Borehole Yield and Quality Testing at Checkers Constantia ... · one borehole at Checkers...

Borehole Yield and Quality Testing at Checkers Constantia, Cape Town.

REPORT: GEOSS Report No: 2019/01-29

PREPARED FOR:

Cameron Houston GBI Landscape Consultants

Unit D5, New Mill Road, Pinelands Business Park,

Pinelands, 7405 [email protected]

PREPARED BY: Reuben Lazarus

GEOSS - Geohydrological and Spatial Solutions International (Pty) Ltd

Unit 12, Technostell Building, 9 Quantum Street,

Technopark Stellenbosch 7600

Tel: (021) 880-1079 Email: [email protected]

(www.geoss.co.za)

06 February 2019

mailto:[email protected]

http://www.geoss.co.za/


GEOSS Report No. 2019/01-29 06 February 2019

EXECUTIVE SUMMARY

GEOSS – Geohydrological and Spatial Solutions International (Pty) Ltd – was appointed by

Cameron Houston of GBI Landscape Consultants to conduct yield and water quality testing of

one borehole at Checkers Constantia, Cape Town.

The yield testing was undertaken by GEOSS during January 2019. It is recommended to start

groundwater abstraction with the below mentioned parameters. As the yield testing was only

conducted for a 48 hour period, it cannot determine long term cumulative impacts of abstraction

from this borehole. This will need to be managed through long term monitoring data. Based on

this information the abstraction volumes can be optimised by adjusting the abstraction duration or

rate. Aquifer over-abstraction is unlikely to occur if these rates are adhered to or if the borehole is

not managed through long term monitoring data.

Borehole Details

Borehole Name Latitude

(DD)

Longitude

(DD)

Borehole

Depth (m)

Inner Diameter at

pump depth (mm)

CC_BH01 -34.029441° 18.445084° 54 142mm

Abstraction Details

Borehole Name Abstraction rate

(L/s)

Abstraction

Duration (hrs)

Recovery

Duration (hrs)

Possible Volume

Abstracted (L/d)

CC_BH01 0.50 12 12 21 600

Pump Installation Details

Borehole Name

Pump

Installation

Depth (mbgl)

Critical Water

Level (mbgl)

Dynamic

Water Level

(mbgl)*

Rest Water Level

(mbgl)

CC_BH01 25 23 21 13.66

* Typical water level expected during pumping

A water sample was collected at the end of the yield test and submitted for inorganic analysis. From

the results, the groundwater from this borehole is of a generally good quality in terms of dissolved

mineral concentrations, but has high nitrate and metal concentrations rendering it unsuitable for

consumption without prior treatment. Total coliforms were elevated but no faecal coliforms were

detected.

To facilitate monitoring and informed management of a borehole, it is highly recommended that a

borehole be equipped with the following monitoring infrastructure and equipment:

• Installation of a 32 mm (inner diameter, class 10) observation pipe from the pump depth

to the surface, closed at the bottom and slotted for the bottom 5 – 10 m. This allows for a

‘window’ of access down the borehole which enables manual water level monitoring and

can house an electronic water level logger

• Installation of an electronic water level logger (for automated water level monitoring)

• Installation of a sampling tap (to monitor water quality)

• Installation of a flow volume meter (to monitor abstraction rates and volumes)

The legal compliance with regard to the use of the groundwater also needs to be addressed with

the Department of Water and Sanitation.


GEOSS Report No. 2019/01-29 06 February 2019 i

TABLE OF CONTENTS

1. INTRODUCTION ....................................................................................................... 1

2. YIELD TESTING ........................................................................................................ 2 2.1 Methodology ............................................................................................................................... 2

2.2 Yield Testing at CC_BH01 ....................................................................................................... 2

3. WATER QUALITY ANALYSIS .................................................................................. 4

4. RECOMMENDATIONS ............................................................................................ 11

5. REFERENCES ........................................................................................................... 12

6. APPENDIX A: YIELD TEST DATA ......................................................................... 13

7. APPENDIX B: WATER QUALITY ANALYSIS ....................................................... 18

8. APPENDIX C: MONITORING INFRASTRUCTURE DIAGRAM ........................ 21

LIST OF FIGURES Figure 1: Borehole Locality Map ............................................................................................................... 1 Figure 2: Step Test drawdown data for CC_BH01. ................................................................................ 3 Figure 3: Time-series drawdown for CC_BH01. .................................................................................... 3 Figure 4: Water level recovery graph after the CDT (CC_BH01) ........................................................ 4 Figure 5: Piper diagram of the production borehole groundwater sample. ........................................ 8 Figure 6: Stiff diagram of the borehole groundwater sample. .............................................................. 9 Figure 7: SAR diagram of the borehole groundwater sample. ........................................................... 10

LIST OF TABLES Table 1: Borehole Details ........................................................................................................................... 1 Table 2: Yield Determination - CC_BH01............................................................................................... 4 Table 3: Classification table for specific limits......................................................................................... 5 Table 4: Production borehole results classified according the SANS241-1:2015 ............................... 5 Table 5: Classification table for the groundwater results (DWAF, 1998) ........................................... 6 Table 6: Classified production borehole results according to DWAF 1998. ...................................... 7 Table 7: Borehole Abstraction Recommendations ............................................................................... 11


GEOSS Report No. 2019/01-29 06 February 2019 ii

ABBREVIATIONS bh borehole CDT constant discharge test Drawdown meters below rest water level DWA Department of Water Affairs (2010 - 2014) DWAF Department of Water Affairs and Forestry (pre- 2010) DWS Department of Water and Sanitation (2014 - current) ha hectare ID inner diameter L/s litres per second m metres mamsl metres above mean sea level MAP Mean Annual Precipitation mbch metres below collar height mbgl metres below ground level RWL rest water level below ground level WGS84 Since the 1st January 1999, the official co-ordinate system for South Africa is based on the World Geodetic System 1984 ellipsoid, commonly known as WGS84.

Suggested reference for this report: GEOSS (2019). Borehole Yield and Quality at Checkers Constantia, Cape Town. GEOSS Report Number: 2018/01-29. GEOSS - Geohydrological & Spatial Solutions International (Pty) Ltd. Stellenbosch, South Africa.

Cover photo: Site photo during yield testing GEOSS project number:

2017_03-2049 Reviewed by: Dale Barrow (06 February 2019).


GEOSS Report No. 2019/01-29 06 February 2019 1

1. INTRODUCTION

GEOSS – Geohydrological and Spatial Solutions International (Pty) Ltd – was appointed by

Cameron Houston of GBI Landscape Consultants to conduct yield and water quality testing of

one borehole at Checkers Constantia, Cape Town.

The borehole (CC_BH01), was tested by GEOSS during January 2019, details of this are presented

in this report. The borehole details are presented in Table 1 below and spatially in Figure 1.

Table 1: Borehole Details

Borehole Latitude Longitude Depth (m)

CC_BH01 -34.029441° 18.445084° 54

Figure 1: Borehole Locality Map



2. YIELD TESTING

2.1 Methodology

The yield testing was undertaken by GEOSS during January 2019 and carried out according to the

National Standard (SANS 10299-4:2003, Part 4 – Test pumping of water boreholes). This included

a Step Test, Constant Discharge Test and recovery monitoring. For the Step Test, the borehole is

pumped at a constant rate for one-hour intervals (steps) and the flow rates are incrementally

increased for each step. This test is followed by a Constant Discharge Test (CDT) where the

borehole is pumped at a constant rate for an extended period of time, followed by recovery

monitoring. The water level drawdown is monitored at pre-determined intervals during these tests

(drawdown refers to the difference in water level from the rest water level (RWL) measured before

commencement of the yield test). All raw data and measurements taken during the actual yield test

are presented in Appendix A.

The yield test data was analysed using the FC Software developed by the IGS (Institute for

Groundwater Studies) in Bloemfontein. This method evaluates fractal pumping tests and well

performance, and makes use of derivatives, boundary information and error propagation to

evaluate the sustainable yield of a borehole. A water sample was collected at the end of the yield

test and submitted for inorganic chemical analysis.

2.2 Yield Testing at CC_BH01

The yield testing was conducted between the 21th and the 24th of January 2019. The borehole was

measured at a depth of 54 meters before the start of the test. The test pump was installed at a depth

of 46 meters below ground level (mbgl). The RWL at the start of the test was 13.66 mbgl.

During the Step Test, the water level was drawn down 31.5 meters below the rest water level (45

mbgl) at the end of the 3rd step rate of 1.0 L/s. Figure 2 shows the time-series drawdown for the

Step Test.



Figure 2: Step Test drawdown data for CC_BH01.

Based on the results of the Step Test, the CDT was conducted at a rate of 0.5 L/s. At the end of

the 48-hour period, the water level had drawn down 10 meters below the rest water level (23.66

mbgl). The semi-log plot of the drawdown is presented in Figure 3.

Figure 3: Time-series drawdown for CC_BH01.

The recovery of the water level was monitored after the CDT and is presented in Figure 4. The

recovery of the water level is good, attaining 96% recovery after approximately 80 minutes.



Figure 4: Water level recovery graph after the CDT (CC_BH01)

Several methods were used to assess the yield test data as presented in Table 2. It is recommended

that the borehole is initially pumped a rate of 0.50 L/s for 12 hours per day followed by an 12 hour

recovery period.

Table 2: Yield Determination - CC_BH01

CC_BH01

Method Sustainable Yield (L/s)

Late T (m2/d)

AD used

Basic FC 0.3 7.2 8.5

FC inflection point 0.3 0.0 9

Cooper-Jacob 0.3 10.4 8.5

FC Non-Linear 0.3 8.0 8.5

Average Q_sust (L/s) 0.3

Recommended Abstraction

Abstraction Rate (L/s) Abstraction Duration (hours) Recovery Duration (hours)

0.50 12 12

3. WATER QUALITY ANALYSIS

A groundwater sample was collected at the end of the yield test and submitted for inorganic

microbiological chemical analysis to a SANAS accredited laboratory (Bemlab) in the Western Cape.

The certificate of analysis for the sample is presented in Appendix B.

The chemistry results obtained have been classified according to the SANS241-1: 2015 standards

for domestic water. Table 3 enables an evaluation of the water quality with regards to the various

limits.



Table 4 presents the water chemistry analysis results, colour coded according to the SANS241-1:

2015 drinking water assessment standards.

Table 3: Classification table for specific limits

Acute Health Aesthetic Chronic health Operational Acceptable

Table 4: Production borehole results classified according the SANS241-1:2015

Analyses CC_BH01 SANS 241-1:2015

pH (at 25 ºC) 4.6 ≥5 - ≤9.7 Operational

Conductivity (mS/m) (at 25 ºC) 72.0 ≤170 Aesthetic

Total Dissolved Solids (mg/L) 462.0 ≤1200 Aesthetic

Turbidity (NTU) 0.39 ≤5 Aesthetic ≤1 Operational

Colour (mg/L as Pt) 2.0 ≤15 Aesthetic

Sodium (mg/L as Na) 56.2 ≤200 Aesthetic

Potassium (mg/L as K) 6.9 N/A

Magnesium (mg/L as Mg) 28.3 N/A

Calcium (mg/L as Ca) 20.6 N/A

Chloride (mg/L as Cl) 147.0 ≤300 Aesthetic

Sulphate (mg/L as SO4) 59.00 ≤250 Aesthetic ≤500 Acute Health

Nitrate & Nitrite Nitrogen (mg/L as N) 15.85 ≤12 Acute Health

Nitrate Nitrogen (mg/L as N) 15.83 ≤11 Acute Health

Nitrite Nitrogen (mg/L as N) 0.02 ≤0.9 Acute Health

Ammonia Nitrogen (mg/L as N) <0.28 ≤1.5 Aesthetic

Total Alkalinity (mg/L as CaCO3) <11.49 N/A

Total Hardness (mg/L as CaCO3) 167.53 N/A

Fluoride (mg/L as F) 0.1 ≤1.5 Chronic Health

Aluminium (mg/L as Al) 1.4633 ≤0.3 Operational

Vanadium (mg/L as V) 0.00000 N/A

Total Chromium (mg/L as Cr) <0.027 ≤0.05 Chronic Health

Manganese (mg/L as Mn) 0.20 ≤0.1 Aesthetic ≤0.4 Chronic Health

Iron (mg/L as Fe) 0.1 ≤0.3 Aesthetic ≤2 Chronic Health

Cobalt (mg/L as Co) N/A

Nickel (mg/L as Ni) 0.0060 ≤0.07 Chronic Health

Copper (mg/L as Cu) <0.02 ≤2 Chronic Health

Zinc (mg/L as Zn) <0.03 ≤5 Aesthetic

Arsenic (mg/L as As) <0.005 ≤0.01 Chronic Health

Selenium (mg/L as Se) <0.012 ≤0.04 Chronic Health

Cadmium (mg/L as Cd) <0.0031 ≤0.003 Chronic Health

Antimony (mg/L as Sb) <0.002 ≤0.02 Chronic Health

Mercury (mg/L as Hg) <0.0031 ≤0.006 Chronic Health

Lead (mg/L as Pb) <0.007 ≤0.01 Chronic Health

Uranium (mg/L as U) ≤0.03 Chronic Health

Cyanide (mg/L as CN-) 0.0040 ≤0.2 Acute Health

Total Organic Carbon (mg/L as C) 6.90 N/A

E.coli (count per 100 ml) <1 Not Det. Acute Health-1

Total Coliform Bacteria (count per 100 ml) <1 Not Det.≤10 Operational

Heterotrophic Plate Count (count per ml) 17100.0 ≤1000 Operational

The chemistry results obtained have been classified according to the DWAF (1998) standards for

domestic water. Table 5 enables an evaluation of the water quality with regards to the various

parameters measured (DWAF, 1998). Table 6 presents the water chemistry analysis results colour

coded according to the DWAF drinking water assessment standards.



Table 5: Classification table for the groundwater results (DWAF, 1998) Blue (Class 0) Ideal water quality - suitable for lifetime use.

Green (Class I) Good water quality - suitable for use, rare instances of negative effects.

Yellow (Class II) Marginal water quality - conditionally acceptable. Negative effects may occur.

Red (Class III) Poor water quality - unsuitable for use without treatment. Chronic effects may occur.

Purple (Class IV) Dangerous water quality - totally unsuitable for use. Acute effects may occur.



Table 6: Classified production borehole results according to DWAF 1998.

Sample Marked : CC_BH01 DWA (1998) Drinking Water Assessment Guide

Class 0 Class I Class II Class III Class IV

pH 4.6 5-9.5 4.5-5 & 9.5-10 4-4.5 & 10-10.5 3-4 & 10.5-11 < 3 & >11

Conductivity (mS/m) 72.0 <70 70-150 150-370 370-520 >520

Turbidity (NTU) 0.39 <0.1 0.1-1 1.0-20 20-50 >50

mg/L

Total Dissolved Solids 462.0 <450 450-1000 1000-2400 2400-3400 >3400

Sodium (as Na) 56.2 <100 100-200 200-400 400-1000 >1000

Potassium (as K) 6.9 <25 25-50 50-100 100-500 >500

Magnesium (as Mg) 28.3 <70 70-100 100-200 200-400 >400

Calcium (as Ca) 20.6 <80 80-150 150-300 >300

Chloride (as Cl) 147.0 <100 100-200 200-600 600-1200 >1200

Sulphate (as SO4) 59.0 <200 200-400 400-600 600-1000 >1000

Nitrate& Nitrite (as N) 15.85 <6 6.0-10 10.0-20 20-40 >40

Fluoride (as F) 0.1 <0.7 0.7-1.0 1.0-1.5 1.5-3.5 >3.5

Manganese (as Mn) 0.20 <0.1 0.1-0.4 0.4-4 4.0-10.0 >10

Iron (as Fe) 0.1 <0.5 0.5-1.0 1.0-5.0 5.0-10.0 >10

Copper (as Cu) <0.02 <1 1-1.3 1.3-2 2.0-15 >15

Zinc (as Zn) <0.03 <20 >20

Arsenic (as As) <0.005 <0.010 0.01-0.05 0.05-0.2 0.2-2.0 >2.0

Cadmium (as Cd) <0.0031 <0.003 0.003-0.005 0.005-0.020 0.020-0.050 >0.050

Hardness (as CaCO3) 167.53 <200 200-300 300-600 >600 counts/100 mL

Faecal coliforms <1 0 0-1 1.0-10 10-100 >100

Total coliforms <1 0 0-10 10-100 100-1000 >1000



From the chemical results presented in

Table 4 and Table 6 it is clear that the groundwater from this borehole is of a generally good

quality in terms of dissolved mineral concentrations, but has high nitrate and metal concentrations

rendering it unsuitable for consumption without prior treatment. Total coliforms were elevated but

no faecal coliforms were detected.

A number of chemical diagrams have been plotted for the groundwater sample and these are useful

for chemical characterisation of the water.

The chemistry of the sample has been plotted on a tri-linear diagram known as a Piper diagram.

This diagram indicates the distribution of cations and anions in separate triangles and then a

combination of the chemistry in the central diamond. From Figure 5 (central diamond) the

production borehole groundwater sample is classified as having a mixed hydrofacies with high

chloride concentrations.

Figure 5: Piper diagram of the production borehole groundwater sample.

The Stiff Diagram is a graphical representation of the relative concentrations of the cations

(positive ions) and anions (negative ions). This diagram shows concentrations of cations and anions

relative to each other (not as a percentage as with Piper) and direct reference can be made to

specific salts in the water. The Stiff Diagram for the sample from the borehole is shown in Figure

CC_BH01



6. It is clear that the groundwater sample collected is dominated by Sodium & Potassium/Chloride

concentrations.

Figure 6: Stiff diagram of the borehole groundwater sample.

The Sodium Adsorption Ratio (SAR) of the groundwater sample is plotted in Figure 7. The

groundwater is plotted as S1/C2, thus classified as low risk in terms of sodium adsorption and

medium risk in terms of salinity hazard. This graph is typically applicable to irrigation.



Figure 7: SAR diagram of the borehole groundwater sample.

SAR Diagram

CC_BH01



4. RECOMMENDATIONS

Based on the information obtained from the yield test, the abstraction recommendations for the

borehole are presented in Table 7. As the yield testing was only conducted for a 48 hour period,

it cannot determine long term cumulative impacts of abstraction from this borehole. This will need

to be managed through long term monitoring data.

Table 7: Borehole Abstraction Recommendations

Borehole Details

Borehole

Name

Latitude

(DD)

Longitude

(DD)

Borehole

Depth (m)

Inner Diameter at

pump depth (mm)

CC_BH01 -34.029441° 18.445084° 54 142

Abstraction Details

Borehole

Name

Abstraction rate

(L/s)

Abstraction

Duration (hrs)

Recovery

Duration (hrs)

Possible Volume

Abstracted (L/d)

CC_BH01 0.50 12 12 21 600

Pump Installation Details

Borehole

Name

Pump

Installation

Depth (mbgl)

Critical Water

Level (mbgl)

Dynamic

Water Level

(mbgl)*

Rest Water Level

(mbgl)

CC_BH01 25 23 21 13.66

It is recommended that the borehole (CC_BH01) is initially pumped a rate of 0.50 L/s for 12 hours

followed by an 12 hour recovery period. A recovery period is essential to allow for the fracture

network suppling the borehole to be replenished. The pump can be installed at a depth of 25 meters

below ground level. It is anticipated that abstraction at the recommended rates will cause the water

level to drop to a depth of approximately 21 mbgl – this is referred to as the dynamic water level.

During abstraction, the water level should not drop below 23 mbgl, calculated from the available

drawdown and the reaction of the aquifer during the CDT.

Through long term water level monitoring data, the abstraction volumes can be optimised by

adjusting the abstraction duration and rate. It is therefore recommended that the borehole is

equipped with a pump operating of a timer switch and variable speed drive so that adjustments can

be easily made.

From the laboratory results, the groundwater from this borehole is of a generally good quality in

terms of dissolved mineral concentrations, but has high nitrate and metal concentrations rendering

it unsuitable for consumption without prior treatment. Total coliforms were elevated but no faecal

coliforms were detected.

As of January 2018 the Department of Water and Sanitation released a Government Gazette stating

that: “All water use sector groups and individuals taking water from any water resource (surface or

groundwater) regardless of the authorization type, in the Berg, Olifants and Breede Gouritz Water

Management Area, shall install electronic water recording, monitoring or measuring devices to

enable monitoring of abstractions, storage and use of water by existing lawful users and establish

links with any monitoring or management system as well as keep records of the water used.”



Therefore, to facilitate monitoring and informed management of a borehole, it is highly

recommended that a borehole be equipped with the following monitoring infrastructure and

equipment (diagram included in Appendix C):

• Installation of a 32 mm (inner diameter, class 10) observation pipe from the pump depth

to the surface, closed at the bottom and slotted for the bottom 5 – 10 m. This allows for a

‘window’ of access down the borehole which enables manual water level monitoring and

can house an electronic water level logger

• Installation of an electronic water level logger (for automated water level monitoring)

• Installation of a sampling tap (to monitor water quality)

• Installation of a flow volume meter (to monitor abstraction rates and volumes)

This data should be analysed by a qualified Hydrogeologist to ensure long term sustainable use

from the borehole. The legal compliance with regard to the use of the groundwater also needs to

be addressed with the Department of Water and Sanitation.

5. REFERENCES

DWAF (1998). Quality of domestic water supplies, Volume 1: Assessment guide. Department of

Water Affairs and Forestry, Department of Health, Water Research Commission, 1998.

National Water Act (1998). The National Water Act, No 36. Department of Water Affair and

Forestry. Pretoria.

SANS (10299-4:2003). South African National Standard. Development, maintenance and

management of groundwater resources. Part 4: Test-pumping of water boreholes. ISBN 0-

626-14912-6.

SANS (241-1:2015). Drinking water – Part 1: Microbiological, physical, aesthetic and chemical

determinants.



6. APPENDIX A: YIELD TEST DATA



Province

Area

Farm/Site Name

Observer Date Step no Length Comments

Pump type 21-Jan-19 1 1 hr 0.3 L/s Completed

-34.029441 Lat 21-Jan-19 2 1 hr 0.5 L/s Completed

18.445084 Long 21-Jan-19 3 1 hr 1.0 L/s Completed

BoreholeStatus

Borehole depth (Before test) 53.7 m

Borehole depth (After test) 53.7 m

Borehole diameter (OD,ID) OD 160mm ID 142mm mm

Dummy pump test x4

Casing depth m Length (h) Comments

Casing height 0.16 m 48 0.5 l/s Completed

Datum level above ground 0.58 m

Test pump depth 50 m

Observation pipe depth 45.63 m

Logger depth 45.63 m

Available Drawdown 32.55 m

13.66 mbch

13.08 mbgl

Outlet distance Borehole: Data:

Water sample taken & type

Rest water level before test

Constantia

Checkers Constantia

Co-ordinates

unequipped

Manuel/Nunens

Test dateSite Details

Borehole Name CC_BH01

21-Jan-19 -Western Cape 24-Jan-19

Project Name GBI_Shoprite_Groundwater

Project Number 2049_L

Borehole Yield Test Results

Step test details

Start Date

Flow rate (set)

Constant discharge test details

Flow rate (set)

22-Jan-19

Monitoring boreholes

Recovery details

Start Date Data Capture

Solinst logger24-Jan-19

Distance from: CC_BH01

Comments:

SANS241 inorganic & micro

100 m

completed



Step Test 2049_L CC_BH01

0.3 l/s 0.5 l/s

Time interval (min)Water level drawdown

(m)Time interval (min)

Water level drawdown

(m)

0 0.000 65 3.619

5 2.070 70 3.259

10 3.513 75 3.255

15 1.895 80 3.267

20 1.756 85 3.276

25 1.755 90 3.291

30 1.763 95 3.297

35 1.823 100 3.309

40 1.799 105 3.309

45 1.805 110 3.323

50 1.809 115 3.328

55 1.830 120 3.338

60 1.841

1 l/s 0 l/s

125 5.244

130 9.424

135 13.027

140 16.891

145 19.880

150 22.444

155 25.042

160 27.026

165 29.361

170 31.425

175 31.420

Step 1 Step 2

21-Jan-19

GBI_Shoprite_Groundwater

Step 3 Step 4



0.5 L/s

HoursTime interval

(min)

Water level

drawdown (m)Hours

Time interval

(min)

Water level

drawdown (m)

0 0.000 20 1320 8.208

1 24 1440 8.285

2 26 1560 7.876

3 28 1680 8.350

4 30 1800 8.190

5 3.903 32 1920 8.308

6 34 2040 8.334

7 36 2160 8.393

8 38 2280 8.310

9 40 2400 8.383

10 6.759 42 2520 8.358

12 44 2640 8.081

15 5.426 46 2760 9.106

20 5.100 48 2880 10.055

25 4.900

30 4.181

40 3.753

50 3.801

1 60 4.360

70 4.722

80 4.569

90 4.726

100 4.724

2 120 4.769

150 4.822

3 180 4.897

4 240 4.747

5 300 4.763

6 360 4.963

8 480 5.408

10 600 5.984

12 720 6.435

14 840 6.782

16 960 7.340

18 1080 7.569

20 1200 7.915

Abstraction rate

Test Duration: 48 hours

Constant Discharge Test (CDT) - Raw data


2049_L CC_BH01 22-Jan-19



2049_L CC_BH01 24-Jan-19

Hours Time interval (min) Water level drawdown (m)

0 7.504

1

2

3

4

5

6

7

8

9

10 0.562

12

15 0.566

20 0.540

25 0.518

30 0.500

40 0.466

50 0.435

1 60 0.414

70 0.399

80 0.374

Post CDT Recovery




7. APPENDIX B: WATER QUALITY ANALYSIS



8. APPENDIX C: MONITORING INFRASTRUCTURE DIAGRAM



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