Borehole Yield and Quality Testing at Croydon Vineyard Estate, Somerset West. Western ...croydonvineyardestate.com/wp-content/uploads/GEOSS... · · 2017-12-10Borehole Yield and

Borehole Yield and Quality Testing at Croydon Vineyard Estate, Somerset West.

Western Cape.

REPORT: GEOSS Report No: 2017/12-13

PREPARED FOR: Tobie Esterhuyzen

Estate Manager Croydon Vineyard Estate c/o R102 & Kramat Rd

Somerset West

PREPARED BY: Cameron Brand

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 December 2017

mailto:[email protected]

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

Borehole Yield and Quality Testing at Croydon Vineyard Estate, Somerset West. Western Cape.

GEOSS Report No. 2017/12-13 06 December 2017

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

by Tobie Esterhuyzen of Croydon Vineyard Estate, to conduct yield and quality testing of

two boreholes at Croydon Vineyard Estate near Somerset West, Western Cape.

The boreholes on this property were drilled some time ago and are currently equipped with

submersible borehole pumps which supply the estate with water. The yield testing was

undertaken by GEOSS during the month of November 2017. The abstraction

recommendations for the boreholes tested are presented in the table below:

Site Pump depth (mbgl)

Yield (L/s)

Abstraction duration (hours)

Rest duration (hours)

Maximum water level

(mbgl)

Possible volume abstracted per

day (Litres)

CE_BH01 80 0.2 2 10 75 2,880

CE_BH02 18 1.5 10 14 10 54,000

A water sample was collected at the end of the test and submitted for inorganic chemical

analysis. From the results it is clear that the groundwater from this borehole is good in

terms of dissolved mineral concentrations. The level of chloride is slightly elevated and

treatment may be required depending on the intended use.

It is suggested that long term borehole water level monitoring is conducted. Monitoring

can be done automatically using a water level logger, or done manually. The monitoring

should be done at least on a monthly basis. A rest water level can be manually taken using a

dip meter, along with a flow meter measurement. To facilitate monitoring and informed

management of the borehole, it is recommended that the borehole be equipped with

monitoring infrastructure:

Installation of a 40 mm OD (class 10) observation pipe from the pump depth to

the surface, closed at the bottom and slotted for the bottom 5 – 10 m. This enables

manual or automated water level monitoring.

Installation of a sampling tap.

Installation of a flow volume meter.

Correct registration / licensing procedures must be followed as required by the

Department of Water Affairs prior to use of the groundwater.

Ooo oOo ooO


GEOSS Report No. 2017/12-13 06 December 2017 i

TABLE OF CONTENTS

1. INTRODUCTION ............................................................................................... 3

2. METHODOLOGY ............................................................................................... 4

3. YIELD TESTING ................................................................................................. 4 3.1 CE_BH01 ............................................................................................................................ 4

3.2 CE_BH02 ............................................................................................................................ 8

4. WATER QUALITY ANALYSIS .......................................................................... 12

5. RECOMMENDATIONS .................................................................................... 13

6. REFRENCES ....................................................................................................... 14

7. APPENDIX A: YIELD TEST DATA .................................................................. 15

8. APPENDIX B: WATER QUALITY ANALYSIS ................................................ 27

LIST OF FIGURES Figure 1: Borehole Positions ........................................................................................................... 3 Figure 2: Step Test drawdown data for CE_BH01. ..................................................................... 5 Figure 3: Time vs Drawdown of CE_BH01 (CDT (first) at 0.2 L/s) ....................................... 5 Figure 4: Time vs Drawdown of CE_BH01 (CDT (second) at 0.2 L/s) .................................. 6 Figure 5: Log - log plot of the time-series drawdown and derivatives during the CDT

(CE_BH01) (0.2 L/s) ............................................................................................................. 7 Figure 6: Water level recovery graph after the second CDT (CE_BH01) ................................ 7 Figure 7: Step Test drawdown data for CE_BH02. ..................................................................... 8 Figure 8: Drawdown vs Time for CE_BH02 (CDT (first) at 2.0 L/s) ..................................... 9 Figure 9: Log - log plot of the time-series drawdown and derivatives during the CDT

(CE_BH02) (2.0 L/s) ............................................................................................................. 9 Figure 10: Time-series drawdown CE_BH02 (CDT(second) at 1.5 L/s) ............................... 10 Figure 11: Log - log plot of the time-series drawdown and derivatives during the CDT

(CE_BH02) (1.5 L/s) ........................................................................................................... 11 Figure 12: Water level recovery graph after the CDT (CE_BH02) ......................................... 11

LIST OF TABLES Table 1: Borehole Details ................................................................................................................. 3 Table 2: CE_BH02 – Yield Determination ................................................................................. 12 Table 3: Borehole Abstraction Recommendations .................................................................... 13


GEOSS Report No. 2017/12-13 06 December 2017 ii

ABBREVIATIONS 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 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 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 (2017). Borehole Yield and Quality Testing at Croydon Vineyard Estate, Somerset West. Western Cape. GEOSS Report Number: 2017/12-13. GEOSS - Geohydrological & Spatial Solutions International (Pty) Ltd. Stellenbosch, South Africa.

Cover photo: CE_BH02 GEOSS project number:

2017_10-2481 Review: Julian Conrad (6 December 2017).


GEOSS Report No. 2017/12-13 06 December 2017 3

1. INTRODUCTION

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

by Tobie Esterhuyzen of Croydon Vineyard Estate, to conduct yield and quality testing of

two boreholes at Croydon Vineyard Estate near Somerset West, Western Cape. The

boreholes on this property were drilled some time ago, drilling information and was not

made known to GEOSS. Both boreholes are currently equipped with submersible borehole

pumps which supply the estate with water. The borehole details are presented in Table 1

below, and spatially in Figure 1.

Table 1: Borehole Details

Site Latitude Longitude Depth (m)

CE_BH01 -34.036720° 18.750470° 83.2

CE_BH02 -34.043130° 18.751180° 19.13

Figure 1: Borehole Positions



2. METHODOLOGY

The yield testing was undertaken by GEOSS 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 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 is 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.

3. YIELD TESTING

3.1 CE_BH01

The yield testing of CE_BH01 was conducted between the 27th and the 30th of November

2017. The existing pump is installed at a depth of 66 meters - this pump was removed for

the yield test and reinstalled after the test was completed. The borehole was measured at a

depth of 83.2 meters. The test pump was initially installed at a similar depth to the existing

pump but then lowered to the bottom of the borehole for the second Constant Discharge

Test (CDT). The rest water level (RWL) at the start of the test was 0.99 meters below

ground level.

During the Step Test, the water level was drawn down to the pump inlet during the second

step conducted at a rate of 0.5 L/second. Figure 7 shows the time-series drawdown for

the Step Test.



Figure 2: Step Test drawdown data for CE_BH01.

Based on the results of the Step Test, the Constant Discharge Test (CDT) was conducted

at a rate of 0.2 L/second. A CDT was initially conducted with the pump installed at a

depth of 60 meters: Once the water bearing fracture zone at approximately 10 meters

below ground level is dewatered, there is a steady but rapid decrease in the water level –

causing the water level to be drawn down to the pump after approximately 2.5 hours of

pumping. The drawdown for the first CDT is presented in Figure 3.

Figure 3: Time vs Drawdown of CE_BH01 (CDT (first) at 0.2 L/s)

Dewatering of water

bearing fracture zone

Dewatering of water




Once the water level had recovered, the test pump was lowered to the bottom of the

borehole. A second CDT was then conducted at the same rate (0.2 L/second). This caused

the water level to be drawn down to the pump after 3.25 hours of pumping, following a

similar trend to the first CDT. The drawdown for the second CDT is presented in Figure

4.

Figure 4: Time vs Drawdown of CE_BH01 (CDT (second) at 0.2 L/s)

The log-log plot of the drawdown with time for the second CDT is shown in Figure 5.

The derivative plots are useful for indicating where changes in the rate of drawdown occur.

An increase in the rate of drawdown is visible after approximately 30 minutes of pumping

as the water bearing fracture zone is dewatered (indicated by the increased downward slope

of the first derivative).

Dewatering of water




Figure 5: Log - log plot of the time-series drawdown and derivatives during the CDT

(CE_BH01) (0.2 L/s)

The recovery of the water level was monitored after the CDT and is presented in Figure 6.

The recovery of the water level is moderate; attaining 95 % recovery in approximately 11

hours.

Figure 6: Water level recovery graph after the second CDT (CE_BH01)

It is recommended that the borehole is pumped a rate of 0.2 L/second for 2 hours per day

followed by a 10 hour recovery period.



3.2 CE_BH02

The yield testing at CE_BH02 was conducted between the 22nd and the 27th of November

2017. The existing pump is installed at a depth of 18.85 meters below ground level - this

pump was removed for the yield test and reinstalled after the test was completed. The

borehole was measured at a depth of 19.13 meters. The test pump was installed at a depth

of 18.5 meters below ground level. The rest water level (RWL) at the start of the test was

2.5 meters below ground level. During the Step Test, the water level was drawn down to

the pump inlet during the 5th step conducted at a rate of 3.5 L/second. Figure 7 shows the

time-series drawdown for the Step Test.

Figure 7: Step Test drawdown data for CE_BH02.

Based on the results of the Step Test, the Constant Discharge Test (CDT) was conducted

at a rate of 2.0 L/second. Once the water bearing fracture zone (approximately 10 meters

below ground level) is dewatered, there is rapid increase in the rate of water level

drawdown – causing the water level to be drawn down to the pump after approximately 10

hours of pumping. The semi-log plot of the drawdown is presented in Figure 8.

Dewatering of water




Figure 8: Drawdown vs Time for CE_BH02 (CDT (first) at 2.0 L/s)

The log-log plot of the drawdown with time for the CDT is shown in Figure 9. The

derivative plots are useful for indicating where changes in the rate of drawdown occur. A

increase in the rate of drawdown is visible after approximately 550 minutes of pumping as

the water bearing fracture zone is dewatered (indicated by the sudden downward slope of

the first derivative).


(CE_BH02) (2.0 L/s)

Dewatering of water


Dewatering of water




Once the water level had recovered, a second CDT was restarted at a lower rate of 1.5

L/second. The drawdown of the water level is very similar to the first CDT, remaining

stable until the dewatering of the water bearing fracture zone (approximately 10 meters

below ground level). Once the water bearing fracture zone has been dewatered, there is

rapid increase in the rate water level drawdown– causing the water level to be drawn down

to the pump after approximately 14.4 hours. The semi-log plot of the drawdown is

presented in Figure 10.

Figure 10: Time-series drawdown CE_BH02 (CDT(second) at 1.5 L/s)

The log-log plot of the drawdown with time for the CDT is shown in Figure 11. The

derivative plots are useful for indicating where changes in the rate of drawdown occur. An

increase in the rate of drawdown is visible after approximately 750 minutes of pumping as

the water bearing fracture zone is dewatered (indicated by the sudden downward slope of

the first derivative).

Dewatering of water





(CE_BH02) (1.5 L/s)

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

12. The recovery of the water level is slow; attaining 95 % recovery in approximately 50

hours.

Figure 12: Water level recovery graph after the CDT (CE_BH02)

Dewatering of water




Several methods were used to assess the yield test data and a summary is presented in

Table 2. It is recommended that the borehole is pumped a rate of 1.5 L/second for 10

hours per day followed by a 14 hour recovery period.

Table 2: CE_BH02 – Yield Determination

4. WATER QUALITY ANALYSIS

Lab results not yet received

Applicable Std. Dev S AD used

FALSE 0.13 5.22E-03 13.0

FALSE 1.00E-03 13.0

FALSE 0.00 12.0

TRUE 0.59 3.16E-06 13.0

TRUE 0.94 1.00E-05 13.0

TRUE 0.72 Kf = 222 Ss = 1.00E-07 13.0

0.34 b = 0.10 1.95

1.01

10 1.57 L/s for 10 hours per day

1.9

Hours per day of pumping

Advanced FC

Barker

Cooper-Jacob

0.00FC inflection point

1.32

13.8

32

1.9

Method

Basic FC

Early T (m2/d) Late T (m

2/d)

32

Sustainable yield (l/s)

0.23

23.0FC Non-Linear

for 24 hours per day

Fractal dimension n =

Recommended abstraction rate (L/s)

Average Q_sust (l/s) 1.01

1.06

0.65



5. RECOMMENDATIONS

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

the borehole is presented in Table 3.

Table 3: Borehole Abstraction Recommendations

Site Pump depth (mbgl)

Yield (L/s)

Abstraction duration (hours)

Rest duration (hours)

Maximum water level

(mbgl)

Possible volume abstracted per

day (Liters)

CE_BH01 80 0.2 2 10 75 2,880

CE_BH02 18 1.5 10 14 10 54,000

It is recommended that CE_BH01 is pumped at a rate of 0.2 L/second for 2 hours per day

followed by a 10 hour recovery period (twice per day if necessary – if so monitoring is

crucial). Once the water level drops below the water bearing fracture zone (approximately

10 meters below ground level), the rate of drawdown increases. Best practise is to not let

the water level be drawn down past the fracture zone. This causes a loss in the hydrostatic

pressure (within the fractures) which can cause the fractures to collapse - and in turn, can

reduce the yield from the borehole. However as this borehole is very low yielding, to

abstract the maximum volumes, the borehole will need to be pumped until the water level

is just above the pump. It is recommended that the pump is fitted with an automatic cut

off switch to prevent the water level dropping to the pump depth and causing the pump to

burn out. Through long term monitoring data the abstraction volumes can be optimised by

adjusting the pumping duration.

It is recommended that CE_BH02 is pumped at a rate of 1.5 L/second for 10 hours per

day followed by a 14 hour recovery period. The water level should not exceed 10 meters

below ground level - just above the point at which the fracture zone is dewatered. As this

borehole has limited storage it is recommended that the pumping duration is only

optimised through long term monitoring data.

Monitoring can be done automatically using a water level logger, or done manually. The

monitoring should be done at least on a monthly basis. A rest water level can be manually

taken using a dip meter, along with a flow meter measurement. To facilitate monitoring and

informed management of the borehole, it is highly recommended that the borehole be

equipped with monitoring infrastructure:

Installation of a 40 mm OD (class 10) observation pipe from the pump depth to

the surface, closed at the bottom and slotted for the bottom 5 – 10 m. This enables

manual or automated water level monitoring.

Installation of a sampling tap.

Installation of a flow volume meter.

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

addressed with the Department of Water and Sanitation



6. REFRENCES

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 241-1:2015. Drinking water – Part 1: Microbiological, physical, aesthetic and

chemical determinants.

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.



7. APPENDIX A: YIELD TEST DATA



CE_BH01

\

Province

Area

Farm/Site Name

Observer Date Step no Length Comments

Pump type 27-Nov-17 1 1 hr 0.2 L/s Complete

34.03672 Lat 27-Nov-17 2 18 min 0.5 L/s Pump inlet

19.75047 Long

BoreholeStatus

Borehole depth (Before test) 83.2 m

Borehole depth (After test) 83.2 m

Borehole diameter (OD,ID) 200, 120 mm

Dummy pump test Complete

Casing depth PVC entire m Length (h) Comments

Casing height 0.34 m 3.25 0.2 l/s Pump inlet

Datum level above ground 0.49 m

Test pump depth 80 m

Observation pipe depth 75 m

Logger depth 55.58 m

Available Drawdown 54.59 m

1.48 mbch

0.99 mbgl

Outlet distance Borehole: Data:

Water sample taken & type

Distance from: CE_BH01

Comments:

Inorganic

100 meters

Low yielding, slight obstruction at 30 meters.

29-Nov-17

Monitoring boreholes

Recovery details

Start Date Data Capture

Solinst logger29-Nov-17

Step test details

Start Date

Flow rate (set)

Constant discharge test details

Flow rate (set)

Project Name Ian_de_Jager_Croydon_Estate

Project Number 2481_A

Borehole Yield Test Results

Test dateSite Details

Borehole Name CE_BH01

27-Nov-17 -Western Cape 00-Jan-00

Rest water level before test

Somerset West

Croydon Estate

Co-ordinates

WILO QFN 25-25

Open

Maneul/Nunens



Step Test 2481_A CE_BH01

0.2 l/s 0.5 l/s

Time interval (min)Water level

drawdown (m)Time interval (min)

Water level

drawdown (m)

0.5 1.001 60.5 34.277

1 1.764 61 34.877

1.5 2.067 61.5 35.562

2 2.174 62 36.161

2.5 2.365 62.5 36.815

3 2.591 63 37.429

4 2.972 64 38.657

5 3.363 65 39.807

6 3.730 66 40.938

7 4.094 67 42.034

8 4.384 68 43.127

9 4.766 69 44.191

10 5.216 70 45.177

12 6.033 72 47.159

15 7.109 78 54.142

20 7.755 Pump inlet

25 10.477

30 13.620

40 20.309

50 26.999

60 33.580

Step 1 Step 2

27-Nov-17

Ian_de_Jager_Croydon_Estate



2481_A CE_BH01 28-Nov-17

0.2

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

0 0.000

0.5 0.478

1 0.905

1.5 1.087

2 1.236

2.5 1.421

3 1.575

4 1.859

5 2.086

6 2.304

7 2.548

8 2.781

9 2.988

10 3.134

12 3.586

15 4.278

20 5.273

25 6.215

30 6.405

40 9.077

50 12.479

1 60 16.312

70 20.247

80 24.189

1.5 90 28.138

100 31.967

110 35.596

2 120 38.969

130 42.046

140 44.719

2.5 150 47.727

160 51.624

Pump inlet

Constant Discharge Test (CDT 1) - Raw data

Test Duration: 3.25 hours

Absatraction rate (L/s)




2481_A CE_BH01 29-Nov-17

0.2


0 3.317

0.5 3.430

1 4.714

1.5 5.761

2 5.875

2.5 5.974

3 6.068

4 6.202

5 6.385

6 6.628

7 6.841

8 7.078

9 7.322

10 7.538

12 7.959

15 8.558

20 9.390

25 9.640

30 11.016

40 14.205

50 17.903

1 60 21.906

70 25.961

80 30.073

1.5 90 34.074

100 37.894

110 41.492

2 120 44.804

130 47.695

140 50.604

2.5 150 54.634

160 58.981

170 63.875

3 180 68.851

190 74.057

3.25 195 76.551

Pump inlet


Test Duration: 3.25 hours





2481_A CE_BH01 29-Nov-17


0 76.57

0.5 76.57

1 73.81

1.5 70.43

2 67.70

2.5 65.86

3 64.95

4 64.43

5 64.18

6 63.98

7 63.79

8 63.60

9 63.40

10 63.21

12 62.82

15 62.25

20 61.30

25 60.36

30 59.43

40 57.78

50 56.38

1 60 54.62

90 50.23

120 46.18

150 42.49

5 200 37.68

300 26.64

400 16.24

10 500 6.77

600 4.46

700 2.84

15 800 2.09

900 1.25

1000 0.80

20 1100 0.46

1200 0.16

1263 0.00

Post CDT Recovery




CE_BH02

Province

Area

Farm/Site Name

Observer Date Step no Length Comments

Pump type 22-Nov-17 1 1 hr 0.3 L/s Complete

34.04313 Lat 22-Nov-17 2 1 hr 0.8 L/s Complete

18.75118 Long 22-Nov-17 3 1 hr 1.5 L/s Complete

BoreholeStatus 22-Nov-17 4 1 hr 2.2 L/s Complete

Borehole depth (Before test) 19.13 m 22-Nov-17 5 55 mins 3.5 L/s Pump inlet

Borehole depth (After test) 19.13 m

Borehole diameter (OD,ID) 125 mm

Dummy pump test Complete

Casing depth PVC entire m Length (h) Comments

Casing height 0.41 m 10.1 2.0 l/s Pump inlet

Datum level above ground 0.65 m 14.47 1.5 l/s Pump inlet

Test pump depth 18.8 m

Observation pipe depth 15.8 m

Logger depth 15.78 m

Available Drawdown 13.28 m

3.15 mbch

2.5 mbgl

Outlet distance Borehole: Data:

Water sample taken & type CE_BH01 Hand

Rest water level before test

Somerset West

Croydon Estate

Co-ordinates

WILO QFN 25-25

Open

Maneul/Nunens

Test dateSite Details

Borehole Name CE_BH02

22-Nov-17 -Western Cape 25-Nov-17

Project Name Ian_de_Jager_Croydon_Estate

Project Number 2481_A

Borehole Yield Test Results

Step test details

Start Date

Flow rate (set)

Constant discharge test details

Flow rate (set)

23-Nov-17

23-Nov-17

Monitoring boreholes

Recovery details

Start Date Data Capture

Solinst logger24-Nov-17

Distance from: CE_BH02

717 meters

Comments:

Inorganic

100 m to neighboring dam




0.3 l/s 0.8 l/s


drawdown (m)Time interval (min)

Water level

drawdown (m)

0.5 0.095 60.5 0.494

1 0.839 61 0.610

1.5 0.811 61.5 0.663

2 0.534 62 0.702

2.5 0.468 62.5 0.731

3 0.395 63 0.751

4 0.339 64 0.804

5 0.324 65 0.820

6 0.330 66 0.862

7 0.297 67 0.885

8 0.308 68 0.921

9 0.317 69 0.938

10 0.294 70 0.953

12 0.303 72 0.993

15 0.299 75 1.020

20 0.326 80 1.034

25 0.351 85 1.108

30 0.374 90 1.108

40 0.390 100 1.182

50 0.409 110 1.233

60 0.423 120 1.337

1.5 l/s 2.2 l/s

120.5 1.429 180.5 2.833

121 1.623 181 3.069

121.5 1.693 181.5 3.197

122 1.771 182 3.271

122.5 1.811 182.5 3.344

123 1.842 183 3.381

124 1.901 184 3.494

125 1.963 185 3.565

126 2.006 186 3.627

127 2.050 187 3.676

128 2.087 188 3.722

129 2.119 189 3.762

130 2.145 190 3.816

132 2.202 192 3.881

135 2.257 195 3.976

140 2.333 200 4.100

145 2.400 205 4.193

150 2.464 210 4.270

160 2.565 220 4.435

170 2.652 230 4.556

180 2.741 240 4.667

Step 1 Step 2

22-Nov-17


Step 3 Step 4




3.5 l/s


drawdown (m)

240.5 4.678

241 4.8239

241.5 5.2767

242 5.5144

242.5 5.6668

243 5.7825

244 5.9854

245 6.135

246 6.2588

247 6.3702

248 6.4583

249 6.543

250 6.6127

252 6.7404

255 6.8977

260 7.0915

270 7.3723

280 7.5843

290 7.9819

300 12.4673

Pump inlet

Step 5


22-Nov-17



2481_A CE_BH02 22-Nov-17

2.0


0 1.459

0.5 2.358

1 2.614

1.5 2.689

2 2.793

2.5 2.913

3 2.965

4 3.115

5 3.232

6 3.332

7 3.414

8 3.493

9 3.569

10 3.629

12 3.729

15 3.875

20 4.053

25 4.166

30 4.283

40 4.472

50 4.629

1 60 4.743

70 4.881

80 4.986

90 5.075

100 5.172

2 120 5.340

150 5.567

200 5.895

250 6.177

5 300 6.424

350 6.674

400 6.886

450 7.095

500 7.177

550 7.490

10 600 12.136

10.1 606 12.800

Pump inlet


Test Duration: 10.1





2481_A CE_BH02 23-Nov-17

1.5


0 3.267

0.5 3.813

1 4.232

1.5 4.185

2 4.236

2.5 4.370

3 4.373

4 4.485

5 4.589

6 4.664

7 4.769

8 4.836

9 5.008

10 4.968

12 5.012

15 5.102

20 5.225

25 5.320

30 5.381

40 5.517

50 5.624

1 60 5.711

70 5.788

80 5.861

90 5.920

100 5.969

2 120 6.072

150 6.191

200 6.360

250 6.519

5 300 6.641

350 6.767

400 6.871

450 6.971

500 7.057

550 7.156

10 600 7.255

650 7.370

700 7.465

12.5 750 7.598

800 8.713

14.47 868 12.800

Pump inlet


Test Duration: 14.47





2481_A CE_BH02 24-Nov-17


0 12.80

0.5 9.37

1 7.86

1.5 7.54

2 7.34

2.5 7.21

3 7.09

4 6.87

5 6.76

6 6.64

7 6.55

8 6.45

9 6.36

10 6.27

12 6.12

15 5.94

20 5.71

25 5.56

30 5.44

40 5.26

50 5.10

1 60 4.97

70 4.84

80 4.74

2 120 4.45

150 4.27

200 4.03

250 3.82

5 300 3.63

400 3.32

500 2.97

12.5 750 2.42

1000 2.01

1250 1.68

25 1500 1.43

2000 1.05

2500 0.80

50 3000 0.61

3500 0.46

4000 0.36

75 4500 0.28

Post CDT Recovery




8. APPENDIX B: WATER QUALITY ANALYSIS



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