur when there is no change in drawdown with time.
True

5. The radius of influence of a well is the maximum radius of the cone of depression for a well
operating under steady state condition. True

6. The Thiem’s model is used to analyse unsteady state pumping condition of an aquifer. False

7. The initial drawdown will be the same everywhere for all times of pumping for a study state
condition. True

8. Near a pumping well the flow toward the well is discharge. True

9. The Theis model is valid for values of u decreases as the time (t) of pumping increases and as
the radial distance (r) from the well decreases. True

10. Recovery is the process of observing pumping information in a well after sometime. True

11. The residual drawdown is the recharge to the well after pumping had stopped. True

12. When the water level in a well penetrating an aquifer rises above the ground surface is an
indication of the existence of an unconfined aquifer. False

13. For incompressible fluids the Darcy’s velocity will be the same as the groundwater velocity of
flow. False

14. Groundwater flow takes place in the direction from the higher pressure head a lower pressure
head. False

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 15. In the field, a Researcher investigating an aquifer realised that the aquifer is unconfined and
hence determined the specific yield of the aquifer. Giving presentation on his work, he
interpreted the specific yield as the specific storage. The Researcher was correct. False

16. The total drawdown in a pumping well is the sum of the drawdown in the pumping well and
the drawdown at the radius of influence of the well. False

17. As a Water Engineer, groundwater monitoring study will help you bridge knowledge gaps in
the general understanding of the resource and its changes in time. True

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Section B (Fill in the BLANK spaces)

1. The …water cycle... describes the continuous movement of water ……on, above… and …below….

the surface of the Earth.

2. …Groundwater…. is the portion …runoff…., which infiltration and through percolation, collects

underground.

3. An ……aquifer……. is a …geological formation…... that transmits and yields significant amount

of water.

4. …Effective porosity… is the portion of pore space in a saturated porous material in which water

flow occurs.

5. Groundwater is always in continuous slow movement from .... high hydraulic head...... areas

to.…. low hydraulic head........ areas.

6. …Specific storage…. defined as …volume of water……. that is released from or taken into storage

per unit volume of a confined aquifer layer per unit change in …hydraulic head…

7. Raw water development deals with …raw water collection…and…storage…….

8. …Operating yield…. is that supply that could be given under a fixed set of …operating…... rules.

9. Safe-yield is the …volume of water abstracted/extracted…. that the lowering of the

…water level…… becomes objectionable

10. Yield of a well ……is the highest pumping rate… at which water can be pumped out of a well

without causing drying up or failure of the well.

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Section C

a. Using the data collected on BOREHOLE PUMPTEST - DISCHARGE PERIOD and RECOVERY for
well drilled in ASIAMAKROM with borehole number 0703D4/A/042-BH11, determine the
Transmissivity of the aquifer with the Cooper-Jacob straight line solution and the Specific capacity of
the well. The transmissivity must be determined for both the discharge and recovery periods.

CONSTANT RATE TEST PUMPING FORM - SHEET

Borehole No.: Operator:
Local ID No.: BHCOE11 Locality: College of Engineering
DISTANCE 1 Well Site Geologist
Date: Engineer's Representative:
Discharge Rate: 36.00 m3/day Pump Inlet Depth below M. Point: 47.00 m
Pump Diameter: 254 mm SWL below/ above Measuring Point: 8.74 m
Observation Borehole Measuring Point above Ground Level: 0.70 m
Actual time Time Water level Drawdown
Hr Mins (mins) (cm) (meters)
7.55 0:00 0 8.74 2.43
1 11.17 2.94
2 11.68 3.45
3 12.19 3.81
4 12.55 4.04
5 12.78 4.22
6 12.96 5.06
7 13.80 4.41
8 13.15 4.49
9 13.230 4.52
10 13.26 4.65
15 13.39 4.81
20 13.55 4.86
25 13.60 5.11
30 13.85 5.15
35 13.89 5.17
40 13.91 5.22
45 13.96 5.27
50 14.01 5.38
55 14.12 5.68
60 14.42 5.79
75 14.53 5.84
90 14.58 5.88
105 14.62 5.95
120 14.69 6.05
135 14.79 6.11
150 14.85 6.15
165 14.89 6.09
180 14.83 5.97
195 14.71 5.96
210 14.70 5.95
225 14.69 5.95
240 14.69 5.97
255 14.71 5.99
270 14.73 6.01
285 14.75 6.03
300 14.77 6.08

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 315 14.82 6.11
330 14.85 6.14
345 14.88 6.17
360 14.91 2.43

From the pumping data test graph above:

Δ S = 1.4, Δ log(t) = 1, 𝑡𝑜 = 0.012
2.303𝑄
Transmissivity, T = 4𝜋Δ S Δ log(t)
(2.303)(36)
⁖T= (1) = 4.713𝑚2 /𝑑𝑎𝑦
(4𝜋)(1.4)

0.012
2.25(4.713)×( )
Specific storage, S = (1)2
24×60
= 8.837 × 10−5

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CONSTANT RATE RECOVERY FORM _______

Contract No.: Contractor:

Site
ID: Locality:
Local ID: Well Site Geologist
Engineer's
Date: Representative:
Pump Inlet Depth
ischarge below Measuring
Rate: 36.00 m3/day Point: 38.00m
Pump SWL below/ above
Diameter: mm Measuring Point: 8.74 8.74
Observation Measuring Point
hole above Ground Level: 0.70m
Time
since Time since Water Recovery Residual
Actual Time Comments
Pumping pumping level drawdown
Stopped Started t/t'
hr min (mins - t') (mins - t) (m) (m) (m)
11.02 Start of
AM 0 360 14.91 0.00 6.17 Recovery
1 361 361.000 12.73 2.18 3.99 Observation

2 362 181.000 11.45 3.46 2.71

3 363 121.000 10.80 4.11 2.06
4 364 91.000 10.45 4.46 1.71
5 365 73.000 10.18 4.73 1.44
6 366 61.000 9.97 4.94 1.23
7 367 52.429 9.85 5.06 1.11
8 368 46.000 9.75 5.16 1.01
9 369 41.000 9.69 5.22 0.95
10 370 37.000 9.64 5.27 0.90
15 375 25.000 9.54 5.37 0.80
20 380 19.000 9.54 5.37 0.80
25 385 15.400 9.52 5.39 0.78
30 390 13.000 9.50 5.41 0.76
35 395 11.286 9.48 5.43 0.74
40 400 10.000 9.46 5.45 0.72
45 405 9.000 9.44 5.47 0.70
50 410 8.200 9.43 5.48 0.69
55 415 7.545 9.42 5.49 0.68
60 420 7.000 9.41 5.50 0.67
75 435 5.800 9.40 5.51 0.66
90 450 5.000 9.37 5.54 0.63
105 465 4.429 9.34 5.57 0.60
120 480 4.000 9.31 5.60 0.57
135 495 3.67 9.280 5.63 0.54
150 510 3.400 9.25 5.66 0.51
165 525 3.182 9.220 5.69 0.48
180 540 3.000 9.16 5.75 0.42

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From the recovery data test graph above:

𝑡
Δ S ′ = 1.40, Δ log (𝑡 ′ ) = 1

2.303𝑄 𝑡
Transmissivity, T = 4𝜋ΔS′ Δ log(𝑡 ′ )

(2.303)(36)
⁖T= (1) = 4.713𝑚2 /𝑑𝑎𝑦
(4𝜋)(1.4)

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